ALTERNATE FUELS FOR AUTOMOBILES BY M A QADEER

M A QADEER SIDDIQUI

ALTERNATE FUELS FOR AUTOMOBILES

BY

MD ABDUL QADEER SIDDIQUI [Bhaskar Engineering College, JNTU Hyderabad]

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M A QADEER SIDDIQUI

ALTERNATE FUELS FOR AUTOMOBILES

ALTERNATE FUELS FOR AUTOMOBILES

Md Abdul Qadeer Siddiqui B-Tech (Automobile Engineering) Bhaskar Engineering College (JNTU Hyderabad)

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ALTERNATE FUELS FOR AUTOMOBILES

Preface This book “Alternate fuels for automobiles” caters the need of JNTU-H specially. Each topic is explained in simple way to make student understand and comprehend the subject. Alternate fuel for automobiles is the study of various different fuels being used for automobiles. Various types of fuels other than petrol and diesel which are used in automobiles are discussed with their properties, advantages and limitations in details. Chapter 1 deals with the introduction to alternate fuels. The different types of fuels being used for automobiles, what are the benefits using these fuels are discussed. Chapter 2 deals with the CNG fuel in vehicles with its composition and properties and effect on vehicles. Chapter 3 is on LNG fuel in vehicles with its composition, properties and preparation. Chapter 4 deals with the LPG fuel in vehicles with its composition and properties and effect on vehicles. Chapter 5 deals with Liquefied hydrogen fuel. How it is produce, store and its efficiency with vehicle is discussed in brief. . Chapter 6 and chapter 7 focus on Bio fuels and electric vehicles. How the vehicle performance emissions differ with these fuels are discussed in these chapters. Chapter 8 gives a brief introduction to fuel cell power vehicles. The benefits of this fuel with different types of fuel cells are discussed here. The corrections, suggestions and feedbacks from the readers are always appreciated and duly acknowledged. You can reach the author at [email protected]

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Contents 1) OVERVIEW ………………..4 2) CNG(Compressed Natural Gas)………..21 3) LNG(liquefied Natural Gas)…………………47 4) LPG (Liquefied Petroleum Gas)………………….60 5) LIQUIFIED HYDROGEN……………………………….82 6) BIO FUEL………………………………………………………98 7) ELECTRIC VEHICLES……………………………………………..126 8) FUEL CELL VEHICLES………………………………………………….157

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CHAPTER 1 OVERVIEW INTRODUCTION Alternative fuels are derived from resources other than petroleum. Some are produced domestically, reducing our dependence on imported oil, and some are derived from renewable sources. Often, they produce less pollution than gasoline or diesel.

CLASSIFICATION OF ALTERNATE FUELS Natural Gas Natural Gas for use in automobiles is very popular in America because more than 80% of the natural gas used in U.S.A is produced in the country making it a lot cheaper than conventional petroleum. It is used either as Compressed Natural Gas (CNG) or Liquefied Natural Gas (LNG) when running motor vehicles. Moreover, it promises a reduction in smog of between 60 & 90% and a reduction of carbon emissions of between 30 & 40%. However, certain modifications need to be made on the cars and their tanks in order to use the fuel. Ethanol Ethanol is a biofuel used to run engines that originally used petrol. There are a few modifications done to the vehicle so that it can run efficiently on Ethanol. A vehicle with these modifications is classified as an FFV or a Flexible Fuel Vehicle. Brazil is one of the countries that have embraced this technology into their system becoming the second largest producer of ethanol in the world by producing sugarcane based ethanol .Through these developments, Brazil has been able to thrive in the Flex Fuel Vehicle market enabling them to manufacture cars like the Brazilian Fiat 147 [7], the first modern automobile that could run on pure-unblended ethanol followed by Volkswagens, Chevrolets, Toyotas and Nissans just to name a few .

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Biodiesel Like ethanol, biodiesel is a renewable alternative fuel for cars. This is because it is made from plants. Biodiesel does not require fermentation like ethanol; it is made by a process called trans-esterfication which converts vegetable fat into an oil that can be used to run ordinary diesel engines without any modifications necessary. Some vehicle manufacturers are wary of warranting their vehicles against the use of high blends of biodiesel above 5% [9] because there are concerns of the fuel’s impact on the engine. Biofuel from Watermelon & Plant Waste To counter the claims of environmentalists who are against the use of food crops for biofuel production and the use of arable land to grow energy crops rather than food crops , researchers have developed a biofuel from plant waste . It is estimated that about 20% of the watermelons produced in a farm cannot be sold for human consumption and go to waste; these can be converted into a biofuel because watermelon juice contains a considerable percentage of amino acids and directly fermentable sugars, which are essential for the production of bio-ethanol. Biofuel generated from plant wastes was used to power the limousines that transported certain heads of state to the Copenhagen Climate Summit in 2009. Alternative Fuel for Cars from Waste Chocolate A lot of research has gone into the improvement of biofuel production and application. One such study has led a firm in Preston called Ecotec to produce a biofuel from the waste collected during the processing of chocolate. The waste chocolate is turned into bio-ethanol then mixed with vegetable oil to run a special car they have branded the ‘Bio-Truck’.

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Propane/ Liquefied Petroleum Gas (LPG) LPG is made up of a mixture of hydrocarbon gases of which propane is in the largest percentage thus the fuel is often called Propane .LPG is produced from the processing of natural gas and the refining of petroleum. It can also be used domestically for cooking and boiling water. The propane is gaseous at room temperature but is liquefied when compressed to about 200 psi for storage in a special gas cylinder. The use of LPG to run automobiles is more popular in Europe that the US and makes up more than 10% of the motor fuel used in Netherlands. Hydrogen Hydrogen, as an alternative fuel for cars, is deployed either for use in Fuel Cell Vehicles (FCVs) or Internal Combustion Engines (ICEs). Hydrogen is considered the clean energy of the future burning in an internal combustion engine to produce heat and water vapor as well as other oxides of nitrogen which are also carbon neutral. In Fuel Cell Vehicles, Hydrogen is used in a totally different way; Hydrogen is stored on board and mixed with oxygen in the air to generate electricity via the fuel cell stack to power an electric motor that drives the vehicle. There are however, several challenges to overcome before hydrogen for automobiles can be used commercially. The Fuel Cell Vehicles as well as the Hydrogen Fuel is currently very expensive to produce and the technology of production is not widespread thus ordinary consumers cannot afford to use them. Furthermore, hydrogen contains less energy per unit volume compared to conventional automobile fuel; therefore, filling stations need to be established at high frequencies in the country of use before the technology can be commercially viable. Electricity Last but not least we have electricity. Electricity is the modern man’s fire and every technology is inclined to maximize the use of this energy source. The use of electricity as an alternative fuel has birthed vehicles of all shapes and sizes, from SUVs to Sports cars .The use of electricity has also led to the development of hybrid cars that run on fossil fuels and electricity alternatively –

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depending on the vehicle’s settings – such as the Toyota Prius and Honda Insight. However, like all mobile electric appliances, these vehicles contain batteries that need to be recharged. They have an advantage over hydrogen cars because they do not need several filling stations because electricity sources are widespread, but it is still a tedious time consuming process. The tesla motor company, which has specialized in the electric car production, has one of its best cars running for only 160 miles per charge .Electric cars are still not very popular because the automobile industry has not embraced the technology fully thus the cars are still rare. They do have several advantages over gasoline cars in that they do not produce any tail pipe emissions and cost about 2 US cents per mile compared to gasoline’s 12 US cents. Furthermore they do not require any of the services that a gasoline car needs such as oil changes and emission checks.

SCENERIO OF CONVECTIONAL FUELS The set of scenarios presented in this report describes a number of external developments, policy measures and manufacturer strategies that might influence the penetration of the various technological options. The baseline scenario is used as the reference case. It corresponds to the outlook for each technology if the current trends in demand are sustained, if fuel and vehicle prices and fuel economy follow the path predicted by current surveys of trends in vehicle technologies, and if no significant policy measure is implemented. According to the baseline scenario, no clear winner among the non-conventional technologies is identified. Fuel cells are expected to become an option only at the end of the 2010’s, while electric vehicles seem capable of securing a niche. Hybrids may play an interim role in the transition between ICEs to fuel cells. Total demand in the passenger car sector (expressed in total number of vehicle kms) is expected to rise (though slower than GDP growth). CO2 emissions from passenger cars are expected to show a slight increase by 2010 (3%) and a reduction of 13% by 2020. This is the combined result of the improvement of conventional technologies, the gradual removal of older cars from the fleet, and the introduction of alternative technologies.

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In the high oil scenario an increase of the price of oil is assumed. The increase is applied to the fuel prices predicted by the POLES model during the whole period of the simulation. As a reference, the price increase is considered to be equal to 28% (that would correspond to an increase from 25 to 32 US$ per barrel). Such an increase would have a minimal impact in the medium term (up to 2010), since the alternative technologies would not be mature enough (i.e. have competing costs) by then to benefit and increase their share. In the longer term, an increase in the price of oil would benefit the alternative technologies, since their difference from the conventional technologies in terms of variable cost would become smaller. As regards the conventional technologies, higher oil prices would reinforce the shift from gasoline to diesel, as fuel economy becomes a decisive factor. A higher oil price would also slow down growth in transport demand. The slower growth in demand, combined with the shift towards alternatives and more efficient vehicles, would also lead to further reductions in CO2 emissions. The high oil scenario is also equivalent to a fuel tax scenario, i.e. the same results would appear if fuel taxes were raised by 28%. The low oil scenario corresponds to the opposite case of the high oil scenario. A decrease of the price of oil by 28% is assumed (e.g. from 25 to 18 US$ per barrel). The results have in general the opposite direction of those for high oil: the introduction of alternative technologies is delayed and gasoline remains the most attractive option. Transport demand would increase, though still slower than GDP growth (saturation levels are reached). CO2 emissions would increase significantly by 2010 and in the long term brought down to the levels of 2000 as a result of improved technology. In the carbon tax 50 scenario, a carbon content related tax equivalent to 50 euros per ton of CO2 is imposed. The difference from the high oil price scenario (that also corresponds to imposing a fuel tax) is that it affects gasoline and diesel in a different manner. Diesel has a higher carbon content and is cheaper than gasoline. So while this carbon tax would mean an increase of gasoline prices by 12%, it would mean double the increase for diesel prices. As a result, although the results have the same direction as the results in the high oil scenario as regards the penetration of alternative technologies, they strongly favour gasoline as compared to diesel. Trends in Vehicle and Fuel Technologies Scenarios for Future Trends

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European Commission JRC-IPTS 12 the ESTO Network The carbon tax 100 scenario assumes a carbon content tax equivalent to 100 euros per ton of CO2. At that level of carbon tax the results would be comparable to that of the high oil price scenario, with the exception that gasoline has an advantage over both diesel and fuel cells. The other two alternative options, electric and –mainly hybrid- would also benefit. The three scenarios on subsidy for electric, hybrid and fuel cells correspond to a decrease of the purchase cost of each alternative technology by 2000 euros. This would decrease the price differential of these technologies compared to conventional technologies and accelerate their introduction. For electric, although its share is increased, this is not enough for the difference in costs to be covered. For hybrid and fuel cells, penetration is accelerated and each of the two can become an important technology by 2020. Subsidies would not have any significant impact on total transport demand, but would further marginally reduce CO2 emissions (except in the case of fuel cells). The zero emissions scenario assumes the prohibition of conventional technologies in urban areas. This would favour hybrid vehicles in the medium term and all alternative technologies, in a proportional way, in the longer term. The main losers would be the light gasoline (and in the longer term, the light diesel) cars, since their predominantly urban role would be played by alternative technologies. This scenario also leads to a reduction in CO2 emissions, though lower than in the case of high oil or carbon tax 100, where restrictions are applied to the whole fleet. In order to test the case of industry selecting winning technologies and concentrating solely on them, a number of scenarios where one or more of the alternative technologies is abandoned were investigated. The rationale behind those scenarios is that manufacturers will not be willing to concentrate on all five paths (2 conventional and 3 alternatives) but will instead concentrate only on a limited number (2 to 4). In all cases of concentrating in only 4 paths, the projected share of the technology that is abandoned is expected to be divided proportionally between the 4 paths. That is to say, none of the alternatives is in fact blocking the

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development of the other alternatives or the demand for them, although abandoning one of them could help establish the critical mass for either or both of them. In no electric, no significant impacts on the penetration of the other alternatives, since the projected share of electric was too small to make a difference. In no hybrid, conventional technologies would still monopolise the market in 2010, since no alternative options would be sufficiently attractive. By 2020, the lost projected share of hybrid would again be divided proportionally among the remaining options. No fuel cells, would have no impact until the end of the 2010’s. If fuel cells are the only alternative technology to be developed, the market will again be monopolised by conventional technologies until fuel cells improve significantly. But fuel cells will have then an important share of new registrations, higher than in baseline but still lower than in the high oil or subsidy fuel cells scenarios. But the situation in terms of CO2 emissions would be worse, since the hybrids that they would replace would emit less. The case of none of the alternative technologies being attractive enough (or manufacturers deciding to abandon all of them and concentrate on conventional technologies) is tested in no new scenario. Gasoline and diesel would share the market between them, and the main impact would be the worsening of the CO2 emissions outlook. Instead of being significantly reduced, emission levels would remain at year 2000 levels. The 2 variants of no new, are a combination with the oil price scenarios. If oil prices are high (no new, high oil), demand slows down and emissions demonstrate a small improvement. But in the case of low oil prices (no new, low oil), both transport demand and CO2 emissions increase dramatically.

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OIL RESERVES OF THE WORLD

List of Top 10 Oil Reserves Countries in the World Rank

Country

Oil Reserves (Billion Barrels)

% of World Total

1

Venezuela

297.6

18.2

2

Saudi Arabia

265.4

16.2

3

Canada

173.1

10.6

4

Iran

154.6

9.4

5

Iraq

141.4

8.6

6

Kuwait

101.5

6.2

7

UAE

97.8

6

8

Russia

80

4.9

9

Libya

48

2.9

10

Nigeria

37.2

2.3

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FUEL QUALITY ASPECTS RELATED TO EMISSION The automobile industry has to address the following issues at all the stages of vehicle manufacture: 

Environmental Imperatives



Safety Requirements



Competitive Pressures and



Customer Expectations

There is a strong interlinking amongst all these forces of change, influencing the automobile industry. These have to be addressed consistently and strategically to ensure competitiveness. Since pollution is caused by various sources, it requires an integrated, multidisciplinary approach. The different sources of pollution have to be addressed simultaneously in order to stall widespread damage. THE PARAMETERS DETERMINING EMISSION FROM VEHICLES 

Vehicular Technology



Fuel Quality



Inspection & Maintenance of In-Use Vehicles



Road and Traffic Management

While each one of the four factors mentioned above have direct environmental implications, the vehicle and fuel systems have to be addressed as a whole and jointly optimised in order to achieve significant reduction in emission. VEHICULAR TECHNOLOGY In India, the vehicle population is growing at rate of over 5% per annum and today the vehicle population is approximately 40 million. The vehicle mix is also unique to India in that there is a very high proportion of two wheelers (76%).

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History of Emission Norms in India The significant environmental implications of vehicles cannot be denied. The need to reduce vehicular pollution has led to emission control through regulations in conjunction with increasingly environment-friendly technologies. It was only in 1991 that the first stage emission norms came into force for petrol vehicles and in 1992 for diesel vehicles. From April 1995 mandatory fitment of catalytic converters in new petrol passenger cars sold in the four metros of Delhi, Calcutta, Mumbai and Chennai along with supply of Unleaded Petrol (ULP) was affected. Availability of ULP was further extended to 42 major cities and now it is available throughout the country. The emission reduction achieved from pre-89 levels is over 85% for petrol driven and 61% for diesel vehicles from 1991 levels. In the year 2000 passenger cars and commercial vehicles will be meeting Euro I equivalent India 2000 norms, while two wheelers will be meeting one of the tightest emission norms in the world. Euro II equivalent Bharat Stage II norms are in force from 2001 in 4 metros of Delhi, Mumbai, Chennai and Kolkata. Since India embarked on a formal emission control regime only in 1991, there is a gap in comparison with technologies available in the USA or Europe. Currently, we are behind Euro norms by few years, however, a beginning has been made, and emission norms are being aligned with Euro standards and vehicular technology is being accordingly upgraded. Vehicle manufactures are also working towards bridging the gap between Euro standards and Indian emission norms. FUEL TECHNOLOGY In India we are yet to address the vehicle and fuel system as a whole. It was in

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1996 that the Ministry of Environment and Forests formally notified fuel specifications. Maximum limits for critical ingredients like Benzene level in petrol have been specified only recently and a limit of 5% m/m and 3% m/m has been set for petrol in the country and metroes respectively. In place of phase-wise upgradation of fuel specifications there appears to be a region-wise introduction of fuels of particular specifications. The high levels of pollution have necessitated eliminating leaded petrol, through out the country. To address the high pollution in 4 metro cities 0.05% sulphur petrol & diesel has been introduced since 2000-2001. The benzene content has been further reduced to 1% in Delhi and Mumbai. There is a need for a holistic approach so that upgradation in engine technology can be optimised for maximum environmental benefits. Other factors influencing emission from vehicles. INSPECTION & MAINTENANCE (I&M) OF IN-USE VEHICLES It has been estimated that at any point of time, new vehicle comprise only 8% of the total vehicle population. In India currently only transport vehicles, that is, vehicles used for hire or reward are required to undergo periodic fitness certification. The large population of personalised vehicles are not yet covered by any such mandatory requirement. In most countries that have been able to control vehicular pollution to a substantial extent, Inspection & Maintenance of all categories of vehicles have been one of the chief tools used. Developing countries in the South East Asian region, which till a few years back had severe air pollution problem have introduced an I&M system and also effective traffic management. ROAD & TRAFFIC MANAGEMENT Inadequate and poor quality of road surface leads to increased Vehicle Operation Costs and also increased pollution. It has been estimated that

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improvements in roads will result in savings of about 15% of Vehicle Operation Costs. CONCLUSION The need for an integrated, holistic approach for controlling vehicular emission cannot be over-emphasised. More importantly, it is time now for the auto and oil industry to come together under the guidance of the Government in evolving fuel quality standards and vehicular technology to meet air quality targets. Petrol Vehicles Three - Wheelers (g/km) Year

CO

HC

HC+Nox

1991

12 - 30

8 - 12

-

-

1996

6.75

-

5.40

-

2000

4.00

-

2.00

-

2005(BS II)

2.25

-

2.00

(DF =1.2)

Two - Wheelers (g/km) Year

CO

HC

HC+Nox

1991

12 - 30

8 - 12

-

-

1996

4.50

-

3.60

-

2000

2.00

-

2.00

-

2005(BS II)

1.50

-

1.50

(DF =1.2)

Car (g/km) Year

CO

HC

Nox

HC+Nox

1991

14.3 - 27.1

2.0-2.9

1996

8.68 - 12.4

3.00 - 4.36

1998*

4.34 - 6.20

1.50 - 2.18

2000

2.78

0.97

B.S II

2.2

0.5

B.S II

2.2 - 5.0

0.5 - 0.7

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B.S III

2.30

0.2

0.15

B.S III

2.3 - 5.22

0.20 - 0.29

0.15 - 0.21

* For Catalytic Converter Fitted vehicles upto 6 seaters(A) & GVW upto 2.5 tons More than 6 seaters(B) & GVW upto 3.5 tons(A)(B) Diesel Vehicles Diesel Vehicles (GVM Upto 3.5 Tons) (g/km) Year

Engine Dynamometer CO

HC

Nox

HC+Nox

1992

14.0

3.5

18

1996

11.20

2.40

14.4

2000

4.5

1.1

8.0

PM

0.36/ 0.61 # For Four

B.S II

4.0

1.1

7.0

0.15 Wheelers only

Or (g/km) Year 1992 1996 2000

B.S II

Chassis Dynamometer CO 17.3 32.6

HC

Nox

HC+Nox

PM Light Duty

2.7 - 3.7

Vehicles

5.0 - 9.0

2.0 - 4.0

2.72 -

0.97 -

0.14 -

6.90

1.70

0.25

1.0 - 1.5

0.7 - 1.2

0.08 0.17

For Four Wheelers only For 2 & 3

B.S II(2005)

1.00

0.85

0.10

Wheelers, Appropriate DF

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B.S III

ALTERNATE FUELS FOR AUTOMOBILES

0.64 -

0.50 -

0.56 -

0.05 -

0.95

0.78

0.86

0.10

Cars (g/km)

Chassis Dynamometer

B.S II

1.0

0.7

B.S II

1.0 - 1.5

0.7 - 1.2

B.S III

0.64

0.50

0.56

0.05

0.64 -

0.50 -

0.56 -

0.05 -

0.95

0.78

0.86

0.10

B.S III

0.8 0.8 0.17

(A) (B) (A) (B)

Diesel Vehicles (GVM > 3.5 Tons) (g/kwh) Year

CO

HC

Nox

HC+Nox

PM$

1992

14.0

3.5

18

1996

11.20

2.40

14.4

2000

4.5

1.1

8.0

B.S II

4.0

1.1

7.0

0.15

B.S III

2.1

0.7

5.0

0.10/0.13

Smoke (m-1) $

0.36/ 0.36 # 0.8

NEED FOR ALTERTNATIVE FUEL 1. Fossil fuels are in limited supply. 2. Global consumption of fossil fuels is increasing, and much of that increase is from the transportation sector. 3. While automobile fuel efficiency has improved over the last 30 years, improvements have been fairly level since the mid 1980’s. Efforts to improve fuel efficiency are limited by the increased use of heavy vehicles such as sport utility vehicles and light trucks for personal use. 4. Fossil fuel combustion releases large amounts of greenhouse gases, the most significant being carbon dioxide. 5. Greenhouse gases trap heat in the earth’s atmosphere.

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6. In a greenhouse, visible sunlight easily penetrates glass or plastic walls, but heat (in the form of infrared radiation) does not escape. 7. Most scientists concur that the average temperature of the Earth is increasing, and if human activity is the principal cause. 8. Increased concentrations of carbon dioxide in the atmosphere contribute to global warming, which is receiving world-wide attention as a significant environmental problem. 9. Individuals can have a positive impact on the environment by making appropriate choices in our daily lives – mostly with respect to transportation, home energy use, and waste disposal. Also Gasoline and diesel have been our primary fuels used in automotive, farm and recreational vehicles for decades. Our dependence on other countries to provide us with gasoline has gone into a downward spiral with the economy doing so poorly and the poor mileage rated cars that are being produced. Without having a certain level of efficiency in our vehicles, we are only pushing ourselves closer to the point of necessitating an alternate fuel source. Oil production is expected to diminish to a near halt as near as forty years from now. It’s time to start really digging in and getting other renewable energy sources into mainstream use. Many automakers pride themselves in their high performance vehicles, and the world has been brain washed into thing that bigger and faster is almost always better. We need to start thinking smarter before it’s too late.

REGULATORY FRAMEWORK FOR CNG/LPG VEHICLES IN INDIA

1. Petrol/CNG/LPG Driven Vehicles Measured at idling: Vehicle Type

CO

*HC

(%) (ppm)

2&3 wheelers (2/4 stroke) (vehicles manufactured 4.5

9,000

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before 31/3/2000) 2&3 wheelers (2- stroke) (vehicles manufactured after

3.5

6,000

3.5

4,500

Bharat Stage -II compliant 4 wheelers

0.5

750

Four wheelers other than Bharat Stage -II compliant

3.0

1,500

31/3/2000) 2&3 wheelers (4 stroke) (vehicles manufactured after 31/3/2000)

* For CNG & LPG vehicles the measured Hydrocarbon value shall be converted using the following formula and

then

compared

with

the

limits

· For CNG Vehicles- Non Methane Hydrocarbon, NMHC

=

0.3

X

HC

· For LPG Vehicles- Reactive Hydrocarbon, RHC = 0.5 X HC 2. Diesel Vehicles Free Acceleration Smoke Test Method of Test

Maximum Smoke Density Light

Absorption Hartidge Units

Coefficient (1/m) Free Acceleration Test for Turbo Charged

engine

and

Naturally 2.45

65

aspirated engine Notes: 1.

Test

should

be

done

at

Authorised

Pollution

Check

Centers

2. Test should be done every six months or as per State Government's direction 3. No vehicle shall ply in the country without a valid pollution under control certificate

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Looking Into the Future With the continually rising cost of gasoline it has never been more important to explore alternatives in getting us from one place to another. We have some really great options available to us today that have shortcomings that should be simple to overcome. For instance, if each filling station would install one single EV charging station or any of the other above listed methods, they would all become viable solutions. My personal favorite at the moment is electric, because the conversion is so simple and emmission free at the vehicle level. Once we can create clean electricity via wind farms, water turbines, solar farms etc... I think that this option with really take off. My second favorite in this list is Biodeisel. While I'm not a huge fan of deisel engines, I do quite fancy the idea of being able to run my vehicle on recycled fryer grease. No matter how you look at it or which option is your personal favorite, it's good to keep an open mind, because someday, gasoline may no longer be a viable option.

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CHAPTER 2 COMPRESSED NATURAL GAS (CNG) Safe for transportation? Yes, natural gas vehicles or NGVs, must meet the strictest of safety standards. The vehicles, fuel systems, conversion companies, and tank manufacturers must each meet separate government regulated guidelines and codes to sell in the market place. Compared to gasoline The fuel itself is safer than traditional gasoline in many ways. 1) Natural gas is lighter than air. This means, in the case of accident and gas is released, natural gas will disperse into the atmosphere, where gasoline will collect and spread on the ground. 2) Natural gas has a higher ignition temperature than gasoline, which means it takes higher temperatures to start a flame. 3) Last the tanks must withstand extreme tests against dynamite, gunfire, bonfires and others that would destroy a normal gasoline tank. More Safety To learn more specifically about regulations and safety guides, visit Department of Transportation or check out our links pages for others sources. Availability Natural gas is drilled from wells or extracted from crude oil production. This fuel powers about one quarter of the United States energy usage, of that less than one percent goes toward transportation. America has also set up a vast natural gas distribution system that stretches coast to coast and boarder to boarder. This system delivers gas economically and quickly to almost all 48 states in the continental US. Sources have indicated that America owns roughly 2,074 Tcf (trillion cubic feet) of natural gas, which is more than a 100 year supply. There are about 12,000 fueling stations across global roads, but only about 1,100 on U.S. roadways. However many initiatives are in place to expand infrastructure, such

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as the Triangle, Atlanta and the existing infrastructure established in the West, demonstrates that infrastructure is on the rise and so is demand. American Eighty to ninety percent of the natural gas used in the U.S. is found here in America. This helps promote America’s energy independence from the reliance on foreign fuels. Only 3 percent of US natural gas consumption comes from sources other than America, compared to oil imports. The US imports more than 50 percent of its oil from foreign oil, greatly hindering America’s energy independence. Affordable CNG is much cheaper than gasoline or diesel, in most cases half as much, in others as much as 80 percent less, depending on the station and state. Natural gas costs range from 20-40 percent less than crude oil on an energy-equivalent basis. Fleet owners will experience the greatest savings. A May 2012 Wall Street Journal article stated that Waste Management will convert trucks over the next five years to natural gas at a cost of $30,000 per truck. These vehicles will save $27,000 each year in fuel costs compared to diesel. Greener Natural gas produces far less emissions than engines running on petroleum based fuels. NGVs emits 25 percent less CO2 than vehicles that run on traditional gasoline or diesel. Natural gas is also available in renewable forms such as methane from landfills, stranded gas wells, agricultural operations, and new emerging methods that can be converted to clean natural gas. NGVs also make it much easier to meet stringent EPA standards. Other benefits Easy fill-up- Just as fast and easy as gasoline or diesel Government support- Federal & state incentives Extended vehicle life by up to 50,000 miles Reduced maintenance

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HISTORY OF CNG Natural gas was first used as a transportation fuel in Italy in the 1930s after World War II. There are more than 14.8 million vehicles on global roads today. Most located internationally in countries such as Iran, Pakistan and Argentina; these three countries make up the largest users of natural gas vehicles (NGVs). The U.S. has been slow to join the alternative fuel vehicle (AFV) market. Unfortunately, less than 120,000 vehicles are running on natural gas in the U.S. The average global growth rate is about 30 percent since 2000; however America’s NGV growth rate is only about 3.7 percent per year. Over the past forty years, natural gas has increased in pressure four times, from 2,000 pounds per square inch (psi) to 2,400; 3,000; and most recently 3,600 psi. These increases of pressure, have advanced tanks to hold more and more fuel in smaller and smaller spaces. These advanced pressures were accomplished by new technologies in tank designs. Todays tanks have advanced into four main categories:

How is CNG produced?

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Once a potential natural gas deposit has been located by a team of exploration geologists and geophysicists, it is up to a team of drilling experts to dig down to where the natural gas is thought to exist. Although the process of digging deep into the Earth’s crust to find deposits of natural gas that may or may not actually exist seems daunting, the industry has developed a number of innovations and techniques that both decrease the cost and increase the efficiency of drilling for natural gas. Advancements in technology have contributed greatly to the increased efficiency and success rate for drilling natural gas wells. Within the last decade new technology in horizontal drilling has enabled experts to access deeper shale plays of natural gas as well as to drill horizontally in all directions to enable one well to reach a much larger reserve of natural gas than traditional shallow wells were are able to do. Determining whether to drill a well depends on a variety of factors, including the economic potential of the hoped-for natural gas reservoir. It costs a great deal of money for exploration and production companies to search and drill for natural gas, and there is always the inherent risk that no natural gas will be found. The exact placement of the drill site depends on many factors, including the nature of the potential formation to be drilled, the characteristics of the subsurface geology, and the depth and size of the target deposit. After the geophysical team identifies the optimal location for a well, it is necessary for the drilling company to ensure that it completes all the necessary steps so that it can legally drill in that area. This usually involves securing permits for the drilling operations, establishment of a legal arrangement to allow the natural gas company to extract and sell the resources under a given area of land, and a design for gathering lines that will connect the well to the pipeline. If the new well, once drilled, does in fact come in contact with natural gas deposits, it is developed to allow for the extraction of this natural gas, and is termed a ‘development’ or ‘productive’ well. At this point, with the well drilled and hydrocarbons present, the well may be completed to facilitate its production of natural gas. However, if the exploration team was incorrect in its estimation of the

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existence of a marketable quantity of natural gas at a wellsite, the well is termed a ‘dry well’, and production does not proceed. Onshore and offshore drilling present unique drilling environments, requiring special techniques and equipment. The first diagram depicts both the horizontal drilling and traditional shallow drilling techniques to access the deeper shale plays and the shallow sandstone plays, respectively. The second diagram depicts various types of offshore drilling setups.

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CNG Properties CNG in general CNG is a natural product. It evolved from organics matters over 600 Million years ago. Today it is drawn from domestically drilled gas wells or in conjunction with crude oil production. CNG is used in its primary gasiform state. Since it does not have to be transformed into any secondary energy such as fuel oil or electricity, the user can utilize it right away and in addition no environmental pollution through any complex transformation occurs. Stocking, ordering or delivery dates are not necessary in connection with CNG. Chemical Composition Natural gas consists of about 90% methane. In its natural form natural gas does not smell. Therefore, the gas is odorized prior to distribution in order to detect possible leakage. Gas can therefore be smelled already at a concentration of 0.3%. As CNG requires a concentration of about 5% to 15% to combust, 0.3% is far below the dangerous combustion level. Physical attributes of CNG If the cylinder is depleted and refilled with CNG, the cylinder will get warm. This is nothing to be concerned about. If a gas is put under pressure, the density of the molecules will increase, and therefore the temperature will rise. After a while it will adopt the temperature of its environment again. Contrariwise the cylinder cools down while driving. When gas expands the density of the molecules decreases and the temperature drops; a nice side-effect in a warm climate like Singapore. These physical attributes also have an effect on the total storage capacity of the cylinder when refueling. If the temperature increases, the pressure in the cylinder increases as well. The dispensers at the filling stations automatically stop dispensing CNG, once a pressure of 200 bar is reached. If a cylinder can theoretically accommodate 18 kg CNG under standard conditions (200 bar pressure, 15° Celsius), the cylinder will carry a bit less than 18 kg. Practically this means that the

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cooler the cylinder and the temperature around the cylinder is the more kg of CNG can be pumped into the cylinder. A CNG car can be left in the sun without concerns, as this heat is never sufficient enough to heat up the cylinder to a critical point. The cylinders are tested and can sustain a pressure of up to 500 bar - a pressure dimension, which is usually never reached in our daily environment. CNG measured in Kg CNG is measured in the mass unit kg and not in liters or m³, both measures for volume. One cubic meter of CNG under 10 bar pressure has just a fraction of the energy value than one cubic meter of CNG under 200 bar pressure. However, one kilogram of CNG has always the same calorific value, no matter whether it has a volume of 500 liters, or just a volume of 60 liters - under 200 bar pressure. 1 kg CNG = 1.51 liters of Petrol

How is CNG Stored? As mentioned, natural gas is highly pressurized as it travels through an interstate pipeline. To ensure that the natural gas flowing through any one pipeline remains pressurized, compression of this natural gas is required periodically along the pipe. This is accomplished by compressor stations, usually placed at 40 to 100 mile intervals along the pipeline. The natural gas enters the compressor station, where it is compressed by either a turbine, motor, or engine. Turbine compressors gain their energy by using up a small proportion of the natural gas that they compress. The turbine itself serves to operate a centrifugal compressor, which contains a type of fan that compresses and pumps the natural gas through the pipeline. Some compressor stations are operated by using an electric motor to turn the same type of centrifugal compressor. This type of compression does not require the use of any of the natural gas from the pipe; however it does require a reliable source of electricity nearby. Reciprocating natural gas engines are also used to power some compressor stations. These engines resemble a very large automobile engine, and are powered

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by natural gas from the pipeline. The combustion of the natural gas powers pistons on the outside of the engine, which serves to compress the natural gas. In addition to compressing natural gas, compressor stations also usually contain some type of liquid separator, much like the ones used to dehydrate natural gas during its processing. Usually, these separators consist of scrubbers and filters that capture any liquids or other unwanted particles from the natural gas in the pipeline. Although natural gas in pipelines is considered ‘dry’ gas, it is not uncommon for a certain amount of water and hydrocarbons to condense out of the gas stream while in transit. The liquid separators at compressor stations ensure that the natural gas in the pipeline is as pure as possible, and usually filter the gas prior to compression. Natural gas, like most other commodities, can be stored for an indefinite period of time. The exploration, production, and transportation of natural gas takes time, and the natural gas that reaches its destination is not always needed right away, so it is injected into underground storage facilities. These storage facilities can be located near market centers that do not have a ready supply of locally produced natural gas. Traditionally, natural gas has been a seasonal fuel. That is, demand for natural gas is usually higher during the winter, partly because it is used for heat in residential and commercial settings. Stored natural gas plays a vital role in ensuring that any excess supply delivered during the summer months is available to meet the increased demand of the winter months. However, with the recent trend towards natural gas fired electric generation, demand for natural gas during the summer months is now increasing (due to the demand for electricity to power air conditioners and the like). Natural gas in storage also serves as insurance against any unforeseen accidents, natural disasters, or other occurrences that may affect the production or delivery of natural gas. Natural gas storage plays a vital role in maintaining the reliability of supply needed to meet the demands of consumers.

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ADVANTAGES AND DISADVANTAGES OF CNG ADVANTAGES OF CNG: a) Affordable Price One of the biggest advantages CNG it that it provides is an affordable energy source. As the world continues to experience high costs of gasoline, the low price of CNG offers a glimmer of hope. A classic example, would be in the case of where a consumer uses natural gas vehicle (NGV) that is powered by CNG for about 50 km daily in the west of America. This car owner is actually able to save more than $600 per year by taking advantage of the 85¢ gallon per gasoline equivalent compared to his counterparts who use gasoline for $4.33. CNG is typically, at least, 30% cheaper than gasoline. b)*Fuel*economy Not only is CNG cheaper, it also gives consumers fuel efficiency. Considering the price of gasoline in India, which costs 50 Rs/liter (even though being largely government subsidized), in comparison to CNG that sells for only 22 Rs. While expensive petrol gives a standard car owner about 15 km per liter, the low-cost CNG offers close to 20 km . A CNG full cylinder promises more than 300 km of driving range. Many fueling stations sell both CNG and gasoline available for purchase, and the choice is therefore placed in the hands of automobile owners. As far as fuel saving is concerned, it is clear that CNG is giving consumers the upper hand. c)*Reduced*up*keeping*cost! Besides, CNG becoming a vehicle owner’s best friend as it offers the potential of preserving the well being of the vehicle, which translates into reduced up keeping cost. CNG is non-corrosive in nature, and is free from lead-like substances that are widely used as additives in gasoline. This makes it possible to prevent spark plugs from lead poisoning. In addition to that, it must be noted that CNG fuel system is designed to keep the gas lock in, thus eliminating its probabilities of dispersing into the air, or spilling. CNG is also known to preserve the life of oils and lubricating oils and has been known to last longer due to the non-contaminating quality of natural gas. CNG, which scores low on flammability, contrasted by a high auto ignition temperature, it is not likely to cause a fire, considering that it is lighter than air.

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d)*Environmentally*Friendly! Apart from that, the clean attributes of CNG gives it reasons to be applauded by nature conservationists for being environmentally friendly. As a concerted effort is being taken across the globe to save the earth, CNG is way better that petrol, as it emits less harmful gases such as carbon dioxide, carbon monoxide, hydrocarbons, nitrogen oxides and sulfur oxides into the air releases less carbon dioxide by almost 6000 grams, compared to a gasoline-powered engine. It’s colorless and odorless traits make it a clear burning fuel that prevents black fumes when burnt. The use of CNG is definitely a forward move; lessening the emission of greenhouse gases that pose the risk of global warming. e) Abundant*Supply! Another big plus point about CNG is in abundant supply as it is widely available throughout the world. According to official energy statistics from the U.S government, Middle East accounts for the largest increase in regional natural gas production from 2006 to 2030, and is projected to contribute to more than one-fifth of the total increment in world natural gas production. Following this Europe and Eurasia will produce the second highest amount of CNG. Nigeria also shows great potential for natural gas productions. As of now, Russia holds the world’s largest reserve of natural gas, followed by Iran. North America also produces CNG in enormous volumes, storing up reserves that are enough for the next hundred and twenty years, according to a study by Navigant Consulting, Inc. The daily production of natural gas from shale formation in 1998 was a bare billion cubic feet per day. Now, the number has increased tremendously to 5 billion cubic feet per day, creating a compounding yearly growth rate of more than 20%. This is more than 30 times the rate for that period of time. Asia is also not left behind, with China exhibiting the highest CNG production. f) Lower*Dependency*on*Foreign*Fuel*Imports! As observed, natural gas production is increasing in different countries across the globe. This brings about another advantage for countries to experience lower dependency on foreign fuel imports. Over the years, the Middle East has been monopolizing the supply of petroleum and oil prices predicted to continue to soar. This had made countries like the United States fuel dependent, which led the former

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President, President Bush to say that the U.S was “addicted to oil”. President Obama is aiming towards zero oil imports into the United States. The world is turning towards natural gas as a substitute. According to the International Energy Outlook 2009 by the Energy Information Administration of USA, an average of 1.6 percent of yearly increase is expected for the total consumption of natural gas, globally. This means that in 2030, 153 trillion cubic feet of natural gas consumption is projected, from a total of 104 trillion cubic feet in 2006. Considering this, the US has reason to be pleased that North America is a self-contained market of natural gas, and the continuous increase of its supply will ultimately help make the country independent on fuel imports. Given the benefits of CNG, natural gas offers significant development and progress on the countries’ economy besides, being kinder to consumers and also the environment. Needless to say, CNG is much more promising than petroleum based fuel. Considering its advantages, further research and studies are being conducted to bring natural gas to greater heights and make it accessible for greater use as the alternative energy of the future. DISADVANTAGES OF CNG a) The*Lack*of*Fueling*Stations*Within*Regions* There are close to 120,000 natural gas vehicles in the United States and around 150,000 NGVs being used on the road; the most of them consisting of trucks. Altogether, there are about 10 million natural gas powered vehicles in the world. To cater for this need, it is estimated that there are only about 1,500 natural gas fueling stations on a national scale in the US. Only about half of these stations are open to the public. In contrast, there are more than 190,000 gasoline stations in the US. Many vehicle owners are reluctant to switch to CNG because of the difficulty they face refueling. For example, they might drive to locations that are not equipped with CNG stations. Car users find it more convenient to utilize petrol as their source of fuel as it is easily accessible everywhere. This shortfall in fueling infrastructures has led to many consumers to turn down CNG as their main fuel for their vehicles. If the use of CNG increases, it is still questionable whether the infrastructure can be developed at a matching pace worldwide, considering the cost to be incurred.

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b) Vehicle*Owners*Attitude* Besides the fact that fuel stations are rather limited, vehicle owners have doubts about the usage of CNG for their vehicles. This is because CNG vehicles presently own a lesser range compared to gasoline powered vehicles. An energy gallon equivalent of natural gas, whether compressed natural gas or liquid natural gas, contains less energy, if measured up against a volumetric gallon of petrol or diesel fuel. It is said that compressed natural gas needs to be keep at an extremely high pressure, close to 4,000 pounds per square inch, to attain satisfactory driving range. Attempts have been made by liquefied natural gas to rectify this problem but it requires special storage equipment. This is very problematic and will also bring about additional costs. Considering this, vehicles running on natural gas are not as good traveling long distances. The lesser driving range offered by CNG powered vehicles once again cause consumers to prefer cars using gasoline. c) Additional*Equipment*Have*to*be*installed* It must also be noted that vehicles operating on CNG cost more than vehicles running on gasoline. This is because natural gas vehicles have to be installed with additional components for the storage of fuel, which are more costly than gasoline tanks. For example, the Honda Civic Sedan that consumes gasoline costs around $22,255 in the United States. CNG DISPESING SYSTEMS CNG Dispensers – Fueling the Greens

Maximize your fueling options; minimize your costs. Gilbarco’s Encore CNG dispenser makes it easy to bring Compressed Natural Gas to your forecourt. Integration into your existing POS and the familiar Encore user interface increase throughput and enhance your customers experience. Seamless integration. The familiar Encore frame and door construction allows integration into your forecourt with trusted Encore dispensers. The Encore CNG dispenser also ties to your existing

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forecourt controller, minimizing impact to your site payment network and saving you the cost of a separate POS system. Familiar user interface The intuitive Encore user interface enhances the customer experience while shortening their wait time. Encore S and Encore 700 S models provide consistent options and payment features. Fast, safe and efficient fill. The new Sequence Control increases fill rate, improving throughput. External and manual shut off valves allow for continuous flow of gas to the vehicle until stopped by the electronic flow control system or stopped manually. And with the carbon sensor in lieu of a cabinet purge system, you minimize your operational cost while maintaining a safe fueling environment. Flexibility at the pump Now you can have one dispenser for hi and standard flow applications, giving you the flexibility to fill cars or busses from the same dispenser.

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Compressed natural gas (CNG) is a highly pressurized fossil fuel that acts as an alternative to gasoline, diesel and LPG. Popularly known as the green fuel because of its environment friendly characteristics and being extremely cost effective in comparison to gasoline and diesel, CNG is quickly turning into the most preferred alternative fuel around the world. And in line with Gilbarco’s commitment to offer its customers superior and futureready equipment, the Encore series is a one-of-its kind unit that offers the broadest set of flexible fuel options. The re-designed Encore retains all its primary features and comes with added environment friendly alternatives. Fully equipped to dispense up to six different fuel types namely unleaded gasoline, diesel, CNG, biodiesel, E85, and LPG, the Encore dispenser line helps dispense a variety of environment friendly fuels from a single fueling position. Additionally, the single fuel position also helps keep the number of tanks needed to a minimum thereby optimizing the site’s efficiency. The Encore series is well known in the industry for its low-maintenance and highreturn-on-investment proposition and the added capability to dispense environment friendly fuel is the ideal way for you to associate your enterprise with the green initiative and maximize your branding and sales opportunities. And all this comes to you with the unmatched durability and reliability you have come to expect from the industry leader in flexible fuel. CNG Transportation The efficient and effective movement of natural gas from producing regions to consumption regions requires an extensive and elaborate transportation system. In many instances, natural gas produced from a particular well will have to travel a great distance to reach its point of use. The transportation system for natural gas consists of a complex network of pipelines, designed to quickly and efficiently transport natural gas from its origin, to areas of high natural gas demand. Transportation of natural gas is closely linked to its storage: should the natural gas being transported not be immediately required, it can be put into storage facilities for when it is needed.

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There are three major types of pipelines along the transportation route: the gathering system, the interstate pipeline system, and the distribution system. The gathering system consists of low pressure, small diameter pipelines that transport raw natural gas from the wellhead to the processing plant. The United States has an extensive transportation and storage system in place, as we have been using natural gas as a heating and electrical source of energy for quite some time. The good news is that these same pipelines can be utilized to help the United States achieve transportation energy independence by transporting natural gas to be used as vehicular fuel as well. CNG FUEL KIT

1) CNG is fed into the high pressure cylinders through the natural gas receptacle 2) When the engine needs natural gas, CNG leaves the storage cylinders and passes through the master manual shut-off valve. 3) CNG enters the engine chamber via the stainless steel high pressure line.

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4) The regulator accepts the CNG and reduces its pressure from 3,000 psi to approximate atmospheric pressure. 5) The natural gas solenoid valve lets the natural gas flow from the regulator into the gas mixer or fuel injectors. This same solenoid valve also shuts off the natural gas when the engine is stopped. 6) CNG mixes with air and flows down through the carburettor or fuel injection system and enters the engine’s combustion chambers.

Layout of CNG kit in a vehicle MATERIAL COMPATIBILITY FOR CNG 

Stainless steel



Aluminium



Copper



Elastomers

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Chapter 3 LNG (Liquefied Natural Gas) INTRODUCTION Natural gas is a major source of energy, but many towns and cities that need the energy are located far from the gas fields. Transporting gas by pipeline can be costly and impractical. We create LNG by cooling the gas to a liquid to -160ºC, which we can then ship out, safely and efficiently. LNG is a clear, colourless, non-toxic liquid that can be transported and stored more easily than natural gas because it occupies up to 600 times less space. When LNG reaches its destination, it is returned to a gas at regasification facilities. It is then piped to homes, businesses and industries. Shell helped pioneer the LNG sector, providing the technology for the world's first commercial liquefaction plant at Arzew, Algeria, in 1964. Since then, we have continued to improve the technology behind LNG.

HISTORY OF LNG Natural gas liquefaction dates back to the 19th century when British chemist and physicist Michael Faraday experimented with liquefying different types of gases, including natural gas. German engineer Karl Von Linde built the first practical compressor refrigeration machine in Munich in 1873. The first LNG plant was built in West Virginia in 1912 and began operation in 1917. The first commercial liquefaction plant was built in Cleveland, Ohio, in 1941.17 The LNG was stored in tanks at atmospheric pressure. The liquefaction of natural gas raised the possibility of its transportation to distant destinations. In January 1959, the world's first LNG tanker, The Methane Pioneer, a converted World War ll liberty freighter containing five, 7,000 barrel equivalent aluminum prismatic tanks with balsa wood supports and insulation of plywood and urethane, carried an LNG cargo from Lake Charles, Louisiana to Canvey Island, United Kingdom. This event demonstrated that large quantities of liquefied natural gas could be transported safely across the ocean.

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Figure 3. British Gas Canvey Island LNG Terminal, A World First Over the next 14 months, seven additional cargoes were delivered with only minor problems. Following the successful performance of The Methane Pioneer, the British Gas Council proceeded with plans to implement a commercial project to import LNG from Venezuela to Canvey Island. However, before the commercial agreements could be finalized, large quantities of natural gas were discovered in Libya and in the gigantic Hassi R' Mel field in Algeria, which are only half the distance to England as Venezuela. With the start-up of the 260 million cubic feet per day (MMcfd) Arzew GL4Z or Camel plant in 1964, the United Kingdom became the world's first LNG importer and Algeria the first LNG exporter. Algeria has since become a major world supplier of natural gas as LNG. After the concept was shown to work in the United Kingdom, additional liquefaction plants and import terminals were constructed in both the Atlantic and Pacific regions. Four marine terminals were built in the United States between 1971 and 1980. They are in Lake Charles (operated by CMS Energy), Everett, Massachusetts (operated by SUEZ through their Distrigas subsidiary), Elba Island, Georgia (operated by El Paso Energy), and Cove Point, Maryland (operated by Dominion Energy). After reaching a peak receipt volume of 253 BCF (billion cubic feet) in 1979, which represented 1.3 percent of U.S. gas demand, LNG imports declined because a gas surplus developed in North America and price disputes occurred with Algeria, the sole LNG provider to the U.S. at that time. The Elba Island and Cove Point receiving

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terminals were subsequently mothballed in 1980 and the Lake Charles and the Everett terminals suffered from very low utilization. The first exports of LNG from the U.S. to Asia occurred in 1969 when Alaskan LNG was sent to Japan. Alaskan LNG is derived from natural gas that is produced by ConocoPhillips and Marathon from fields in Cook Inlet in the southern portion of the state of Alaska, liquefied at the Kenai Peninsula LNG plant (one of the oldest, continuously operated LNG plants in the world) and shipped to Japan. The LNG market in both Europe and Asia continued to grow rapidly from that point on. The figure below shows worldwide growth in LNG since 1970.

PROPERTIES OF LNG Liquified Natural Gas (Liquid Methane) is made by cooling natural gas to a temperature of -260°F. At that temperature, natural gas becomes a liquid and its volume is reduced 615 times. (A car reduced 615 times would fit on your thumbnail.) Liquified natural gas is easier to store than the gaseous form since it takes up much less space. LNG is also easier to transport. People can put LNG in special tanks and transport it on trucks or ships. Today more than 100 LNG storage facilities are operating in the United States. Methane is a colorless, odorless gas with a wide distribution in nature. It is the principal component of natural gas, a mixture containing about 75% CH4, 15% ethane (C2H6), and 5% other hydrocarbons, such as propane (C3H8) and butane (C4H10). The "firedamp" of coal mines is chiefly methane. Anaerobic bacterial decomposition of plant and animal matter, such as occurs under water, produces marsh gas, which is also methane. At room temperature, methane is a gas less dense than air. It melts at -183°C and boils at -164°C. It is not very soluble in water. Methane is combustible, and mixtures of about 5 to 15 percent in air are explosive. Methane is not toxic when inhaled, but it can produce suffocation by reducing the concentration of oxygen inhaled.

A trace amount of smelly organic sulfur compounds (tertiary-butyl

mercaptan, (CH3)3CSH and dimethyl sulfide, (CH3)2S) is added to give commercial

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natural gas a detectable odor. This is done to make gas leaks readily detectible. An undetected gas leak could result in an explosion or asphyxiation. Methane is synthesized commercially by the distillation of bituminous coal and by heating a mixture of carbon and hydrogen. It can be produced in the laboratory by heating sodium acetate (CH3COONa) with sodium hydroxide (NaOH) and by the reaction of aluminum carbide (Al4C3) with water. In the chemical industry, methane is a raw material for the manufacture of methanol (CH3OH), formaldehyde (CH2O), nitromethane (CH3NO2), chloroform (CH3Cl), carbon tetrachloride (CCl4), and some freons (compounds containing carbon and fluorine, and perhaps chlorine and hydrogen). The reactions of methane with chlorine and fluorine are triggered by light. When exposed to bright visible light, mixtures of methane with chlorine or fluorine react explosively. The principal use of methane is as a fuel.

Property

Value

Symbol

LNG

Melting Point

54.36 K

Boiling Point

111.6 K

Heat of Vaporization (@101.325 kPa)

212.9 kj/kg K

Specific Heat (Cp, 0°C @ 101.325 kPa)

1.70 kj/kg K

Viscosity

188.0 kg/m-s X 106

Thermal Conductivity (k)

151.4 mW/m-k

Critical Temperature

154.576 K

Critical Pressure

5.04 MPa

Temperature at Triple Point

54.35 K @ 151 Mpa

Saturated Liquid Density (p) @ 0°C, 101.325 kPa

442.6 kg/m3

Phase at Room Temperature (20°C)

Gas

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THE ADVANTAGES OF LIQUEFIED NATURAL GAS Liquefied natural gas (LNG) boasts a number of advantages, which are driving its growth. It combines the clean combustion and calorific value of natural gas with the transportation flexibility of liquid hydrocarbons. Gas, a “Clean,” Efficient, Energy Option The issue of monetizing gas resources is becoming increasingly crucial for producing nations and oil and gas operators alike. Natural gas owes its growing appeal to its numerous advantages: 

It is a clean-burning fuel whose combustion generates no unburned residues, particulates or soot, and releases less greenhouse gas than the other fossil fuels.



Its high calorific value allows latest-generation power plants to achieve high energy efficiency using cogeneration or combined cycle configurations, limiting both energy consumption and atmospheric emissions. On the strength of these advantages, the share of natural gas in power generation is projected to rise from 20% in 2004 to nearly 25% in 2030. Liquefaction, Unlocking New Opportunities One of the main reasons for the emergence of the LNG industry is that it makes transporting

natural

gas

over

long

distances both

technically

and

economically feasible. This spells opportunity for both gas-producing and gasconsuming countries: 

Exporting LNG by carrier means that huge reserves of gas located far from major consumer regions can be tapped. Liquefaction creates new market opportunities, generating revenues that stimulate the economies of producing nations. In addition, liquefaction often contributes to the reduction of gas flaring associated with crude oil production, thus limiting greenhouse gas emissions.



The LNG value chain not only promotes the use of an energy source with a smaller environmental footprint than other fossil resources, it also addresses the concerns of consumer nations regarding their diversity of supply while reducing their energy dependence on countries that supply natural gas via pipeline.

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Unlike piped natural gas, a cargo of LNG can be diverted en route. This promotes the flexibility that consumer nations need to manage their supply, and enables producing nations to optimize the monetization of their assets. This flexibility has been spurred by the increase in short-term LNG trading tied to market deregulation.



That same flexibility is proving an advantage for some countries such as Brazil, which are counting on the forthcoming growth of this sector in an offshore context. Shipping the gas by LNG carrier on a regional (as opposed to a transoceanic) scale offers an alternative to the challenging and costly development of pipeline systems. LNG in Four Steps

Presence across the Value Chain, Including Marketing Most LNG is sold under long-term sale and purchase agreements between liquefaction plants and gas marketers and/or power generators. Signing these contracts is a vital prerequisite to building liquefaction facilities, because they determine the economic viability of the plant — an investment of several billion dollars. LNG trading also takes advantage of the spot and short-term markets, which

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emerged about a decade ago in conjunction with natural gas market deregulation in Europe and expansion in LNG production and shipping capacity. These fast-growing trading opportunities provide an increasing degree of flexibility to market players.

DISADVANTAGES OF LNG LNG operations are capital intensive. Upfront costs are large for construction of liquefaction facilities, purchasing specially designed LNG ships, and building regasification facilities. Methane, a primary component of LNG, is considered a greenhouse gas because it increases carbon levels in the atmosphere when released.

TRANSPORTATION OF LNG LNG is transported in specially designed ships with double hulls protecting the cargo systems from damage or leaks. There are several special leak test methods available to test the integrity of an LNG vessel's membrane cargo tanks. The tankers cost around USD 200 million each. Transportation and supply is an important aspect of the gas business, since natural gas reserves are normally quite distant from consumer markets. Natural gas has far more volume than oil to transport, and most gas is transported by pipelines. There is a natural gas pipeline network in the former Soviet Union, Europe and North America. Natural gas is less dense, even at higher pressures. Natural gas will travel much faster than oil through a high-pressure pipeline, but can transmit only about a fifth of the amount of energy per day due to the lower density. Natural gas is usually liquefied to LNG at the end of the pipeline, prior to shipping. Short LNG pipelines for use in moving product from LNG vessels to onshore storage are available. Longer pipelines, which allow vessels to offload LNG at a greater distance from port facilities, are under development. This requires pipe in pipe technology due to requirements for keeping the LNG cold. LNG is transported using both tanker truck, railway tanker, and purpose built ships known as LNG carriers. LNG will be sometimes taken to cryogenic temperatures to increase the tanker capacity. The first commercial ship-to-ship transfer (STS)

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transfers were undertaken in February 2007 at the Flotta facility in Scapa Flow with 132,000 m3 of LNG being passed between the vessels Excalibur and Excelsior. Transfers have also been carried out by Exmar Ship management, the Belgian gas tanker owner in the Gulf of Mexico, which involved the transfer of LNG from a conventional LNG carrier to an LNG regasification vessel (LNGRV). Prior to this commercial exercise LNG had only ever been transferred between ships on a handful of occasions as a necessity following an incident. PIPING FOR LNG The performance and economic advantages of vacuum insulation piping have been realized in many industries and applications for decades. Extensive and unnecessary boil-off gas, pipeline insulation maintenance and repair, and running and maintaining large compressors and/or reliquefiers no longer need to be common burdens and expenses for LNG plant and terminal operation. ADVANTAGES 

The double wall design acts as an added safety feature as a secondary barrier for the Liquefied Natural Gas carrier pipe.



VIP (Vacuum Insulated Pipe) can be installed underground and under water whilst MIP cannot.



Option for internal expansion bellows and loops (for thermal expansion and contraction) for underground and under water installations.



Pipe diameters up to 60”” are possible with an inner pipe constructed from stainless steel (typically ASTM Type 304/304L), whilst the outer jacket can be constructed from stainless or carbon steel depending on site conditions and specific requirements of the facility owners.



The vacuum level greatly reduces the conductive and convective heat transfer from the ambient surroundings into the cold LNG carrier pipe.



The annular space between the carrier and jacket pipes is fitted with a multiple layer radiation shielding system, which further reduces the heat transferred into the LNG piping

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LNG Dispenser Design The Cryogenic Fuels LNG dispenser unit is designed to perform a two-line vent fill with the vent gas being metered and recovered to the facility main bulk storage tank. The dispenser unit includes a density compensation metering subsystem, the pneumatically operated, fuel delivery shutoff valves, a 40 micron filter, two direct mass metering, flow meters, for liquid/vapor totalizing, and a back-pressure regulator that may be preset to provide operating pressures of 50 to 110 psi in the vehicle tank. The dispenser unit also includes an explosion-proof box that contains the start/stop switches, a methane gas detector, hazardous warning lights and the emergency stop button. Computer Controller The programmable system controller (PLC) for the dispenser is located in a nonhazardous area that must be located at least 70 ft. from the fuel storage and fuel dispensing area. This subsystem consists of the system electronic circuits that transmit the signals from various control components including the pump prime and pump start/stop commands and the signals from the liquid sensors. The station liquid sensors control the plumbing cool-down and the start of the pump motor. Liquid sensors are also installed in the dispenser and the fueling hose disconnect to control re-circulation flow and automatic fuel shut-off when the vehicle tanks are 100 % full. Fueling Disconnects

The Model C-1000-2 dispenser is also equipped with multiple fueling disconnects of different types to accommodate a variety of fuel tank receptacles. The vehicle fill process is initiated by depressing the "fueling start" button on the front of the console. A liquid sensor installed in the dispenser provides the signal to automatically terminate the fueling process when the fuel tank is filled to 90% of its maximum allowable volume. The fill process may also be terminated at any time by depressing an "emergency stop" switch, is also on the front of the dispenser console.

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CHAPTER 4 LIQUIFIED PETROLEUM GAS (LPG) INTRODUCTION Autogas is the common name for liquefied petroleum gas (LPG) when it is used as a fuel in internal combustion engines in vehicles as well as in stationary applications such as generators. It is a mixture of propane and butane. Autogas is widely used as a "green" fuel, as it decreases exhaust emissions. In particular, it reduces CO2 emissions by around 25% compared to petrol. One litre of petrol produces 2.3 kg of CO2 when burnt, whereas the equivalent amount of autogas (1.33 litre due to lower density of autogas) produces only 1.5 * 1.33 = 2 kg of CO2 when burnt. It has an octane rating (MON/RON) that is between 90 and 110 and an energy content (higher heating value—HHV) that is between 25.5 mega joules per litre (for pure propane) and 28.7 mega joules per litre (for pure butane) depending upon the actual fuel composition.

HISTORY OF LPG LPG was first identified as a significant component of petroleum in 1910. The story goes that a Ford Model T owner asked Dr. Walter O. Snelling, a chemist and explosives expert with the U.S. Bureau of Mines, why the gasoline he had purchased was half gone by the time he got home. The car owner thought the government should investigate because consumers were being defrauded, with the gasoline evaporating at a rapid rate. Who said consumer activism is a new idea? So, Snelling filled a glass jug with the gasoline from the car and discovered, on his way back to the lab, that vapours were forming in the jug causing the cork to keep popping out. In addition, the gasoline he had purchased was half gone by the time he got home. Using an old hot water heater and other miscellaneous pieces of laboratory equipment, Snelling built a contraption that could separate the gasoline into its liquid and gaseous components. Snelling discovered a large part of liquid gasoline was

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actually composed of LPG, including propane, butane, and other hydrocarbons. He began experimenting with these gases to find ways to control and capture them. American Gasol CompanySnelling soon realised that the LPG could be used for lighting, metal cutting, and cooking. That discovery marked the origin of the LPG industry. Snelling, in cooperation with others, created ways to liquefy the LPG during the refining of natural gasoline.

Together they established the American Gasol

Company, the first commercial marketer of LPG.

Snelling managed to produce

relatively pure propane by 1911 and, in 1913, his LPG technology was awarded a U.S. patent. Other methods and advances in technology followed. PRODUCTION OF LPG LP Gas (or LPG) stands for “Liquefied Petroleum Gas”. The term is widely used to describe two prominent members of a family of light hydrocarbons called “Natural Gas Liquids” (NGLs): propane (C3H8) and butane (C4H10). The other members of the NGLs family, ethane and condensates, have their own distinctive markets. The term “liquefied gas” may seem a contradiction in terms since all things in nature are either a liquid or a solid or a gas. Yet, liquidity is the unique character of LP Gas that makes it such a popular and widely used fuel. At normal temperature and pressure, LP Gas is gaseous. It changes to a liquid when subjected to modest pressure or cooling. In liquid form the tank pressure is about twice the pressure in a normal truck tyre, which means it is very safe when properly handled. LP Gas is a derivative of two large energy industries: the processing of natural gas liquids and the refining of crude oil. Natural gas processing When gas is drawn from the earth, it is a mixture of several gases and liquids. Commercial natural gas is mainly composed of methane. However, it also contains ethane, propane and butane in accordance with the specifications for natural gas in each country in which it is distributed. Therefore, before natural gas is marketed, some NGLs, including LP Gases (propane and butane) are separated out, depending on the”wetness” of the gas produced: NGLs represent 1 to 10% of the

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unprocessed gas stream. Some NGLs are also trapped in crude oil. In order to stabilise the crude oil for pipeline or tanker distribution, these “associated” or ”natural gases” are further processed into LP Gas. Worldwide, gas processing is the source of approximately 60% of LP Gas produced. Crude oil refining In an oil refinery, LP Gases are produced at various stages: atmospheric distillation, reforming, cracking and others. The LP Gas produced will be between 1 and 4% of crude oil processed. This yield will depend on the type of crude oil, the degree of sophistication of the oil refinery and the market values of propane and butane compared to other oils products. Worldwide, refining is the source of approximately 40% of LP Gas produced. Like all other hydrocarbons obtained from oil and gas, LP Gas has its own distinct marketing advantages and can perform nearly every fuel function as the primary fuels from which it is derived. Furthermore, LP Gas supply is growing faster than any other oil products. As a result, demand for LP Gas is steadily growing throughout the world and forecasts show this trend will continue. PROPERTIES



LPG is a liquid under pressure but a gas at ambient conditions.



Vapour LPG is twice as heavy as air.



Liquid LPG is half as heavy as water.



LPG is colorless.



LPG has a low boiling point of - 6°C



LPG has a narrow flammability range between 1.8 to 9.5% in air.



Flash point of LPG is -60°C.

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The approximate minimum ignition temperature of LPG is in the range 410°C to 580°C. LPG is odourless.



Ethyl Mercaptan is added as an odourant to detect LPG in case of leaks.



LPG is non-toxic.



It is lightly anaesthetic and can cause suffocation, if present in sufficiently high concentrations.



Liquid LPG can cause severe cold burns to the skin owing to rapid vapourisation and the consequent lowering of temperature

LPG STORAGE LPG storage – fixed tanks A liquefied petroleum gas storage tank, together with any associated pipework connecting the system to a combustion appliance providing space or water heating, or cooking facilities, should be designed, constructed and installed in accordance with the requirements set out in the LPGA Code of Practice. Below-ground tanks should be in accordance with Part 4 – ‘Buried/Mounded LPG Every tank should be separated from a building, boundary, or fixed source of ignition, to: in the event of fire, reduce the risk of fire spreading to the tank and enable safe dispersal in the event of venting or leaks. Tanks should be situated outdoors, in a position that will not allow accumulation of vapour at ground level. Ground features such as open drains, manholes, gullies and cellar hatches, within the separation distances given in column (A) of the table below should be sealed or trapped to prevent the passage of LPG vapour. LPG storage Cylinders Cylinders should be positioned on a firm, level base such as concrete at least 50mm thick or paving slabs bedded on mortar, and located in a well-ventilated position at ground level, so that the cylinder valves will be:

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a. at

least

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horizontally

and

300mm

vertically

from

openings

in

the buildings or from heat source such as flue terminals or tumble dryer vents b. At least 2m horizontally from untrapped drains, unsealed gullies or cellar hatches unless an intervening wall not less that 250mm high is present.

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LPG dispensing system

ABOVE GROUND Typical, module station with above ground tanks for LPG refueling consists of: 

Two tanks (each of 4,850 dm3 capacity);



Pumping unit with pump and electrical motor in EX execution - impeller pump or turbine pump;



LPG dispenser equipped optionally with: amount pre-selection system, operator’s calling pushbutton, multiple breaking up connections, stainless steel housing; module cooperating with cash register, filling hose (from 4 m to 8 m length)



Shut off and protecting - control fixtures and pipelines connecting tanks with pump and LPG dispenser

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UNDER GROUND Underground tank have following configurations: 

One tank of 6400 dm3; 6700 dm3; 9200 dm3; 10000 dm3; 15000 dm3; 20000 dm3 capacity; Tanks of 10000 dm3; 15000 dm3; 20000 dm3capacity offered by us are available in execution with bigger diameter that enables to select optimal tank to the field conditions, the bigger diameter the shorter tank.



Pumping unit with pump and electrical motor in Ex execution – turbine pump;



LPG dispenser optionally equipped with amount pre-selection operator’s calling pushbutton, multiple breaking up connections, stainless steel housing; module cooperating with cash register, filling hose (from 4 m to 8 m length);



Shut off and protecting - control fixtures and pipelines connecting tanks with pump and LPG dispenser;



Optionally, we equip station with: gas leakage detection; cathodic protection with protection operation signaling system.

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LPG Nozzles User-Friendly Single-Action Operation and Ergonomic Design Entire fueling operation is initiated by simply engaging nozzle to the receptacle with a single squeeze of the hand.Minimal force required to engage nozzle. Maximum durability. Designed specifically for frequent coupling and uncoupling. Heavy-duty brass, aluminum or stainless-steel construction provides excellent corrosion resistance in the harsh fueling environment Safety Will not dispense gas until securely engaged onto an appropriate receptacle. Once engaged, it will not disengage until released by operator.

LPG RECEPTACLES Body: Stainless steel Internal Parts: Stainless steel and brass

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Seals: Specially formulated polymers and elastomers specific to high-pressure NGV applications. Features Protective Rubber Dust Caps Nozzles Specifications: Min. Flow Rate: 1500 SCFM @ 3000 psi Temperature Range: -40° F to 250° F (-40° C to 120° C) Cv: LB = 0.91 LD = 0.85 LE = 0.83 MAWP: 5000 psi (345 Bar)

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Material Compatibility for LPG 

Buna-N (Nitrile): Buna-N, also known as Nitrile rubber, is a synthetic rubber copolymer of acrylonitrile (ACN) and butadiene.



Chemraz: Chemraz combines the resilience and sealing force of an elastomer with chemical resistance approaching that of PTFE.



Epichlorohydrin: Epichlorohydrin (ECO) has properties similar to nitrile rubber but with better heat and oil resistance as well as better low temperature flexibility.



Fluorocarbon: Fluorocarbon elastomer (FKM) material is also known by its tradename VITON or Fluorel.



Kalrez: Kalrez is the tradename for a perfluoroelastomeric material.



Hydrogenated Nitrile: Hydrogenated Nitrile Butadiene Rubber (HNBR) is also known as Highly Saturated Nitrile (HSN).



Polysulfide: Polysulfide was one of the first commercial synthetic elastomers.



Virgin Teflon: Because Teflon is a hard plastic rather than a stretchy elastomer, it is uncommon to see an o-ring that is made entirely of Teflon.



Vamac: Vamac is the tradename of a class of Ethylene Acrylic elastomer (AEM).

KPS LPG Pipe System

LPG, or Liquefied Petroleum Gas, is regarded as a green alternative to petrol in some countries, and sometimes benefitting from tax incentives which makes it an attractive choice for car owners. Recognizing the growing market for this "green" fuel in many countries. The LPG pipe is made of high density polyethylene or HDPE, and designed for the high pressures used in LPG distribution. Designed for pressures up to 25 bars and a pressure test of up to 40 bars, our LPG pipe meets the high standards of safety in the LPG industry. The permeation barrier and a conductive plastic liner ensure that there will be no

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permeation of the hydrocarbons, and that static electricity can dissipate safely.



With LPG Pipes You Get...

No corrosion. The LPG pipe with its protective liner is completely corrosion resistant. Steel pipes and other pipes may corrode both on the outside and on the inside, creating problems with particles damaging the dispensers, and possible leakages into the soil. Quick and easy installation. The LPG pipe is a semi flexible plastic pipe, easily rolled out into the trenches of the station from end to end, and then connected to the tank and dispensers. Although resistant and tough, the pipe can be bent on site to be fitted to tanks and dispensers. No welding or complicated installation procedures are needed, and the installation can be completed in less than one day! Lower cost and higher return on investment. Product and installation costs are kept at a minimum with the new LPG pipe. Since the estimated life time of the pipe is over 30 years, LPG pipes provide lower total cost of ownership and higher return on investment than any other LPG pipe on the market.

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TRANTPORTTION OF LPG

Transportation of LPG is done by either pipelines or truck containers. Gazeous hydrocarbons, in particular propane, butane and their mixtures are widely used as an alternative to fuel oil heating purposes. The storage and transportation of such gases, especially LPG (abbreviation of Liquefied Petroleum Gas), imposes stringent technical requirements. The material must be carefully selected, continual quality checks must be performed during manufacturing and comprehensive tests must be performed on completed tanks. The transport of LPG from the production places to the consumption places is done either by sea or by land transportation. The sea transportation means are called butaners or propaners. Among the land transportation means, we can find : LPG pipelines LPG rail tankers LPG road tankers LPG delivery trucks (bulk and cylinders) In Europe, in order to increase the competitivity of LPG, the supply costs have been decreased by rationalizing transport and in particular increasing the number of sea terminals.

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LPG is typically transported by dedicated vessels suitable for carrying pressurised, semi-pressurised or refrigerated LPG. The pressurised (18-bar, ambient temperatures) or semi-pressurised (5-8 bar, -10 to -20 degrees Celsius) LPG ships carry 3 – 10,000 m3 or 10 - 30,000 m3 respectively. Larger volumes require refrigerated transport solutions (ambient pressure, but at temperatures as low as -43 degrees Celsius for 100% Propane). Fully refrigerated vessels typically have cargo volumes ranging from 35,000 m3 up to 100,000 m3. Evaluating the markets for LPG transportation world-wide, a trend is developing towards the refrigerated transport of LPG in large volumes. The offshore terminal solution is suitable for all three types of transfer. The loading / un-loading (turnaround) cycle, including the mooring and departure procedures, can usually be achieved in about a day. ADVANTAGES AND DISADVANTAGES OF LPG LPG (Liquefied Petroleum Gas) LPG has many uses; from heating to vehicles. It is made up of hydrocarbon gases. When used for vehicles, LPG is a mixture of propane and butane (this is called autogas). When compressed, it turns into liquid form. 1L of LPG liquid is equivalent to 270L of LPG vapour. Advantages LPG is cheaper than petrol (up to 50%) It produces less exhaust emissions than petrol It is better for the engine and it can prolong engine life In some vehicles, it can provide better performance Has a higher octane rating than petrol (108 compared to 91)

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Disadvantages It isn't highly available The initial cost for converting your vehicle to LPG can cost up to $3000. However the average car can repay the cost of the conversion in about 2 years It has a lower energy density than petrol No new passenger cars come readily fitted with LPG (they have to be converted) The gas tank takes up a considerable amount of space in the car boot Liquid LPG (autogas with 60% propane and 40% butane) has an energy density of about 26.8MJ/L. LPG is not as available as petrol and diesel, but can be found at 45% of service stations in Australia (there are 3200 outlets). LPG in Australia is mainly refined locally. Burning 100L of LPG emits about 160kg of carbon dioxide into the atmosphere.

LPG ENGINE DEVELOPMENT AND FUEL KIT Engines Similar to natural gas, LPG forms easily a homogenous mixture with air. This combined with the relatively simple chemical structure of LPG, it burns cleanly and is well-suited for spark-ignition engines. For compression ignition (diesel) engines, LPG is not suitable as the sole fuel. LPG vehicles are available as OEM vehicles and as retrofit vehicles. Generally OEM vehicles perform better than retrofit vehicles. LPG is used mostly in bi-fuel vehicles, which start on gasoline. Spark ignition engines using gasoline can be converted to LPG or bi-fuel engines quite easily by changing the fuel system or adding a parallel fuel system for LPG. Liquid or gaseous LPG is sequentially injected in the inlet ports of an engine. The LPG-kit can be implemented in nearly all petrol cars. The

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advanced LPG vehicles have lambda control, which enables good catalyst performance. In spark ignition engines, similar compression ratios are typically used with LPG as with gasoline, even though the octane number of LPG (112 for propane, 94 for butane) is higher than that of gasoline. This is due to the fact that the combustion temperature is higher when LPG is used and this lowers the knock limit especially at high engine loads. Exceptions to this are the engines in which LPG is injected in liquid form. In bi-fuel cars, the upper limit for compression ratio is restricted by gasoline. Efficiency of LPG engines is similar to gasoline engines. When diesel engines, typically used in buses and trucks, are converted to LPG use, spark-ignition must be added. In addition, compression ratio must be reduced, combustion chamber must be reshaped and, of course, the whole fuel system must be replaced. It is, however, also possible to use LPG in diesel engines as an auxiliary fuel similar to methane. In so called gas-diesels, diesel is needed as ignition fuel and gas can be the main fuel. Gas-diesel engines work on the diesel process and energy efficiency is good. Dual fuel gas-diesel is more complicated and more difficult to control on transient operation than spark ignited gas engines. FUEL KIT The process of converting a car to run on propane is fairly demanding and requires a good knowledge of automotive systems in general to accomplish.* Several companies offer kits that include all the needed parts to perform the conversion. Those without the necessary know-how should try to find a local mechanic with experience in LP-gas conversions to get the job done. Although propane is very safe as an automotive fuel, if the system is not installed correctly, there can be safety problems. The first step is choosing a tank. Most conversions are dual-fuel conversions, meaning you won't be replacing your old fuel system, you'll simply be adding a second. As a result, the propane tank will take up some of the storage space in your car, usually in the trunk.

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Donut tank (left) and torpedo tank Tanks come in "torpedo" or "donut" form. Torpedo tanks generally have more capacity, but will take up more space in your car. Donut tanks are designed to fit in the spare tire well of your car. They are smaller tanks, and you'll have to sacrifice your spare tire. In larger vehicles, you could mount multiple tanks for increased capacity. Once the tank is bolted in, a fill point must be drilled into the car's body, usually near the gasoline fill point or at the back of the trunk. The ideal location is one that requires minimal piping to connect to the tank. The fuel lines themselves are copper tubes, which offer a certain amount of flexibility when the lines are routed. The tank must be connected to the fill point, and lines also have to run along the underside of the car up to the engine. A solenoid valve (LPG valve in the above diagram) must be installed on the fuel line in between the tank and the engine. This valve cuts the flow of LP gas when the car is running on gasoline and when the engine is shut off. It also has a filter built in that removes any dirt that may be in the fuel. The next major component is called a regulator, also referred to as a vaporizer. This device performs one of the functions that a carburetor handles in a gasoline engine - it uses heat from the car's cooling fluids to vaporize the propane into gas form. Another safety check occurs at the regulator, as well. It includes an electronic circuit that cuts the flow of gas if the engine stops or stalls. The regulator is usually smaller than a regular carburetor, so finding space for it in the engine compartment shouldn't be a problem. The other part of a carburetor's function is handled by a mixer mounted in the intake manifold. The mixer takes information from the car's sensors or ECU, and then it controls the amount of gas that flows into the cylinders.

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Dashboard fuel switch/gauge The system must then be wired into the car's electrical system, allowing for a functioning fuel gauge, as well as proper automatic switching between propane and gasoline (along with a dashboard-mounted manual switch). There must be connections to the car's ECU so that the engine controller can adjust for different fuel settings. Cars with an electronic injection system will probably need an electronic emulator. When the car is operating on LP gas, the fuel injectors will not be sending any information to the other sensors in the car -- this will light up the "check engine" light and give incorrect diagnostic readings. The emulator fakes the proper signals so the ECU can operate properly. Conversion kits come with more detailed instructions, but this is a basic overview of what needs to happen in a dual-fuel conversion.

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LPG COMBUSTION Compared with petroleum fuel, liquefied petroleum gas (LPG) demonstrates advantages in low CO₂ emission because of propane and butane, which are the main components of LPG, making H/C ratio higher. In addition, LPG is suitable for high efficient operation of a spark ignition (SI) engine due to its higher research octane number (RON). Because of these advantages, that is, diversity of energy source and reduction of CO₂, in the past several years, LPG vehicles have been widely used as the alternate to gasoline vehicles all over the world. Consequently, it is absolutely essential for the performance increase of LPG vehicles to comprehend the combustion characteristics of LPG and to obtain the guideline for engine design and calibration. LPG EMISSIONS The major harmful emissions from LPG engines are similar to those from other internal combustion engines: Carbon monoxide (CO) Hydrocarbons (HC) Nitrogen oxides (NOx) Unlike diesel engines, there are practically no particulate emissions from LPG engines. Concentration ranges of particular emissions are listed in Table 4. Emissions from LPG Engine CO

HC

vol. %

ppm C1

0.2 - 2 50-750

NOx vppm 250 - 2,000

Carbon monoxide is generated in the exhaust as the result of incomplete combustion of fuel. CO is a very toxic, colorless and odorless gas. LPG emissions may contain

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considerable amounts of CO. When engines operate in enclosed spaces, such as warehouses, buildings under construction, or tunnels, carbon monoxide can accumulate quickly and reach concentrations which are dangerous for humans. It causes headaches, dizziness, lethargy, and death. CO is usually the major concern whenever LPG engines are used indoors. Hydrocarbons are also a product of incomplete combustion of fuel. LPG emissions, because of the composition of fuel, contain only short chain hydrocarbons. They are not likely to contain toxic components which are found in gasoline HC emissions. Also the environmental impact of LPG hydrocarbon emissions (ozone reactivity contributing to smog) is much smaller than that of gasoline. However, hydrocarbon derivatives are responsible for the characteristic smell which is often a nuisance when LPG engines operate indoors. Nitrogen oxides are generated from nitrogen and oxygen under the high temperature and pressure conditions in the engine cylinder. NOx consists mostly of nitric oxide (NO) and some nitrogen dioxide (NO2). Nitrogen dioxide is a reactive gas, very toxic for humans. Accumulation of NOx in a warehouse atmosphere may be also detrimental for the stored goods. For example, only a few ppm of NOx in the ambient air can change the color of paper stock from white to yellowish. NOx emissions are also a serious environmental concern because of their ozone reactivity and important role in smog formation. LPG VEHICLES AROUND THE WORLD AND IN INDIA

What is Propane? Motor Fuel Propane, otherwise known as Liquefied Petroleum Gas (LPG), is produced as part of natural gas processing and crude oil refining. In natural gas processing, the heavier hydrocarbons that naturally accompany natural gas, such as LPG, butane, ethane, and pentane, are removed prior to the natural gas entering the pipeline distribution system. In crude oil refining, LPG is the first product that results

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at the start of the refining process and is therefore always produced when crude oil is refined. Propane is a gas that can be turned into a liquid at a moderate pressure, 160 pounds per square inch (psi), and is stored in pressure tanks at about 200 psi at 100 degrees Fahrenheit. When propane is drawn from a tank, it changes to a gas before it is burned in an engine. Propane has been used as a transportation fuel since 1912 and is the third most commonly used fuel in the United States, behind gasoline and diesel. More than four million vehicles fueled by propane are in use around the world in light-, medium-, and heavy-duty applications. Propane holds approximately 86 percent of the energy of gasoline and so requires more storage volume to drive a range equivalent to gasoline, but it is price-competitive on a cents-per-mile-driven basis. Benefits of Propane in Transportation Applications LPG has a long and varied history in transportation applications. It has been used in rural and farming settings since its inception as a motor vehicle fuel. Over time, propane has been used in several niche applications such as for forklifts, both inside and outside warehouses, and at construction sites. Use of propane can result in lower vehicle maintenance costs, lower emissions, and fuel costs savings when compared to conventional gasoline and diesel. Presently, domestic automakers have reduced their offerings of vehicles that can operate using propane and other gaseous fuels; this has placed renewed emphasis for the conversion or "upfitting" of new vehicles to operate on propane and compressed natural gas. Vehicle conversions in the 1970s started a very large upswing in the numbers of vehicles capable of using propane, as rising gasoline prices compelled drivers to find more economical fuel sources. The propane industry is once again focused on the conversion or upfitting of vehicles, to maintain the fuel as a viable motor fuel alternative that can provide both emission and petroleum displacement benefits, in the absence of original engine manufacturer (OEM) offerings.

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Where is Motor Fuel Propane Available in California? Approximately 1,200 facilities in California dispense propane. Nearly all of these facilities are used primarily to fuel residential and commercial applications such as heaters, recreational vehicles and barbecues. About half of all these facilities are capable of providing propane as a motor fuel, though only about 3 percent of all the fuel dispensed is used for transportation applications.

Since 2000, the California state fleet has purchased, and is now operating in daily use, nearly 1,600 bi-fuel (vehicles that can operation on either gasoline or LPG) Propane Ford F-150 pickup trucks. The potential use of propane in those vehicles constitutes the largest petroleum displacement for the state fleet; it could displace approximately 4.4 percent of the total fleet fuel use, if these vehicles were exclusively operated on propane. Accordingly, the California Energy Commission and the U. S. Department of Energy have provided funding to establish 25 motor fuel propane stations across the state. These stations are situated for convenient use by CalTrans and the Department of Water Resources fleets and for use by the public. The stations, operated by CleanFuel USA and Delta Liquid Energy, are unique from other propane filling stations. They have dispensers on the fueling island at a gasoline station, use fleet fueling cards or credit cards, and offer fuel that is priced competitively with gasoline or diesel on a fuel equivalency basis. Propane is a low-emission, economic and easily used fuel that can play an important role as an alternative, non-petroleum fuel for our state and the nation. Given the right conditions and incentives, propane can steadily displace a growing volume of petroleum fuels in California and therefore help provide a broader, more competitive transportation fuel market in the state.

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LPG VEHICLES IN INDIA

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CHAPTER 5 LIQUIFIED HYDROGEN INTRODUCTION Liquid hydrogen (LH2 or LH2) is the liquid state of the element hydrogen. Hydrogen is found naturally in the molecular H2 form. To exist as a liquid, H2 must be pressurized above and cooled below hydrogen's Critical point. However, for hydrogen to be in a full liquid state without boiling off, it needs to be cooled to 20.28 K (−423.17 °F/−252.87°C) while still pressurized. One common method of obtaining liquid hydrogen involves a compressor resembling a jet engine in both appearance and principle. Liquid hydrogen is typically used as a concentrated form of hydrogen storage. As in any gas, storing it as liquid takes less space than storing it as a gas at normal temperature and pressure. Once liquefied it can be maintained as a liquid in pressurized and thermally insulated containers. Liquid hydrogen consists of 99.79% parahydrogen, 0.21% orthohydrogen HISTORY 1756 - The first documented public demonstration of artificial refrigeration by William Cullen, Gaspard Monge liquefied the first gas producing liquid sulfur dioxide in 1784. Michael Faraday liquefied ammonia to cause cooling, Oliver Evans designed the first closed circuit refrigeration machine in 1805, Jacob Perkins patented the first refrigerating machine in 1834 and John Gorrie patented his mechanical refrigeration machine in 1851 in the US to make ice to cool the air, Siemens introduced the Regenerative cooling concept in 1857, Carl von Linde patented equipment to liquefy air using tile Joule Thomson expansion process and regenerative cooling in 1876, in 1885 Zygmunt Florenty Wróblewski published hydrogen's critical temperature as 33 K; critical pressure, 13.3 atmospheres; and boiling point, 23 K.

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PROPERTIES OF LIQUIFIED HYDROGEN

Property

Value

Symbol

H2

Melting Point

13.81 K

Boiling Point

20.28 K

Heat of Vaporization @ 0°C, 1.013 bar

445.6 kJ/kg

Specific Heat (Cp) @ 0°C, 1.013 bar

9.78 kJ/kg K

Viscosity

13.06 kg/m-s X 106

Thermal Conductivity (k)

118.5 mW/m-k

Critical Temperature

32.976 K

Critical Pressure

1.293 MPa

Temperature at Triple Point

13.803 K @ 7.04 MPa

Saturated Liquid Density (p) @ 0°C, 1.013 bar

70.97 kg/m3

Phase at Room Temperature (20°C)

Gas

PRODUCTION OF HYDEROGEN PHOTOCHEMICAL PRODUCTION OF HYDROGEN The production of renewable and non-polluting fuels via the direct conversion of solar energy into chemical energy remains a fascinating challenge for the end of this century. Among various interesting reactions, the splitting of water into molecular hydrogen and molecular oxygen by visible light (reaction 1) is potentially one of the most promising ways for the photochemical conversion and storage of solar energy. H20 = H2 + 1/202' (1) Indeed hydrogen is a valuable fuel: the free enthalpy needed in reaction 1 to produce one mole of H2, i.e., the energy stored per mole, is LlGg98 = 237.2 kJ . mol-I. Due to its small weight, the energy storage capacity of H2 per gram, 119000 J. g-I, is very high. It is, for example three times higher than the storage capacity of oil (40 000 J. g-I). Moreover, the water-splitting process has two other advantages.First the raw material water which is very cheap and second combustion of H2 in air which again gives water.

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Photochemical production ALGEA PRODUCTION OF HYDROGEN The biological hydrogen production with algae is a method of photobiological water splitting which is done in a closed photobioreactor based on the production of hydrogen by algae. Algae produce hydrogen under certain conditions. In 2000 it was discovered that if C. reinhardtii algae are deprived of sulfur they will switch from the production of oxygen, as in normal photosynthesis, to the production of hydrogen.

STORAGE OF HYDROGEN

In the case of on-board storage of hydrogen for vehicular applications, automobile manufacturers require lightweight, compact, safe, and cost-effective storage plus the

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ability to achieve a driving range of at least 300 miles. The 300-mile driving range requires 5-10 kg of usable hydrogen depending upon the size of the vehicle. Although various hydrogen storage technologies are presently available, none completely satisfies all of the auto industry requirements. In fact, finding a solution to the hydrogen storage problem is considered by many to be the foremost challenge for the hydrogen economy. Hydrogen can be stored in three ways: 

As a compressed gas in high-pressure tanks.



As a liquid in tanks (stored at -253°C).



As a solid by either absorbing or reacting with metals or chemical compounds or storing in an alternative chemical form.

To meet the storage challenge, basic research is needed to identify new materials and to address a

Air Products LH2 tanker with Shuttle Atlantis (Photo: Air Products)

host of associated performance and system issues. Issues include operating pressure and temperature; the life span of the storage material (stability); the requirements for hydrogen purity imposed by the fuel cell; the reversibility of hydrogen uptake and release; the refueling conditions of rate and time; the hydrogen delivery pressure; overall safety, toxicity, and system-efficiency and cost. No material available today comes close to meeting all the requirements for onboard storage of hydrogen for fueling a fuel cell/electric vehicle.

Experimental test bed for evaluation of zero-boil-off cryogenic sys, FSEC H2 Lab,

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These requirements are often contradictory to each other (like the need for high specific energy and high energy density), and the requirement to simultaneously address these issues adds to the magnitude of the challenge. In fact, some of the requirements for onboard hydrogen storage seem unattainable especially with gaseous or liquid methods. Storage of hydrogen in chemical compounds offers a much wider range of possibilities to meet the transportation requirements, but no single material investigated to date exhibits all the necessary properties. The storage solution requires breakthroughs in materials performance that can only come from innovative and basic research that looks beyond the materials considered, to date. The exacting demands on storage capacity, charge and discharge conditions, stability, and cost span the traditional disciplines of chemistry, physics, materials science and engineering. The fundamental factors that control bond strength, desorption kinetics, degradation due to cycling, and the role of nanosize and nanostructure in bonding and kinetics must be researched and new materials found. At present, only three systems for on-board hydrogen storage are close to commercialization. They are compressed gas at high pressures (5,000 to 10,000 psi in composite cylinders), liquid hydrogen which requires a cryogenic temperature of 253 ° C, and materials-based storage in solids which involves the use of metal hydrides, carbon-based materials/high surface area sorbents, and/or chemical hydrogen storage. The current status of various storage technologies in terms of weight, volume and costs is given below. These systems show a three to eight times performance gap in meeting the DOE goals. Weight (kwh/kg)

Volume (kwh/L)

Cost ($/kwh)

Chemical Hydrides

1.6

1.4

$8

Complex Metal Hydrides

0.8

0.6

$16

Liquid Hydrogen

2.0

1.6

$6

10,000-psi Gas

1.9

1.3

$16

DOE Goals (2015)

3.0

2.7

$2

Storage Technologies

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ACTIVATED CARBON HYDROGEN STORAGE With hydrogen atoms consisting of just a single electron and single proton, its gaseous form made up of two hydrogen atoms can be hard to contain. Hydrogen storage, along with hydrogen production and the lack of infrastructure, remains a major stumbling block in efforts to usher in hydrogen as a replacement for hydrocarbon-based fuels in cars, trucks and even homes. But with the multiple advantages hydrogen offers, developing hydrogen storage solutions has been the focus of a great deal of research. Now an MIT-led research team has demonstrated a method that could allow hydrogen to be stored inexpensively at room temperature. Hydrogen storage solutions fall into one of two technologies; physical storage where compressed hydrogen gas is stored under pressure or as a liquid; and chemical storage, where the hydrogen is bonded with another material to form a hydride and released through a chemical reaction. Physical storage solutions are more established technologies but offer significant problems when looking at using hydrogen to fuel vehicles. Compressed hydrogen gas needs to be stored under high pressure - current hydrogen fuel cell vehicles such as the Mercedes-Benz F-Cell store hydrogen at 5,000 or 10,000 psi - which requires heavy tanks that add to the weight of a vehicle. Meanwhile, liquid hydrogen boils at -253°C (-423°F) so it needs to be stored cryogenically with heavy insulation and actually contains less hydrogen compared with the same volume of gasoline. Although they allow hydrogen to be stored at much lower pressures, chemical storage solutions that bond hydrogen to a highly porous, sponge-like material such as a metal hydride generally require high temperatures to release their hydrogen content because most metal hydrides bind with hydrogen very strongly. Previous research efforts have shown that a Rhodium-based material could store hydrogen at room temperature and would release the hydrogen when a small electric current was applied. Now an MIT-led research team has demonstrated that activated carbon can also store hydrogen under similar conditions and can release the hydrogen by simply releasing the pressure.

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The activated carbon incorporates a platinum catalyst that allows the hydrogen atoms to bond directly to the surface of carbon particles and be released when needed. Because it allows hydrogen to be stored at atmospheric pressure and room temperature, storage tanks could be made much lighter, cheaper and safer, thereby making them practical and economically viable for hydrogen-powered cars, say the researchers. To assess hydrogen's interaction with the activated carbon storage material, the research team used a technique called inelastic neutron scattering (INS). This method provided the first evidence that a phenomenon called the "spillover effect" was involved where, with platinum particles acting as a catalyst, hydrogen atoms split off from their molecules and diffuse through the carbon, where they bond with its surface. Sow-Hsin Chen, MIT professor emeritus in the Department of Nuclear Science and Engineering and senior author of a paper describing the new method, says it should make it possible to increase the storage capacity of the activated carbon material by fine-tuning the size and concentrations of the particles of platinum and carbon. The team also hopes to identify a catalyst that isn't quite as expensive as platinum. Once the storage system has been tuned to achieve the desired capacity, Chen says it should be capable of storing hydrogen under moderate pressure - possibly around 500 psi - and release the gas on demand by simply releasing the pressure. This is because when the hydrogen molecules are broken down into atoms using the spillover effect, they bind with the activated carbon with much less energy. HARZARD WITH LH2 Hydrogen is the most abundant element in the universe; however, here on the surface of the Earth, pure hydrogen gas is relatively rare. That's because hydrogen gas -- which is usually found in molecular form, with two hydrogen atoms bound together to form H2 -- is so light that, if not contained, it will rise rapidly to the top of the Earth's atmosphere and escape into space. Most hydrogen on the Earth's surface is bound together with other types of atoms as molecules that form various substances. For example, H2O, better known as water, and CH4, also known as methane, both contain hydrogen molecules. Before it can be used as a fuel, the

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hydrogen must first be extracted from these substances and then contained, usually in highly compressed liquid form. Are there dangers associated with pure hydrogen? To put it simply, yes. When liquid hydrogen is stored in tanks, it's relatively safe, but if it escapes there are associated hazards. Topping the list of concerns is hydrogen burns. In the presence of an oxidizer -oxygen is a good one -- hydrogen can catch fire, sometimes explosively, and it burns more easily than gasoline does. According to the American National Standards Institute, hydrogen requires only one 10th as much energy to ignite as gasoline does. A spark of static electricity from a person's finger is enough to set it off. Ideally, no oxygen should be present in the liquid hydrogen tanks in a fuel cell vehicle, but trace amounts of air may contaminate the hydrogen supply. If the hydrogen should escape, it will immediately come into contact with the oxygen in air. Another concern is that hydrogen flames are nearly invisible. When hydrogen catches fire, the flames are so dim and hard to see that they're both hard to avoid and hard to fight. Next, there's the potential for hydrogen to asphyxiate people. Hydrogen isn't poisonous, but if you should breathe pure hydrogen you could die of asphyxiation simply because you'll be deprived of oxygen. Worse, you won't necessarily know that you're breathing hydrogen because it's invisible, odorless and flavorless -- much like oxygen. The final concern that we want to mention here is that liquid hydrogen is cold. Because it's highly compressed, liquid hydrogen is extremely cold. If it should escape from its tank and come in contact with skin it can cause severe frostbite.

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ADVANTAGES AND DISADVANTAGES OF LIQUID HYDEROGEN The Advantages and Disadvantages of Liquid Hydrogen Advantages

"Hydogen highways are future for the United States" ~ George W. Bush, 2003 State of Union Address That's exactly what US former president, George Bush stated. And to me, if a president said that, then the entire country should be saying the same thing with him! Furthermore, as soon as Bush stated the plans for hydrogen highways to Arnold Schwarzenegger, guess what he replied? He proudly stated two things. Firstly, he announced plans to put hydrogen fuel stations all up and down the West Coast, so that Hydrogen vehicles could easily gas up, and have the ability to move around the west. And secondly, he convinced General Motors to build a Hydrogen Hummer! How extraordinary is that?!

Due to this, there must be many advantages: Liquid Hydrogen is the cleanest fuel available. While running, it produces zero emissions. Liquid Hydrogen is natural; it can be made.

Whereas, Fossil Fuels have to be

extracted. The process is simple. See the Liquid Hydrogen page for more... Hydrogen is the lightest element occurring on Earth, and still contains a large amount of energy within it. In fact, Liquid Hydrogen weighs less than petroleumbased fuels. It also has the best and highest energy-to-weight ratio of all fuels. Hydrogen's chemical and physical properties make it a good contender for fuel

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Also Liquid Hydrogen powered cars can last for quite a while. Did you know that the fuel cells for vehicles that have been tested have already run for 5,000 hours? This would enable a car to be driven for almost 200,000 miles at an average speed of 40 mph! Well...obviously, it's renewable! Hydrogen stores approximately 2.8 times the energy per unit mass as gasoline "Liquid Hydrogen is the fuel for the future! It is clean burning." Disadvantages If truth be told, there are very minor disadvantages of Liquid Hydrogen that can be easily improved as the years go on: Liquid Hydrogen has a very low density. Therefore, the size of a gasoline tank is three times less the amount, compared to a liquid hydrogen tank. Liquid Hydrogen has a high flammability range. But, there are solutions to preventing this. For example, you can (and people have) add a ventilation system to exhaust the explosion mixture to the atmosphere. Also, if the insulation isn't perfect the hydrogen will gradually evaporate at a rate of 1.6% per day. (However, see Conclusion for a solution to this.) Presently, petrol is almost half the price of Liquid Hydrogen, mainly due to fluctuant economic benefits and oppositions (such as the oil industry). On average, petrol is about $3.89 U.S. per gallon; whereas, liquid hydrogen is about $6 U.S. per gallon. However, it is almost certain that this figure will change in the next 5 years.

Hydrogen for transportation Hydrogen is not an independent source of energy, but can be used as fuel, produced on the basis of several sources of energy. Hydrogen does not pollute, since the exhaustion is only water. The good thing about hydrogen is that it can be used to store a surplus of renewable energy which then can be used in days, where there is a lower production. Wind mills can have a fluctuating production of electricity, but it can be stored with the use of

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hydrogen. At Folkecenter we produce hydrogen by using electrolysis, that is fission of electricity in water. As the only place in Denmark has Folkecenter the whole wind-hydrogen-car chain with electrolysis plant at 20 kW, storage of hydrogen and filling station for tanking of cars with hydrogen. Folkecenter was the first in Denmark with a hydrogen production plant, storage and filling system. During 2007 will the filling system be exchanged with a top modern plant. 2 times in a row has Folkecenter been the first to have a public hydrogen filling plant. Hydrogenlink Hydrogen Link Denmark is a national network for research, development and demonstration of hydrogen and fuel cell technologies for transportation with the purpose of advancing a Danish infrastructure of hydrogen filling stations and a widespread use of fuel cell vehicles, beginning with niche transportation and in long term road transportation. Folkecenter is a part of the Hydrogen Link network, which is a chain of filling stations all over Denmark that is supposed to make it possible to drive from the Danish-German border and far up in Norway. LH2 dispensing The volumetric energy density of hydrogen gas under ambient conditions is much lower than that of gasoline or diesel (cf. section 1.2). Hydrogen is therefore compressed in order to reduce the size of the filling station storage, to keep space requirements on board the vehicle at a reasonable level, and to ensure enough range for daily bus operation. This is not entirely new as it also applies to natural gas, but the volumetric energy density of hydrogen compared to methane – the most important constituent of natural

gas

–

is

more

than

three

times

lower.

One solution for compensating this disadvantage is to move to higher onboard gas pressures, from 200 bar (standard technology for mobile applications so far, both hydrogen and natural gas) to 350 bar, and most likely 700 bar in the future. Previous

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hydrogen bus demonstration project, HyFLEET: CUTE, was the first major trial which followed this 350 bar concept, requiring a technology step for the refueling infrastructure. The main components of a filling station for compressed gaseous hydrogen (CGH2) storage and dispensing are compressor (one or more), storage vessels and dispenser with filling nozzle. Liquid hydrogen (LH2) performs about as well as natural gas at 200 bar regarding volumetric energy density, even when considering the volume for the insulation of the cryogenic tank. Liquid hydrogen storage can be employed both at stations and in vehicles. One of the CHIC cities, London, will demonstrate external supply of LH2 and its storage on site at the station. Liquid onboard storage is not realised in CHIC as buses have sufficient room on the roof to accommodate enough 350 bar pressure vessels to enable the desired range. The main components for a filling station for CGH2 dispensing with LH2 storage are cryogenic vessel, cryogenic pump for pressurising the liquid, vaporiser and dispenser.

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LH2 EMISSIONS Hydrogen fuel cell vehicles emit only water vapor, warm air, and some hydrogen, which are not concerns for air quality. Similar to electricity, hydrogen is an energy carrier that can be produced from various feedstocks. These feedstocks and production methods should be considered when evaluating hydrogen emissions. BMW LIQUID HYDROGEN CARS Hydrogen 7 – the first series-developed vehicle with a hydrogen combustion engine. In the long term, the BMW Group is working towards hydrogen as the fuel source of the future. The BMW Group presented the BMW Hydrogen 7 in November 2006 in Berlin, the world’s first hydrogen-driven luxury Sedan. This vehicle is practically emission-free and suitable for everyday use. The new model, based on the BMW 760Li, represents a milestone en route to a new era of sustainable mobility. The BMW Hydrogen 7 is powered by a combustion engine capable of running on both hydrogen and petrol. This vehicle has gone through the entire series development process and is the result of a clearly-defined strategy, which already enables the BMW Group to put tomorrow’s hydrogen technology to use in today’s vehicles. In addition, the new technology will be able to benefit from the whole range of efficiency improvement measures right up to the full hybrid version. The BMW Hydrogen 7 is capable of covering over 200 kilometres powered by hydrogen and a further 500 kilometres in the conventional petrol mode. The BMW Hydrogen 7 holds approximately eight kilograms of liquid hydrogen and its conventional petrol tank has a capacity of 74 litres. The introduction of the BMW Hydrogen 7 by the BMW Group will create momentum to increase hydrogen supply coverage. At the same time, the BMW Group calls on the relevant networking partners in the fields of politics, science, research and business to build up infrastructures and promote technologies related to hydrogen as an energy source.

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Liquid Hydrogen in India Status of Hydrogen-based Technologies in India Production The Banaras Hindu University (BHU); Murugappa Chettiar Research Centre (MCRC), Chennai; and IIT, Kharagpur are among the leading research groups working on biological, biomass, and other renewable energy routes to produce hydrogen. With R&D support from the MNES, the MCRC has demonstrated hydrogen production in batch-scale from distillery waste. The pilot plant is able to produce up to 18 000 liters of hydrogen per hour. Storage The BHU, IIT Chennai, and the National Physical Laboratory are working on the hydrogen storage methods. The BHU has developed various types of metal hydrides with storage capacities of up to 2.4 weight%. It has also demonstrated the use of 1.6% weight storage in metal hydride on a pilot scale. Hydrogen-Fuelled Vehicles Hydrogen-operated motorcycles and three-wheelers have been developed and demonstrated. The BHU has modified a commercially available motorcycle (100 cc, four strokes) and a three-wheeler (175 cc, four strokes) to operate on hydrogen as a fuel. Liquid hydrogen for Future Forget trying to shove gaseous hydrogen into porous materials for safe storage: the future of the clean-fuel economy lies in carrying hydrogen as a liquid, argues Robert Crabtree of Yale University, New Haven. This means that cars running on fuel cells, which run on hydrogen and oxygen and produce only water as a byproduct, could fill up at stations using roughly the same liquid-fuel infrastructure that already exists. High-pressure gaseous hydrogen, which is potentially dangerous, could be taken completely out of the public sphere. And there would be no need for totally new distribution networks and fuel-delivery systems.

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"By using a liquid, we simplify the engineering," says Crabtree, who told the American Chemical Society meeting in Boston, Massachusetts, this week about his work developing nitrogen-packed organic liquids that hold and release hydrogen. Most research on hydrogen storage and transport has focused on materials called metal hydrides and, recently, on metal-organic-frameworks (MOFs)—incredibly porous materials that can be stuffed full of gas. But getting enough hydrogen into these frameworks to make a fuel tank of reasonable size and weight is problematic, and getting the fuel in and out would require novel fuelling systems. Instead, Crabtree envisages a system that uses a standard petrol tank containing an organic liquid. This liquid would be passed through a heated module containing a catalyst, which would unlock hydrogen and release it a little at a time to be used as fuel. The remaining dehydrogenated liquid would then be removed at a filling station and whisked away to be reprocessed — the liquid can be hydrogenated and rehydrogenated repeatedly, making it re-usable. Meanwhile the tank would be quickly refilled with fresh, hydrogenated liquid. The main problem with such liquids is that it usually requires high temperatures (an increase of about 600 degrees Celsius) to unlock the hydrogen—not very practical in a car. Crabtree proposes getting around this by incorporating nitrogen into his organic liquids. Nitrogen binds to hydrogen less strongly than carbon does, and the presence of nitrogen within a carbon-based ring weakens the remaining C-H bonds. These weakened bonds make it easier to get hydrogen out as the liquid passes over a catalyst, and lower operating temperatures would be needed—the material only needs to be raised by 50 degrees Celsius. Most hydrogen producers claim that public concerns about the safety of highpressure

gas

is

one

of

the

reasons

for

their

interest

in

liquids.

But Peter Edwards, a hydrogen-storage expert at Oxford University, UK, is less convinced

that

we

need

to

worry

about

gaseous

hydrogen

storage.

"High-pressure containment technology advances have been remarkable," he says; he has seen a full high-pressure hydrogen tank sit on a bonfire without incident.

But this doesn't mean liquid technologies should be dismissed. "All potential

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innovative chemical routes to effective hydrogen storage materials—solid or liquid— are highly important," says Edwards

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CHAPTER 6 BIO FUELS Renewable Natural Gas (Biogas) Biogas—also known as biomethane, swamp gas, landfill gas, or digester gas—is the gaseous product of anaerobic digestion (decomposition without oxygen) of organic matter. In addition to providing electricity and heat, biogas is useful as a vehicle fuel. When processed to purity standards, biogas is called renewable natural gas and can substitute for natural gas as an alternative fuel for natural gas vehicles. Biogas is usually 50% to 80% methane and 20% to 50% carbon dioxide with traces of gases such as hydrogen, carbon monoxide, and nitrogen. In contrast, natural gas is usually more than 70% methane with most of the rest being other hydrocarbons (such as propane and butane) and traces of carbon dioxide and other contaminants. More than half the gas used in Sweden's 11,500 natural gas vehicles is biogas. Germany and Austria are targeting 20% biogas in natural gas vehicle fuel. In the United States, biogas vehicle activities have been on a smaller scale. Production Biogas is a product of decomposing organic matter, such as sewage, animal byproducts, and agricultural, industrial, and municipal solid waste. Biogas must be upgraded to a purity standard to fuel vehicles and be distributed via the existing natural gas grid. Biogas from Landfills Landfills are the third-largest source of human-related methane emissions in the United States. Methane can be captured from landfills and used to produce biogas. Methane gas collection is practical for landfills at least 40 feet deep with at least 1 million tons of waste. Find examples of landfills using biogas for vehicle fuel from the Sanitation Districts of Los Angeles County.

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Biogas from Livestock Operations Biogas recovery systems at livestock operations can produce renewable energy in cost-effective ways. Animal manure can be collected and delivered to an anaerobic digester to stabilize and optimize methane production. The resulting biogas can be used to fuel natural gas vehicles. The U.S. Environmental Protection Agency (EPA) estimates 8,200 U.S. dairy and swine operations could support biogas recovery systems with the potential to generate more than 13 million megawatt-hours and displace about 1,670 megawatts of fossil fuel-fired generation collectively per year. Biogas recovery systems are also feasible at some poultry operations. An example of converting livestock manure to biogas to fuel vehicles is the Western United Resource Development project. Distribution After biogas is produced, it must be refined to meet pipeline specifications. Currently, there are no specifications for natural gas as a vehicle fuel. Refining biogas means increasing the proportion of methane and decreasing the proportion of carbon dioxide and contaminants through absorption, adsorption, membrane separation, or cryogenic separation. Renewable natural gas can be distributed via existing natural gas distribution routes. Because these technologies are not developed and tested fully yet, distributing renewable natural gas via the pipeline grid is not common practice. Benefits Biogas can be an alternative to conventional transportation fuels. The benefits of biogas are similar to the benefits of natural gas. Additional benefits include:

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Increased Energy Security—Biogas offsets non-renewable resources, such as coal, oil, and fossil fuel-derived natural gas. Producing biogas creates U.S. jobs and benefits local economies. Fewer Emissions—Biogas reduces emissions by preventing methane release in the atmosphere. Methane is 21 times stronger than carbon dioxide as a greenhouse gas. Better Economics—Biogas reduces the cost of complying with EPA combustion requirements for landfill gas. Cleaner Environment—producing biogas through anaerobic digestion reduces landfill waste and odors, produces nutrient-rich liquid fertilizer, and requires less land than aerobic composting. Research and Development Research and development efforts are reducing the costs of biogas production and purification, producing higher-quality natural gas from biogas, and evaluating the performance of biogas-fueled vehicles. Some federal and state programs assist in these efforts, including EPA's Landfill Methane Outreach Program and AgSTAR Program. Learn more about landfill gas research and development projects from the Natural Gas Vehicle Technology Forum.

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Methanol Methanol (CH3OH), also known as wood alcohol, is an alternative fuel under the Energy Policy Act of 1992. As an engine fuel, methanol has chemical and physical fuel properties similar to ethanol. Methanol use in vehicles has declined dramatically since the early 1990s, and automakers no longer manufacture methanol vehicles in the US. Production This fuel is generally produced by steam-reforming natural gas to create a synthesis gas. Feeding this synthesis gas into a reactor with a catalyst produces methanol and water vapor. Various feedstocks can produce methanol, but natural gas is currently the most economical. Benefits Methanol can be an alternative to conventional transportation fuels. The benefits of methanol include: Lower Production Costs—Methanol is cheap to produce relative to other alternative fuels. Improved Safety—Methanol has a lower risk of flammability compared to gasoline. Increased Energy Security—Methanol can be manufactured from a variety of carbon-based feedstocks, such as coal. Its use could also help reduce U.S. dependence on imported petroleum. Research and Development Methanol was marketed in the 1990s as an alternative fuel for compatible vehicles. At its peak, nearly 6 million gasoline gallon equivalents of 100% methanol and 85% methanol/15% gasoline blends were used annually in alternative fuel vehicles in the United States. The Massachusetts Institute of Technology is researching the future of natural gas (PDF) as a feedstock to enable more widespread adoption of methanol as a transportation fuel.

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The National Renewable Energy Laboratory is researching ways to validate methanol fuel cell technology to use methanol for fuel cell vehicles. ETHANOL Ethanol Fuel Basics Related Information National Biofuels Action Plan (PDF) Ethanol is a renewable fuel made from various plant materials collectively known as "biomass." More than 95% of U.S. gasoline contains ethanol in a low-level blend to oxygenate the fuel and reduce air pollution. Ethanol is also available as E85, or high-level ethanol blends. This fuel can be used in flexible fuel vehicles, which can run on high-level ethanol blends, gasoline, or any blend of these. There are several steps involved in making ethanol available as a vehicle fuel: Biomass feedstocks are grown, collected and transported to an ethanol production facility Ethanol is produced from feedstocks at a production facility and then transported to a blender/fuel supplier Ethanol is mixed with gasoline by the blender/fuel supplier and distributed to fueling stations. Ethanol as a vehicle fuel is not a new concept. Henry Ford and other early automakers suspected it would be the world's primary fuel before gasoline became so readily available. Today, researchers agree ethanol could substantially offset our nation's petroleum use. In fact, studies have estimated that ethanol and other biofuels could replace 30% or more of U.S. gasoline demand by 2030. The use of ethanol is required by the federal Renewable Fuel Standard (RFS).

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Fuel Properties Ethanol (CH3CH2OH) is a clear, colorless liquid. It is also known as ethyl alcohol, grain alcohol, and EtOH. Ethanol has the same chemical formula regardless of whether it is produced from starch- and sugar-based feedstocks, such as corn grain (as it primarily is in the United States), sugar cane (as it primarily is in Brazil), or from cellulosic feedstocks (such as wood chips or crop residues). Ethanol has a higher octane number than gasoline, providing premium blending properties. Minimum octane number requirements prevent engine knocking and ensure drivability. Low-level ethanol blends generally have a higher octane rating than unleaded gasoline. Low-octane gasoline is blended with 10% ethanol to attain the standard 87 octane requirement. Ethanol is the main component in high-level ethanol blends. (See E85 Specification to learn more.) Per unit volume, ethanol contains about 30% less energy than gasoline. E85 contains about 25% less energy than gasoline. High-level ethanol blends contain less energy per gallon than does gasoline, to varying degrees, depending on the volume percentage of ethanol in the high-level blend. Ethanol Energy Balance In the United States, ethanol is primarily produced from the starch in corn grain. Recent studies using updated data about corn production methods demonstrate a positive energy balance for corn ethanol, meaning that fuel production does not require more energy than the amount of energy contained in the fuel Cellulosic ethanol, which is produced from non-food-based feedstocks, is expected to improve the energy balance of ethanol, because non-food-based feedstocks are anticipated to require less fossil fuel energy to produce ethanol. Biomass used to power the process of converting non-food-based feedstocks into cellulosic ethanol is also expected to reduce the amount of fossil fuel energy used in production. Another potential benefit of cellulosic ethanol is that it results in lower levels of life cycle greenhouse gas emissions. E85 Specification

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ASTM International developed a specification for gasoline-ethanol blends containing 51% to 83% ethanol that address proper vehicle starting, operation, and safety in varying temperature conditions. The table below shows the requirements of the ASTM D5798 Standard Specification for Ethanol Fuel Blends for Flexible-Fuel Automotive Spark-Ignition Engines. Fuel suppliers should specify meeting the requirements of the specification as a prerequisite in their supply contracts, so that they can guarantee their product is ASTM-compliant. Like gasoline and diesel fuel, E85 and other ethanol-gasoline blends are adjusted seasonally and geographically to ensure proper starting and performance. For example, E85 sold during colder months often contain lower levels of ethanol to produce the vapor pressure necessary for starting in cold temperatures. For this reason, fueling site operators offering ethanol blends typically cannot carry over summer-blend E85 in the winter months. They must instead "blend down" any remaining summer fuel to meet the ASTM specification’s requirements for winter temperature conditions. This can be done with relative ease by adding additional gasoline to the storage tank. On the other hand, there is no concern with carrying over winter fuel into the summer months because flexible fuel vehicles can operate on any blend of ethanol and gasoline in warm weather. For retail service stations, seasonal fuel adjustments are handled automatically at the wholesale fuel terminal. Ethanol Production and Distribution Ethanol is a domestically produced alternative fuel that's most commonly made from corn. It can also be made from cellulosic feedstocks, such as crop residues and wood—though this is not yet common. U.S. ethanol production is predominately concentrated in the Midwest because of its proximity to corn production. Plants outside the Midwest typically receive corn by rail and are located near large markets for ethanol. Production Today, U.S. ethanol is primarily produced from starch-based crops, such as corn. Cellulosic ethanol production volumes are very small by comparison. Several commercial cellulosic ethanol production plants are under construction, and intensive

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research and development is rapidly advancing the state of cellulosic ethanol technology. Starch- and Sugar-Based Ethanol Production Most ethanol in the United States is produced from starch-based crops by dry- or wet-mill processing. More than 80% of ethanol plants are dry mills due to lower capital costs. Dry-milling is a process that grinds corn into a flour and ferments it into ethanol with co-products of distillers grains and carbon dioxide. Wet-mill plants primarily produce corn sweeteners, along with ethanol and several other co-products (such as corn oil and starch). Wet mills separate starch, protein, and fiber in corn prior to processing these components into products, such as ethanol. Cellulosic Production Making ethanol from cellulosic feedstocks—such as grass, wood, and crop residues—is more challenging than using starch-based crops. There are two primary pathways to produce cellulosic ethanol: biochemical and thermochemical. The biochemical process involves a pretreatment to release hemicellulose sugars followed by hydrolysis to break cellulose into sugars. Sugars are fermented into ethanol and lignin is recovered and used to produce energy to power the process. The thermochemical conversion process involves adding heat and chemicals to a biomass feedstock to produce syngas, which is a mixture of carbon monoxide and hydrogen. Syngas is mixed with a catalyst and reformed into ethanol and other liquid co-products. See Process Design and Economics for Biochemical Conversion of Lignocellulosic Biomass to Ethanol: Dilute-Acid Pretreatment and Enzymatic Hydrolysis of Corn Stover (PDF) and Process Design and Economics for Biochemical Conversion of Lignocellulosic Biomass to Ethanol: Thermochemical Pathway by Indirect Gasification and Mixed Alcohol Synthesis (PDF) to read updated studies about the conversion process. Distribution Most U.S. ethanol plants are concentrated in the Midwest, but gasoline consumption is highest along the East and West Coasts (use TransAtlas to see the location of ethanol plants). This presents ethanol producers with unique distribution challenges.

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According to the U.S. Department of Agriculture, 90% of ethanol is transported by train or truck. The remaining 10% is transported by barge or pipeline. To put this into perspective, a tanker truck can carry 8,000 to 10,000 gallons of ethanol, and one rail car can carry approximately 30,000 gallons of ethanol. Ethanol Pipelines Delivering ethanol by pipeline is the most desirable option, but ethanol's affinity for water and solvent properties require use of a dedicated pipeline or significant cleanup of existing pipelines. Ethanol Benefits and Considerations Ethanol is a renewable, domestically produced transportation fuel. Whether used in low-level blends, such as E10 (10% ethanol, 90% gasoline), or in E85 (a gasolineethanol blend containing 51% to 83% ethanol, depending on geography and season), ethanol helps reduce imported oil and greenhouse gas emissions. Like any alternative fuel, there are some considerations to take into account when contemplating the use of ethanol. Fuel Economy and Performance A gallon of ethanol contains less energy than a gallon of gasoline. The result is lower fuel economy than a gallon of gasoline. The amount of energy difference varies depending on the blend. For example, E85 has about 27% less energy per gallon than gasoline (mileage penalty lessens as ethanol content decreases). However, because ethanol is a high-octane fuel, it offers increased vehicle power and performance.

D5798-11 Standard Specification for Ethanol Fuel Blends for Flexible-Fuel Automotive Spark-Ignition Engines

Property

ASTM Method

Class 1

Class 2

Class 3

Class 4

Vapor Pressure, psi

D5191

5.5-8.5

7.0-9.5

8.5-12.0

9.5-15.0

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D5798-11 Standard Specification for Ethanol Fuel Blends for Flexible-Fuel Automotive Spark-Ignition Engines

Property

ASTM Method

Class 1

Class 2

Class 3

Ethanol Content, vol%

D5501

51-83

Methanol, vol%

D5501

0.5, maximum

Higher Alcohols, vol%

D5501

2, maximum

Sulfur, ppmw

D5453

80, maximum

Acidity, mass%

D1613

0.005, maximum

Washed gum, mg/100mL

D381

5, maximum

Unwashed gum, mg/100mL

D381

20, maximum

pHe

D6423

6.5-9.0

Inorganic Chloride, ppmw

D7328

1, maximum

Water, mass%

E203

Inorganic Sulfate, ppmw

D7328

No Limit

Potential Sulfate, ppmw

D7328

No Limit

Class 4

1.0, maximum

Biobutanol Biobutanol is a 4-carbon alcohol (butyl alcohol) produced from the same feedstocks as ethanol including corn, sugar beets, and other biomass feedstocks. Butanol is generally used as an industrial solvent in products such as lacquers and enamels, but it also can be blended with other fuels for use in conventional gasoline vehicles. The U.S. Environmental Protection Agency regulations require the use of oxygenates in certain areas of the country during the winter months. Biobutanol can

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be used as an oxygenate and blended with gasoline in concentrations up to 11.5% by volume. Similar to methanol and ethanol, biobutanol blends of 70%-85% or more with gasoline are alternative fuels under the Energy Policy Act of 1992. Production Producing biobutanol via fermentation has been possible since the early 1900s but is currently more expensive than producing petrochemicals. Modern butanol is produced almost entirely from petroleum. Renewed interest in biobutanol as a sustainable vehicle fuel has spurred technological advances to ferment biobutanol. The first commercial-scale plants are expected to be conversions of ethanol corn plants to biobutanol corn plants. Benefits Biobutanol is an alternative to conventional transportation fuels. The benefits of biobutanol include: Higher Energy Content—Biobutanol's energy density is 10% to 20% lower than gasoline's, which makes its energy content relatively high among gasoline alternatives. Increased Energy Security—Biobutanol can be produced domestically from a variety of feedstocks, while creating U.S. jobs. Fewer Emissions—Carbon dioxide captured by growing feedstocks reduces overall greenhouse gas emissions by balancing carbon dioxide released from burning biobutanol. More Flexibility—Biobutanol blends well with gasoline and ethanol, and it can improve blends of gasoline with ethanol. Also, it can be produced using existing ethanol production facilities with few modifications. Butanol is largely compatible with and in some ways better than, gasoline. It's air/fuel mixture (Stoichometric A/F Ratio) is 11.2 (Standard Gasoline is 14.7, ethanol is 9.) which allows butanol to, just about, function in a standard gasoline engine. Its energy content is about 105,000 Btu per US gallon (Standard Gasoline has about 114,000 Btu per US gallon). In effect butanol has about 92% of the energy of gasoline. In

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actual driving conditions, as butanol has a strong power and torque content, drivers will use a lighter foot on the accelerator and hold a higher gear longer, fuel efficiency will approximately match that of gasoline. It can be mixed with gasoline in any ratio in unmodified engines. Additionally, as butanol has a very low vapour pressure point (RVP 0.3) and a high Flash Point (FP 37 degrees Celcius) it is a very safe fuel to use in high temperatures. Butanol can be produced at an estimated cost of 85 cents per gallon, and is a direct replacement for gasoline, which ethanol cannot be. Butanol also has a high cetane number (CN25, diesel averages CN45, ethanol CN9) which allows butanol to be blended with petrodiesel and with vegetable oils (where it also reduces the gel temperature point and the viscosity) to produce biodiesel, with some positive environmental effects. Consequently, butanol is a very versatile fuel and fuel extender in both gasoline and diesel engines. It can do things that ethanol will never be able to do. Its manufacture from biomass will enhance the progress towards a biofuel World. Advantages 

Higher energy content than ethanol.



Not as corrosive as ethanol.



Uses an air/fuel ratio which is close to that of gasoline. Ethanol does not.



Can be shipped through existing fuel pipelines where ethanol must be transported via rail, barge or truck.



Can replace gasoline any percentage up to 100%. Ethanol can only be used up to 85%.



Gives better mileage than ethanol.



Safer to handle than ethanol.



Will also assist in the conversion of vegetable oils into biodiesel.

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Energy Content in Btu/gallon . 64,000

Methanol

. 84,000

Ethanol

105,000

Butanol

114,000

Gasoline

120,000

Biodiesel

130,000

Petrodiesel

Vegetable oil is an alternative fuel for Diesel engines and for heating oil burners. For engines designed to burn diesel fuel, the viscosity of vegetable oil must be lowered to allow for proper atomization of the fuel; otherwise incomplete combustion and carbon build up will ultimately damage the engine. History Rudolf Diesel Rudolf Diesel was the father of the engine which bears his name. His first attempts were to design an engine to run on coal dust, but later designed his engine to run on vegetable oil. The idea, he hoped, would make his engines more attractive to farmers having a source of fuel readily available. In a 1912 presentation to the British Institute of Mechanical Engineers, he cited a number of efforts in this area and remarked, "The fact that fat oils from vegetable sources can be used may seem insignificant today, but such oils may perhaps become in course of time of the same importance as some natural mineral oils and the tar products are now."[1] Periodic petroleum shortages spurred research into vegetable oil as a diesel substitute during the 1930s and 1940s, and again in the 1970s and early 1980s when straight vegetable oil enjoyed its highest level of scientific interest. The 1970s also saw the formation of the first commercial enterprise to allow consumers to run straight vegetable oil in their automobiles, Elsbett of Germany. In the 1990s

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Bougainville conflict, islanders cut off from oil supplies due to a blockade used coconut oil to fuel their vehicles. Academic research into straight vegetable oil fell off sharply in the 1980s with falling petroleum prices and greater interest in biodiesel as an option that did not require extensive vehicle modification. Application and usability Modified fuel systems Most diesel car engines are suitable for the use of straight vegetable oil (SVO), also commonly called pure plant oil (PPO), with suitable modifications. Principally, the viscosity and surface tension of the SVO/PPO must be reduced by preheating it, typically by using waste heat from the engine or electricity, otherwise poor atomization, incomplete combustion and carbonization may result. One common solution is to add a heat exchanger and an additional fuel tank for the petrodiesel or biodiesel blend and to switch between this additional tank and the main tank of SVO/PPO. The engine is started on diesel, switched over to vegetable oil as soon as it is warmed up and switched back to diesel shortly before being switched off to ensure that no vegetable oil remains in the engine or fuel lines when it is started from cold again. In colder climates it is often necessary to heat the vegetable oil fuel lines and tank as it can become very viscous and even solidify. Single tank conversions have been developed, largely in Germany, which have been used throughout Europe. These conversions are designed to provide reliable operation with rapeseed oil that meets the German rapeseed oil fuel standard DIN 51605. Modifications to the engines cold start regime assist combustion on start up and during the engine warm up phase. Suitably modified indirect injection (IDI) engines have proven to be operable with 100% PPO down to temperatures of −10°C. Direct injection (DI) engines generally have to be preheated with a block heater or diesel fired heater. The exception is the VW Tdi (Turbocharged Direct Injection) engine for which a number of German companies offer single tank conversions. For long term durability it has been found necessary to increase the oil change frequency and to pay increased attention to engine maintenance.

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Unmodified indirect injection engines Many cars powered by indirect injection engines supplied by in-line injection pumps, or mechanical Bosch injection pumps are capable of running on pure SVO/PPO in all but winter temperatures. Indirect injection Mercedes-Benz vehicles with in-line injection pumps and cars featuring the PSA XUD engine tend to perform reasonably, especially as the latter is normally equipped with a coolant heated fuel filter. Engine reliability would depend on the condition of the engine. Attention to maintenance of the engine, particularly of the fuel injectors, cooling system and glow plugs will help to provide longevity. Ideally the engine would be converted. Vegetable oil blending The relatively high kinematic viscosity of vegetable oils must be reduced to make them compatible with conventional compression-ignition engines and fuel systems. Cosolvent blending is a low-cost and easy-to-adapt technology that reduces viscosity by diluting the vegetable oil with a low-molecular-weight solvent. This blending, or "cutting", has been done with diesel fuel, kerosene, and gasoline, amongst others; however, opinions vary as to the efficacy of this. Noted problems include higher rates of wear and failure in fuel pumps and piston rings when using blends. Home heating When liquid fuels made from biomass are used for energy purposes other than transport, they are called bioliquids. With often minimal modification, most residential furnaces and boilers that are designed to burn No. 2 heating oil can be made to burn either biodiesel or filtered, preheated waste vegetable oil (WVO). If cleaned at home by the consumer, WVO can result in considerable savings. Many restaurants will receive a minimal amount for their used cooking oil, and processing to biodiesel is fairly simple and inexpensive. Burning filtered WVO directly is somewhat more problematic, since it is much more viscous; nonetheless, its burning can be accomplished with suitable preheating. WVO can thus be an economical heating option for those with the necessary mechanical and experimental aptitude.

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Combined heat and power A number of companies offer compressed ignition engine generators optimized to run on plant oils where the waste engine heat is recovered for heating. Properties The main form of SVO/PPO used in the UK is rapeseed oil (also known as canola oil, primarily in the United States and Canada) which has a freezing point of 10°C.[citation needed] However the use of sunflower oil, which gels at around -12°C, is currently being investigated as a means of improving cold weather starting. Unfortunately oils with lower gelling points tend to be less saturated (leading to a higher iodine number) and polymerize more easily in the presence of atmospheric oxygen. Material compatibility Polymerization also has been consequentially linked to catastrophic component failures such as injection pump shaft seizure and breakage, injector tip failure leading to various and/or combustion chamber components damaged. Most metallurgical problems such as corrosion and electrolysis are related to water based contamination or poor choices of plumbing (such as copper or Zinc) which can cause gelling- even with petroleum based fuels. Temperature effects Some Pacific island nations are using coconut oil as fuel to reduce their expenses and their dependence on imported fuels while helping stabilize the coconut oil market. Coconut oil is only usable where temperatures do not drop below 17 degrees Celsius (62 degrees Fahrenheit), unless two-tank SVO/PPO kits or other tank-heating accessories, etc. are used. Fortunately, the same techniques developed to use, for example, canola and other oils in cold climates can be implemented to make coconut oil usable in temperatures lower than 17 degrees Celsius.

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Availability Recycled vegetable oil Recycled vegetable oil, also termed used vegetable oil (UVO), waste vegetable oil (WVO), used cooking oil, or yellow grease (in commodities exchange), is recovered from businesses and industry that use the oil for cooking. As of 2000, the United States was producing in excess of 11 billion liters (2.9 billion U.S. gallons) of recycled vegetable oil annually, mainly from industrial deep fryers in potato processing plants, snack food factories and fast food restaurants. If all those 11 billion liters could be recycled and used to replace the energy equivalent amount of petroleum (an ideal case), almost 1% of US oil consumption could be offset. Use of used vegetable oil as a direct fuel competes with some other uses of the commodity, which has effects on its price as a fuel and increases its cost as an input to the other uses as well. Virgin vegetable oil Virgin vegetable oil, also termed pure plant oil or straight vegetable oil, is extracted from plants solely for use as fuel. In contrast to used vegetable oil, is not a byproduct of other industries, and thus its prospects for use as fuel are not limited by the capacities of other industries.[citation needed] Production of vegetable oils for use as fuels is theoretically limited only by the agricultural capacity of a given economy. However, doing so detracts from the supply of other uses of pure vegetable oil. Legal implications Taxation of fuel Taxation on SVO/PPO as a road fuel varies from country to country, and it is possible the revenue departments in many countries are even unaware of its use, or feel it too insignificant to legislate. Germany used to have 0% taxation, resulting in it being a leader in most developments of the fuel use. However SVO/PPO as a road fuel began to be taxed at 0,09 €/liter from 1 January 2008 in Germany, with incremental rises up to 0,45 €/liter by 2012. However, in Australia it has become illegal to produce any fuel if it is to be sold unless a license to do so is granted by the

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federal government. This is a chargeable offense with a fine of up to 20,000 dollars but this bracket may alter circumstantially. Also a jail term may result if offenders are aware of the illegality of selling the fuel. BIODESIEL Biodiesel Fuel Basics Biodiesel is a domestically produced, renewable fuel that can be manufactured from vegetable oils, animal fats, or recycled restaurant grease. It is a cleaner-burning replacement for petroleum diesel fuel. It is nontoxic and biodegradable. Biodiesel is a liquid fuel often referred to as B100 or neat biodiesel in its pure, unblended form. Like petroleum diesel, biodiesel is used to fuel compression-ignition engines, which run on petroleum diesel. See the table for biodiesel's physical characteristics. How well biodiesel performs in cold weather depends on the blend of biodiesel. The smaller the percentage of biodiesel in the blend, the better it performs in cold temperatures. Regular No. 2 diesel and B5 perform about the same in cold weather. Both biodiesel and No. 2 diesel have some compounds that crystallize in very cold temperatures. In winter weather, manufacturers combat crystallization in No. 2 diesel by adding a cold flow improver. For the best cold weather performance, drivers should use B20 made with No. 2 diesel manufactured for cold weather.

Biodiesel's Physical Characteristics

Specific gravity

0.88

Kinematic viscosity at 40°C

4.0 to 6.0

Cetane number

48 to 65

Higher heating value, Btu/gal

127,042

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Lower heating value, Btu/gal

118,170

Density, lb/gal at 15.5°C

7.3

Carbon, wt%

77

Hydrogen, wt%

12

Oxygen, by dif. wt%

11

Boiling point, °C

315-350

Flash point, °C

100-170

Sulfur, wt%

0.0 to 0.0024

Cloud point, °C

-3 to 15

Pour point, °C

-5 to 10

Biodiesel Blends Biodiesel can be blended and used in many different concentrations, including B100 (pure biodiesel), B20 (20% biodiesel, 80% petroleum diesel), B5 (5% biodiesel, 95% petroleum diesel) and B2 (2% biodiesel, 98% petroleum diesel). B20 is a common biodiesel blend in the United States. Low-Level Blends ASTM International develops specifications for conventional diesel fuel (ASTM D975). These specifications allow for biodiesel concentrations of up to 5% (B5). Lowlevel biodiesel blends, such as B5 are ASTM approved for safe operation in any compression-ignition engine designed to be operated on petroleum diesel. This can include light-duty and heavy-duty diesel cars and trucks, tractors, boats, and electrical generators.

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B20 B20 (20% biodiesel, 80% petroleum diesel) is the most common biodiesel blend in the United States. B20 is popular because it represents a good balance of cost, emissions, cold-weather performance, materials compatibility, and ability to act as a solvent. Using B20 provides substantial benefits and avoids many of the coldweather performance and material compatibility concerns associated with B100. Most biodiesel users purchase B20 or lower blends from their petroleum distributors or biodiesel marketers. Biodiesel blends of 20% (B20) or higher qualify for biodiesel fuel use credits under the Energy Policy Act of 1992. B20 and lower-level blends generally do not require engine modifications. Engines operating on B20 have similar fuel consumption, horsepower, and torque to engines running on petroleum diesel. B20 has a higher cetane number (a measure of the ignition value of diesel fuel) and higher lubricity (the ability to lubricate fuel pumps and fuel injectors) than petroleum diesel. However, not all diesel engine manufacturers cover biodiesel use in their warranties (see the National Biodiesel Board's OEM Information for those that do support the use of biodiesel blends). Because diesel engines are expensive, users should consult their vehicle and engine warranty statements before using biodiesel. Biodiesel blends between B6 and B20 must meet prescribed quality standards— ASTM D7467 (summary of requirements). B100, or neat biodiesel, contains about 8% less energy per gallon than petroleum diesel. For B20, this could mean a 1% to 2% difference, but most B20 users report no noticeable difference in performance or fuel economy. Biodiesel has some emissions benefits, especially for engines manufactured before 2010. For engines equipped with selective catalytic reduction (SCR) systems, the air quality benefits are the same whether running on biodiesel or petroleum diesel. However, biodiesel still offers better greenhouse gas (GHG) benefits compared to conventional diesel fuel. The emissions benefit is roughly commensurate with the blend level; that is, B20 would have 20% of the GHG reduction benefit of B100.

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B100 B100 and other high-level biodiesel blends are less common than B5 or B20 due to a lack of regulatory incentives and pricing. B100 can be used in some engines built since 1994 with biodiesel-compatible material for parts, such as hoses and gaskets. B100 has a solvent effect and it can clean a vehicle's fuel system and release deposits accumulated from previous petroleum diesel use. The release of these deposits may initially clog filters and require filter replacement in the first few tanks of high-level blends. When using high-level blends, a number of issues can come into play. The higher the percentage of biodiesel above 20%, the lower the energy content per gallon. High-level biodiesel blends can also impact engine warranties, gel in cold temperatures, and suffer from microbial contamination in tanks. B100 use could also increase nitrogen oxides emissions, although it greatly reduces other toxic emissions. B100 requires special handling and may require equipment modifications. To avoid engine operational problems, B100 must meet the requirements of ASTM D6751, Standard Specification for Biodiesel Fuel (B100) Blend Stock for Distillate Fuels (summary of requirements). ASTM Specification D6751 now includes a No.1-B and a No.2-B grade. The No.1-B grade has stricter limits on monoglycerides and filterability than the No.2-B grade. The No.1-B grade is a special purpose biodiesel grade for use in applications where low temperature operability is needed. Biodiesel Production and Distribution Biodiesel is a legally registered fuel and fuel additive with the U.S. Environmental Protection Agency (EPA). EPA registration includes all biodiesel that meets ASTM D6751 and is feedstock neutral. The federal Renewable Fuel Standard requires at least 1 billion gallons of biomass-based diesel consumption in the U.S. (at this time, biodiesel comprises the vast majority of biomass-based diesel in the US). The RFS requires 1.3 billion gallons of biomass-based diesel in 2013.

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Production Biodiesel is produced from vegetable oils, yellow grease, used cooking oils, and tallow. The production process converts oils and fats into chemicals called longchain mono alkyl esters, or biodiesel. These chemicals are also referred to as fatty acid methyl esters, and the process is referred to as transesterification. Roughly speaking, 100 pounds of oil or fat are reacted with 10 pounds of a short-chain alcohol (usually methanol) in the presence of a catalyst (usually sodium hydroxide [NaOH] or rarely, potassium hydroxide [KOH]) to form 100 pounds of biodiesel and 10 pounds of glycerin. Glycerin, which is used in pharmaceuticals and cosmetics, among other markets, is a co-product. Although the process is relatively simple, homemade biodiesel is not recommended. Diesel engines are expensive and risking damage, loss of warranty, and operational problems from fuel that does not meet rigorous ASTM D6751 specifications is not wise. Production Path Raw or refined plant oil, or recycled greases that have not been processed into biodiesel, are not biodiesel and should be avoided. Fats and oils (triglycerides) are much more viscous than biodiesel, and low-level vegetable oil blends can cause long-term engine deposits, ring sticking, lube-oil gelling, and other maintenance problems that can reduce engine life. Research is currently focused on developing algae as a potential biodiesel feedstock, because it's expected to produce high yields from a smaller area of land than vegetable oils.

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Advantages and Disadvantages Of Biodiesel Fuel Compared to other alternative fuels, biodiesel fuel supports some unique features and qualities. Unlike any other alternative fuels, it has successfully passed all the health effects testing requirements, meeting the standards of the 1990 Clean Air Act Amendments. Here in this article, we will shed light on both the advantages and disadvantages of biodiesel fuels. Read on to know more. Advantages of biodiesel fuel •

Biodiesel fuel is a renewable energy source unlike petroleum-based diesel.

•

An excessive production of soybeans in the world makes it an economic way

to utilize this surplus for manufacturing the Biodiesel fuel. •

One of the main biodiesel fuel advantages is that it is less polluting than

petroleum diesel. •

The lack of sulfur in 100% biodiesel extends the life of catalytic converters.

•

Another of the advantages of biodiesel fuel is that it can also be blended with

other energy resources and oil. •

Biodiesel fuel can also be used in existing oil heating systems and diesel

engines without making any alterations. •

It can also be distributed through existing diesel fuel pumps, which is another

biodiesel fuel advantage over other alternative fuels. •

The lubricating property of the biodiesel may lengthen the lifetime of engines.

Disadvantages of biodiesel fuel •

At present, Biodiesel fuel is bout one and a half times more expensive than

petroleum diesel fuel. •

It requires energy to produce biodiesel fuel from soy crops, plaus there is the

energy of sowing, fertilizing and harvesting. •

Another biodiesel fuel disadvantage is that it can harm rubber hoses in some

engines.

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As Biodiesel cleans the dirt from the engine, this dirt can then get collected in

the fuel filter, thus clogging it. So, filters have to be changed after the first several hours of biodiesel use. •

Biodiesel fuel distribution infrastructure needs improvement, which is another

of the biodiesel fuel disadvantages.

What are the benefits / disadvantages of running straight vegetable oil Benefits of vegetable oil run vehicles: 

CO2 neutral



Economical, cheaper than diesel



Excellent system-energy efficiency (from raw "crude" to refined product) Sulphur-free



Protects crude oil resources



100% biodegradable



Non-hazardous for ground, water, and air in case of a spill



Low fire hazard (flashpoint > 220°C)



Practical to refuel at home



Easy to store, more ecological than bio-diesel



A chance for the farming community and agriculture

Disadvantages of vegetable oil run vehicles: 

Loss of space and/or vehicle load capacity due to additional fuel storage



Loss of manufacturer guarantee in new vehicles for use of an alternative fuel



Motor oil needs to be replaced more often in a direct injection engine as a safety precaution to avoid build-up



Currently no public network of filling stations are available, must refuel at home

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What are biobutanol advantages? One of the most important biobutanol advantage is the fact that its will reduce carbon emissions.

The EPA has released data showing that hydrocarbon, carbon

monoxide, and nitrogen oxide releases can be greatly reduced by use of biobutanol. Another advantage is that biobutanol has a higher energy content than ethanol, almost 20% more by density. Due to its similarities to conventional gasoline, it is able to blend much better than ethanol with gasoline. It has even shown promise when using 100% biobutanol in a conventional gasoline engine. Besides these, biobutanol experiences a lower chance of separation and corrosion than ethanol. Biobutanol also resists water absorption, allowing it to be transported in pipes and carriers used by gasoline. A very exciting advantage of biobutanol is that vehicles require no modifications to use it. This means that with effective pumping systems, it can be implemented immediately. Currently, funds are quickly rising for biobutanol production and the only requirement is a cheap and fast modification to the ethanol plants which already exist.

As yield efficiencies rise, the cost of biobutanol will

continue to drop from its already reasonable price. DISADVANTAGES Compared to oil, it is uneconomical, and too expensive to refine, hence the fact it hasn't been properly commercialized in large scale situations, despite its unique qualities. ADVANTAGES AND DISADVANGES OF ETHANOL Advantages o o

Unlike petroleum, ethanol is a

o

Ethanol has a lower heat of

renewable resource

combustion (per mole, per unit of

Ethanol burns more cleanly in air

volume, and per unit of mass) that

than petroleum, producing less

petroleum

carbon (soot) and carbon monoxide o

Disadvantages

o

Large amounts of arable land are

The use of ethanol as opposed to

required to produce the crops

petroleum could reduce carbon

required to obtain ethanol, leading

dioxide emissions, provided that a

to problems such as soil erosion,

renewable energy resource was

deforestation, fertiliser run-off and

used to produce crops required to

salinity

obtain ethanol and to distil

o

Major environmental problems would arise out of the disposal of waste

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fermented ethanol

fermentation liquors. o

Typical current engines would require modification to use high concentrations of ethanol

Methanol, a Potentially Renewable Energy Resource Advantages and drawbacks The advantages of M85 include: 

Methanol has the potential to provide a bridge to the hydrogen economy of the future. Methanol can be used to produce hydrogen, and the methanol industry is working on technologies that would allow methanol to produce hydrogen for fuel cells.



M85 has a high octane rating of 102, higher than E85 (Ethanol) at 96, or gasoline at 86-94.



M85 can be produced in the US. This will improve energy security by reducing the reliance on imported oil.



There are significant health and environmental benefits associated with the use of M85.



M85 can be dispensed from pumps much the same as gasoline.



Because of its high flash point, pure methanol (M100) is less volatile than gasoline. It burns more slowly and at a lower temperature.

The drawbacks of M85 include: 

Fuel storage tanks and dispensing equipment must be corrosion and damage resistant. This is because of the potentially harmful nature of M85 (in the case of spills/leaks), and the fact that it is a corrosive solvent. Fuel delivery requires use of non-corroding hoses and stainless steel fuel tanks.



Although the refueling process is the same as that for gasoline, there is little or no retail refueling available in the US.

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

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Methanol has about half the energy content of gasoline. Because mileage using M85 is lower than mileage using gasoline (10-20%), refueling is needed more frequently.



M85 can be more expensive than gasoline.



M85 is a volatile fuel (flammable) because of the blending with gasoline.



As with gasoline and ethanol, methanol can be fatal when ingested. Inhalation of fumes and direct contact with skin can also be harmful.

ADVANTAGES AND DISADVATAGES OF BIOFUEL Advantages and Benefits of Biogas 

Provides a non-polluting and renewable source of energy.



Efficient way of energy conversion (saves fuelwood).



Saves women and children from drudgery of collection and carrying of firewood, exposure to smoke in the kitchen, and time consumed for cooking and cleaning of utensils.



Produces enriched organic manure, which can supplement or even replace chemical fertilizers.



Leads to improvement in the environment, and sanitation and hygiene.



Provides a source for decentralized power generation.



Leads to employment generation in the rural areas.



Household wastes and bio-wastes can be disposed of usefully and in a healthy manner.



The technology is cheaper and much simpler than those for other bio-fuels, and it is ideal for small scale application.



Dilute waste materials (2-10% solids) can be used as in feed materials.



Any biodegradable matter can be used as substrate.



Anaerobic digestion inactivates pathogens and parasites, and is quite effective in reducing the incidence of water borne diseases.



Environmental benefits on a global scale: Biogas plants significantly lower the greenhouse effects on the earth’s atmosphere. The plants lower methane emissions by entrapping the harmful gas and using it as fuel.

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Disadvantages of Biogas 

The process is not very attractive economically (as compared to other biofuels) on a large industrial scale.



It is very difficult to enhance the efficiency of biogas systems.



Biogas contains some gases as impurities, which are corrosive to the metal parts of internal combustion engines.



Not feasible to locate at all the locations.

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CHAPTER 7 ELECTRIC VEHICLES INTRODUCTION An electric vehicle (EV), also referred to as an electric drive vehicle, uses one or more electric motors or traction motors for propulsion. Three main types of electric vehicles exist, those that are directly powered from an external power station, those that are powered by stored electricity originally from an external power source, and those that are powered by an on-board electrical generator, such as an internal combustion engine (hybrid electric vehicles) or a hydrogen fuel cell.[3] EVs include plug-in electric cars, hybrid electric cars, hydrogen vehicles, electric trains, electric lorries, electric airplanes, electric boats, electric motorcycles and scooters and electric spacecraft.[4] Diesel submarines operating on battery power are, for the duration of the battery run, electric submarines, and some of the lighter UAVs are electrically-powered. Proposals exist for electric tanks. EVs first came into existence in the mid-19th century, when electricity was among the preferred methods for motor vehicle propulsion, providing a level of comfort and ease of operation that could not be achieved by the gasoline cars of the time. The internal combustion engine (ICE) has been the dominant propulsion method for motor vehicles for almost 100 years, but electric power has remained commonplace in other vehicle types, such as trains and smaller vehicles of all types. During the last few decades, environmental impact of the petroleum-based transportation infrastructure, along with the peak oil, has led to renewed interest in an electric transportation infrastructure. EVs differ from fossil fuel-powered vehicles in that the electricity they consume can be generated from a wide range of sources, including fossil fuels, nuclear power, and renewable sources such as tidal power, solar power, and wind power or any combination of those. The carbon footprint and other emissions of electric vehicles varies depending on the fuel and technology used for electricity generation. The electricity may then be stored on board the vehicle using a battery, flywheel, or supercapacitors. Vehicles making use of engines working on the principle of combustion can usually only derive their energy from a

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single or a few sources, usually non-renewable fossil fuels. A key advantage of hybrid or plug-in electric vehicles is regenerative braking due to their capability to recover energy normally lost during braking as electricity is stored in the on-board battery. ELECTRIC VEHICLE COMPONENTS Electric Motor Every electric car needs a motor. Electric motors vary in shape and size, weight and price. They can use AC or DC electricity. A budget builder may choose to use an electric motor from an old forklift or elevator system. There are also lots of electric car-specific motors available for purchase alone or as part of a kit. You will need to choose a motor that will suit your needs for performance and budget. Motor Controller The purpose of the motor controller is to adjust the speed at which the motor spins. If 120V were applied directly to an electric motor for example, it would run at full speed. There needs to be a means of adjusting the output of the motor and this is precisely what the motor controller is for. It allows the motor to run at any speed between zero rpm and its max rpm. This part can also be salvaged either from a forklift or golf cart. Throttle Pot Box A pot box is a small part that connects to your stock throttle cable. When you push on your throttle, the pot box sends a signal corresponding to the amount of pressure you’re putting on the pedal to the controller which then sends the proper power to the motor.

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Adapter Plate The adapter plate mates the electric motor to a stock transmission. These can be bought for any commonly converted vehicle. Most EV-specific motors have a standard bolt pattern so most adapter plates will work with most motors. If you use a motor from a forklift you will need to have an adapter plate custom built or of course if you’re a decent fabricator you can always do this yourself. Contactor This is basically a high-voltage relay. It connects your battery pack to the controller when you turn on the key. Fuse A fuse will blow and cut power when too much amperage is drawn. Manual Switch There needs to be one (or more) manual disconnects for the main battery pack. This way if all else fails you can manually disconnect the power and safely stop the vehicle. Batteries There are many different types of batteries available. The type of batteries that you choose will affect your performance and range. Charger There are many different types of chargers available and the charger you need will depend on the batteries you use.

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DC/DC Converter The DC/DC converter takes the voltage of your main (traction) battery pack and reduces it to 12V which keeps your 12V battery charged. An electric vehicle still needs an 12V battery to power all the lights, stereo, horn etc. Keeping this battery charged can be achieved other ways as well. Some EV builders use an alternator that runs off the electric motor and others use a separate 12V charger to charge this battery. Gauges You will need to know what’s going on under the hood and this is where your gauges come in. Most basic EV builds use a high-voltage ammeter and voltage gauge (for traction pack voltage) and a low voltage gauge (12V system). Heater Although a heater is not necessary to drive the car, it is a creature comfort that we have all become accustomed to. Being that the stock heater in any gasoline car uses heat created by the gasoline engine to heat the cabin, we need to figure out something else to get heat into the vehicle. There are several ways to do this. Ceramic Element - This is the most common means of heating an EV. A ceramic element is placed within the heater core or otherwise inside the heater box and powered with the traction pack voltage. The ceramic element basically becomes the heater core and other than a switch required to turn the element on, the system will function as normal.

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Fluid Heater - A fluid heater uses the stock heater core and circulates fluid through it just like the stock system would. The fluid is heated by an electric element and circulated through the heater core by a small pump.

Space Heater - It is possible to use a small ceramic space heater in the car with an AC power inverter. AC inverters however are quite expensive and this is not typically a cost effective way of heating an EV. Heated Seats - Heated seat covers are widely available nowadays and put out a good amount of heat. The air in the car will stay cold but a heated seat can do wonders to make you feel warm. Heat the Car Prior To Use - Simply put a space heater in the car for a while prior to use. It will heat the car and stay warm long enough for a short commute.

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WORKING OF BATTERY ELECTRIC VEHICLE ELECTRIC BATTERY A battery is a device for storing chemical energy and converting that chemical energy into electricity. A battery is made up of one or more electrochemical cells, each of which consists of two half-cells or electrodes. One half-cell, called the negative electrode, has an overabundance of the tiny, negatively charged subatomic particles called electrons. The other, called the positive electrode, has a

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deficit of electrons. When the two halves are connected by a wire or an electrical cable, electrons will flow from the negative electrode to the positive electrode. We call this flow of electrons electricity. The energy of these moving electrons can be harnessed to do work -- running a motor, for instance. As electrons pass to the positive side, the flow gradually slows down and the voltage of the electricity produced by the battery drops. Eventually, when there are as many electrons on the positive side as on the negative side, the battery is considered 'dead' and is no longer capable of producing an electric flow.

Lead-acid batteries, similar to the one shown here, have been used in automobiles since the middle of the 19th century.

The electrons are generated by chemical reactions, and there are many different chemical reactions that are used in commercially available batteries. For example, the familiar alkaline batteries commonly used in flashlights and television remote controls generate electricity through a chemical reaction involving zinc and manganese oxide. Most alkaline batteries are considered to be a disposable battery. Once they go dead, they're useless and should be recycled. Automobile batteries, on the other hand, need to be rechargeable, so they don't require constant replacement. In a rechargeable battery, electrical energy is used to reverse the negative and positive halves of the electrochemical cells, restarting the electron flow.

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Automobile manufacturers have identified three types of rechargeable battery as suitable for electric car use. Those types are lead-acid batteries, nickel metal hydride (NiMH) batteries, and lithium-ion (Li-ion) batteries. Lead-acid batteries were invented in 1859 and are the oldest form of rechargeable battery still in use. They've been used in all types of cars -- including electric cars -since the 19th century. Lead-acid batteries are a kind of wet cell battery and usually contain a mild solution of sulfuric acid in an open container. The name comes from the combination of lead electrodes and acid used to generate electricity in these batteries. The major advantage of lead-acid batteries is that, after having been used for so many years, they are well understood and cheap to produce. However, they do produce dangerous gases while being used and if the battery is overcharged there's a risk of explosion. Nickel metal hydride batteries came into commercial use in the late 1980s. They have a high energy density -- that is, a great deal of energy can be packed into a relatively small battery -- and don't contain any toxic metals, so they're easy to recycle.

This 2007 Chevy Volt concept vehicle chassis clearly shows the location of the vehicle's lithium-ion battery pack (in blue).

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Lithium-ion batteries, which came into commercial use in the early 1990s, have a very high energy density and are less likely than most batteries to lose their charge when not being used -- a property called self discharge. Because of their light weight and low maintenance requirements, lithium-ion batteries are widely used in electronic devices such as laptop computers. Some experts believe that lithium-ion batteries are about as close as science has yet come to developing a perfect rechargeable battery, and this type of battery is the best candidate for powering the electric cars of the near future. A variation on lithium-ion batteries, called lithium-ion polymer batteries, may also prove valuable to the future of EVs. These batteries may eventually cost less to build than lithium-ion batteries; however, at the present time, lithium-ion polymer batteries are prohibitively expensive.

What is an EV charger? An electric vehicle charger is responsible for recharging the battery banks in an electric vehicle or a plug-in hybrid vehicle. EV chargers are installed in your house, office, shopping stores, and public places to enable one to charge their electric cars or plug-in hybrids. One needs more than 1 EV charger per vehicle as the driving distance between charges is limited and one would need to charge their electric vehicle before getting back home. How are EV Chargers or car charging stations classified?

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Level 1 – Plugs in to 110 V / NEMA 5-20

Level 2 – Plugs in to 208-240 V (220 V nominal) / J1772

Level 3 – Plugs in to 440 V DC / Chademo

The higher the level, the quicker the vehicle charges. The Level 1 and Level 2 chargers are typical for home use. Level 2 charging stations will be found at retail stores, restaurants, and malls. Level 3 are close to being commercial & more broadly available. They are being targeted for quick charge at various parking facilities and retail locations. EV Drives Electric cars can use AC or DC motors: 

If the motor is a DC motor, then it may run on anything from 96 to 192 volts. Many of the DC motors used in electric cars come from the electric forklift industry.



If it is an AC motor, then it probably is a three-phase AC motor running at 240 volts AC with a 300 volt battery pack.

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DC installations tend to be simpler and less expensive. A typical motor will be in the 20,000-watt to 30,000-watt range. A typical controller will be in the 40,000-watt to 60,000-watt range (for example, a 96-volt controller will deliver a maximum of 400 or 600 amps). DC motors have the nice feature that you can overdrive them (up to a factor of 10-to-1) for short periods of time. That is, a 20,000-watt motor will accept 100,000 watts for a short period of time and deliver 5 times its rated horsepower. This is great for short bursts of acceleration. The only limitation is heat build-up in the motor. Too much overdriving and the motor heats up to the point where it selfdestructs. AC installations allow the use of almost any industrial three-phase AC motor, and that can make finding a motor with a specific size, shape or power rating easier. AC motors and controllers often have a region feature. During braking, the motor turns into a generator and delivers power back to the batteries. Right now, the weak link in any electric car is the batteries. There are at least six significant problems with current lead-acid battery technology: 

They are heavy (a typical lead-acid battery pack weighs 1,000 pounds or more).



They are bulky (the car we are examining here has 50 lead-acid batteries, each measuring roughly 6" x 8" by 6").



They have a limited capacity (a typical lead-acid battery pack might hold 12 to 15 kilowatt-hours of electricity, giving a car a range of only 50 miles or so).



They are slow to charge (typical recharge times for a lead-acid pack range between four to 10 hours for full charge, depending on the battery technology and the charger).



They have a short life (three to four years, perhaps 200 full charge/discharge cycles).



They are expensive (perhaps $2,000 for the battery pack shown in the sample car).

ELECTRIC VEHICLES TRANSMISSION

Hybrid vehicle transmissions utilize the electric motor to bridge the torque gap present during synchronisation; this is not possible for all shift scenarios due to

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limiting factors of the electric motor. Zero shift caters for these torque gaps that electric motors are unable to fill. Hybrid vehicle transmission efficiency is an important factor contributing to reduction in fuel consumption and emissions. Electric vehicle transmission (EV transmission) efficiency contributes to improved performance, range and battery life. Zeroshift is currently running a number of programmes integrating Zeroshift technology into various hybrid architectures and power classes. Zeroshift technology can be applied to hybrid and electric vehicle transmission (EV transmission) applications in the following sectors and more... •Cars and motorcycles •LGV's, commercial vehicles, buses •Agricultural vehicles TESLA ELECTRIC TRANSMISSION Starting in September 2008 Tesla Motors selected BorgWarner to manufacture gearboxes and began equipping all Roadsters with a single speed, fixed gear gearbox (8.2752:1) with an electrically actuated parking pawl mechanism and a mechanical lubrication pump. The company previously worked with several companies, including XTrac and Magna International, to find the right automatic transmission, but a two-gear solution proved to be too challenging. This led to substantial delays in production. At the "Town Hall Meeting" with owners in December 2007, Tesla announced plans to ship the initial 2008 Roadsters with their interim Magna two-speed direct shift manual locked into second gear, limiting the performance of the car to less than what was originally stated (0 to 60 mph (0 to 97 km/h) in 5.7 seconds instead of the announced 4.0 seconds). Tesla also announced it would upgrade those transmissions under warranty when the final transmission became available. At the "Town Hall Meeting" with owners on January 30, 2008, Tesla Motors described the planned transmission upgrade as a single-speed gearbox with a drive ratio of 8.27:1

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combined with improved electronics and motor cooling that retain the acceleration from 0 to 60 mph (0 to 97 km/h) in under 4 seconds and an improved motor limit of 14,000 rpm to retain the 125 mph (201 km/h) top speed. The upgraded system also improved the maximum torque from 200 to 280 lb·ft (270 to 380 N·m) and improves the Roadster's quarter mile times.

Electric Vehicles MOTOR DESIGN 

The power requirement (rated power) for acceleration performance (acceleration time and acceleration distance) decreases as constant power region ratio increases.



Conversely, the torque requirement (rated torque) for acceleration increases as constant power region ratio increases. This results in a larger motor size and volume.

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

Passing

performance

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(passing

time

and

passing

distance)

suffers

considerably as the constant power region ratio increases. 

A motor’s maximum speed has a pronounced effect on the required torque of the motor. Low speed motors with the extended constant power speed range have a much higher rated shaft torque. Consequently, they need more iron and copper to support this higher flux and torque.



As motor power decreases (due to extending the range of constant power operation), the required torque is increasing. Therefore, although the converter power requirement (hence the converter cost) will decrease when increasing the constant power range, the motor size, volume, and cost will increase.



Increasing the maximum speed of the motor can reduce the motor size by allowing gearing to increase shaft torque. However, the motor maximum speed cannot be increased indefinitely without incurring more cost and transmission requirements.

Requirements of EVs on Electric Motor Drives 

High instant power and high power density.



High torque at low speeds for starting and climbing, as well as high power at high speed for cruising.



Very wide speed range including constant-torque and constant-power regions.



Fast torque response.



High efficiency over wide speed and torque ranges.



High efficiency for regenerative braking.



High reliability and robustness for various vehicle-operating conditions.



Downsizing, weight reduction, and lower moment of inertia.



Fault tolerance



Reasonable cost



Suppression of electromagnetic interface (EMI) of motor controllers

Major Considerations in design

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The Type of frame structure 

Ventilation



The bearing and shaft



The Magnetic core dimensions & the winding

Design details required: 

The main dimensions of the stator.



Details of stator windings.



Design details of rotor and its windings



Performance characteristics.

Specifications: 

Number of phases



Frequency



Rated output in kW



Type of duty



Voltage connections



Temperature rise



Speed



Pullout torque



Starting torque



Starting current



Power factor



Efficiency/losses



Class of insulation

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Power Systems for Electric Vehicles (Motors and Controllers) The power system of an electric vehicle consists of just two components: the motor that provides the power and the controller that controls the application of that power. In comparison, the power system of gasoline-powered vehicles consists of many components, such as the engine, carburetor, oil pump, water pump, cooling system, starter, and exhaust system. Motors Electric motors convert electrical energy into mechanical energy. Electric vehicles use two types of electric motors to provide power to the wheels: the direct current (dc) motor and the alternating current (ac) motor. DC electric motors have three main components: 

A set of coils (field) that creates the magnetic forces that provide torque



A rotor or armature mounted on bearings that turns inside the field



Commutating device that reverses the magnetic forces and makes the armature turn, thereby providing horsepower.

As in the dc motor, an ac motor also has a set of coils (field) and a rotor or armature; however, since there is a continuous current reversal, a commutating device is not needed. Both types of electric motors are used in electric vehicles and have advantages and disadvantages. While the ac motor is less expensive and lighter in weight, the dc motor has a simpler controller, which lowers the cost of the dc motor/controller combination. The main disadvantage of the ac motor is the cost of the electronics package needed to convert (invert) dc from the battery into ac for the motor. Past electric vehicles used a dc motor/controller system because they operate off the battery current without complex electronics. The dc motor/controller system is still used today on some electric vehicles to keep the cost down. However, with the advent of better and less expensive electronics, a large number of today's electric vehicles are using ac motor/controller systems because of their improved motor

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efficiency and lighter weight. These ac motors resemble motors commonly used in home appliances and machine tools, and they are relatively inexpensive and robust. These motors are very reliable, and since they have only one moving part, the shaft, they should last the life of the vehicle with little or no maintenance. AC Motor

DC Motor

Single-speed transmission

Multispeed transmission

Light weight

Heavier for same power

Less expensive

More expensive

95% efficiency at full load

85-95% efficiency at full load

More expensive controller

Simple controller

Motor/controller/inverter more expensive Motor/controller less expensive Electric Motor Comparison Controllers The electric vehicle controller is the electronics package that operates between the batteries and the motor to control the electric vehicle's speed and acceleration, much like a carburetor does in a gasoline-powered vehicle. The controller transforms dc from the battery current into ac (for ac motors) and regulates the energy flow from the battery. Unlike the carburetor, the controller will also reverse the motor rotation (so the vehicle can go in reverse) and convert the motor into a generator (so that the kinetic energy of motion can be used to recharge the battery when the brake is applied).

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In the early electric vehicles with dc motors, a simple variable-resistor-type controller controlled the acceleration and speed of the vehicle. With this type of controller, full current and power were drawn from the battery all the time. At slow speeds, when full power was not needed, a high resistance was used to reduce the current to the motor. With this type of system, a large percentage of the energy from the battery was wasted as an energy loss in the resistor. The only time that all of the available power was used was at high speeds. Modern controllers adjust speed and acceleration by an electronic process called pulse width modulation. Switching devices, such as silicon-controlled rectifiers, rapidly interrupt (turn on and turn off) the electricity flow to the motor. High power (high speed and/or acceleration) is achieved when the intervals (when the current is turned off) are short. Low power (low speed and/or acceleration) occurs when the intervals are longer. The controllers on most vehicles also have a system for regenerative braking. Regenerative braking is a process by which the motor is used as a generator to recharge the batteries when the vehicle is slowing down. During regenerative braking, some of the kinetic energy normally absorbed by the brakes and turned into heat is converted to electricity by the motor/controller and is used to re-charge the batteries. Regenerative braking not only increases the range of an electric vehicle by 0-5%, it also decreases brake wear and reduces maintenance cost.

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ADVANTAGES AND DISADVANTAGES Advantages 

The number one advantage of an electric vehicle is that no gas is required. One example is the Chevy Volt. It has a battery range of 40 miles. That means it can drive for 40 miles without using gas. 40 miles is more than the range of an average commute to work, so you can go to and from work using no gas. With minimal gas usage comes great savings. You do need gas in the Volt in case your battery runs out or you go for a long distance. However, the amount of fill ups per year will be much fewer with an electric vehicle



You can plug the car into any outlet of the proper voltage and charge the car. Electricity is much cheaper than gas, and the savings will be dramatic



Electric cars give off no emissions. Electric cars are even better than hybrids in this regard. Hybrids running on gas give off emissions, while electric cars are totally 100 percent free of pollutants



Safety is a big concern with these vehicles. However, the fluid batteries actually take impact better than a fully made gas car, and can help even more in the event of an accident

Disadvantages 

The first disadvantage is price. Electric car batteries are not cheap, and the better the battery, the more you will pay. For example, the Chevy Volt has a 40 mile range and sells for around $30,000. Compare that to the 250 to 300 mile range of cars made by Tesla Motors, which sell for anywhere between $50,000 and $100,000



Even though it is a quiet ride, silence can be seen as a disadvantage. People like to hear cars when they are coming up behind them or beside them, and you can't hear if an electric car is near you. This has been known to lead to accidents



Most cars take a long time to recharge their batteries. Tesla Motors' Model S can recharge in 45 minutes, but most electric cars right now take hours to

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charge. You can't drive the car while the batteries are charging usually, so your car will be out of commission while it is plugged in 

Most electric cars currently on the road do not have long ranges. Although in the future it will improve, most of the cars have a range of less than 25 miles, and you can't truly see the great benefits until you ride in a vehicle with a longer range

ELECRTIC VEHCILE PERFORMANCE

Hybrid Electric Vehicles

Some hybrid electric vehicles (HEVs) combine a conventional internal combustion engine (using gasoline, diesel, natural gas, ethanol, or other fuel) with the battery and electric propulsion motor of an electric vehicle. Other hybrids combine a fuel cell with batteries to power electric propulsion motors.

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Hybrids are generally designed as either series or parallel hybrids, depending on how the internal combustion engine (ICE) is used. In the series mode, the engine drives a generator that charges the batteries and provides electricity to the electric motor, which turns the wheels either with or without a transmission. In the parallel mode, the ICE or the electric motor, or both, turn the wheels. The ICE also charges the battery. If an HEV has a fuel cell, the electricity generated by the fuel cell can be used to charge the batteries and power the electric motor, which turns the wheels. Hybrid vehicles combine the range and rapid refueling that consumers expect from a conventional ICE vehicle with some of the energy savings and environmental benefits of an electric vehicle. The practical benefits of HEVs include improved fuel economy and lower emissions compared with conventional ICE vehicles.

Hydrogen fuel cells generate electric power by combining hydrogen and oxygen in an electrochemical device that operates without combustion, so they are pollution free, and the only by-products are water and heat. Fuel cells that use other fuels can have additional by-products such as carbon dioxide and carbon monoxide. Since hydrogen fuel is converted directly to electricity, a fuel cell can operate at much higher efficiencies than ICEs, extracting more energy from the same amount of

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fuel. The fuel cell itself has no moving parts, making it a quiet and reliable source of power. Fuel cells produce dc voltage that can be used to power motors and lights, and charge batteries. Originally developed in the 1800s, fuel cells have been used in the U.S. space program since the 1950s and have the potential to replace ICEs in many applications.

The Advanced Vehicle Testing Activity has performed initial Pomona Loop testing on the Honda Insight and Toyota Prius HEVs. These tests are used to refine the HEVAmerica Baseline Performance testing procedures. Several HEV models have entered Baseline Performance, Accelerated Reliability, and Fleet testing, and the results have been reported since 2001. HEVs require their own test procedures because of their various operating scenarios. For instance, should HEVs be tested in pure electric modes, combined modes, or only in drive cycles when ICEs provide energy and power? HEVAmerica testing procedures have been developed that incorporate these and other operating scenarios. Testing changes include testing HEVs when they are operated in the rechargeable energy storage system (RESS) mode if capable of being driven in RESS mode only. This allows an HEV's pure electric range to be measured. HEVs are also tested in the manufacturer-specified normal operating (combined) mode with testing to commence at 100% state-of-charge. When applicable, both miles-per-gallon of fuel and the miles-per-kilowatt-hour will be captured as well as the HEV's range when operated in pure electric mode.

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Hybrid-electric vehicles (HEVs) HEV

combine the benefits of gasoline engines and electric motors and can be

configured to obtain different objectives, such as improved fuel economy, increased power, or additional auxiliary power for electronic devices and power tools. Some of the advanced technologies typically used by hybrids include



Regenerative Braking. The electric motor applies resistance to the drive train causing the wheels to slow down. In return, the energy from the wheels turns the motor, which functions as a generator, converting energy normally wasted during coasting and braking into electricity, which is stored in a battery until needed by the electric motor.



Electric Motor Drive/Assist. The electric motor provides additional power to assist the engine in accelerating, passing, or hill climbing. This allows a smaller, more efficient engine to be used. In some vehicles, the motor alone provides power for low-speed driving conditions where internal combustion engines are least efficient.



Automatic Start/Shutoff. Automatically shuts off the engine when the vehicle comes to a stop and restarts it when the accelerator is pressed. This prevents wasted energy from idling.

Electric / Hybrid Vehicle Components With the growing requirements to improve fuel economy

and

reduce

emissions,

car

manufacturers are responding by developing more hybrid electric vehicles (HEVs) and fuel cell

hybrid

vehicles

(FCHVs).

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Since the 1990s, DENSO has closely worked with car manufacturers to develop state-of-the-art components for those hybrid vehicles. In 1997, DENSO started supplying components for HEVs, including a battery electronic control unit (ECU) and DC-DC converter. In 2001, DENSO launched the world’s first belt-driven integrated starter generator (ISG) that integrated the starter with the alternator, realizing an idle stop function. In the field of air conditioners for hybrid vehicles, DENSO launched an electric air conditioner for HEVs in 2003. DENSO can supply components to various types of hybrid vehicles and help to create new generation vehicles.

Hybrid Electric Vehicle Configuration

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Battery ECU The battery electronic control unit (ECU) detects voltages and current of the main battery in hybrid electric vehicles (HEV) and calculates the main battery’s state of charge (SOC) to: 

maintain an appropriate SOC



prevent over-charge and over-discharge of the main battery

The battery ECU also detects: 

main battery abnormalities



degree of the main battery deterioration



accidental

electrical

connection

between

the

high-voltage

part

and the body DENSO provides battery ECUs for nickel metal hydride batteries as well as lithium ion batteries.

DC-DC Converter The DC-DC converter converts the main battery’s high voltage (200 to 400 volts) to the auxiliary battery’s lower voltage (12 volts) and charges the auxiliary battery. The DC-DC converter also serves as a power source for 12-volt equipment including headlamps, windshield wipers and horns. In 1997, DENSO started supplying the DC-DC converter for hybrid electric vehicles. DENSO Technology – Leading the World 

In 2000, DENSO launched a compact DC-DC converter that achieved the world’s largest output current – 100 amperes.

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Benefits and Features 

High reliability o



Adopting an isolated converter circuit.

Small size and light weight o

Reducing the size of magnetic parts by increasing the frequency.

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Current and Future Electric Cars Many automakers have plans to produce electric cars--also known as an electric vehicle (EV). Past EVs never gained popularity and had notoriously poor performance, short battery life and long recharge times. But automakers are confident that advances in technology will ensure that the next generation of electric cars will satisfy the needs of today's drivers. Here are a few models scheduled to appear in showrooms soon. Tesla Motors Tesla Motors was founded in 2003 and quickly earned worldwide attention following the unveiling of the Tesla Roadster in 2006. This two-seater sports car accelerates from 0 to 60 mph in 3.9 seconds and has a travel range of more than 200 miles on a fully charged battery. The Roadster's efficiency and performance showcases the company's belief that an electric car can be both environmentally friendly and exciting to drive. The base MSRP is $101,500, which includes a $7,500 federal electric car tax credit. A "Sport" version is also available for an additional $19,500 and includes a sport adjustable suspension, performance tires and a 0-60 time of 3.7 seconds. For those needing more room, Tesla is currently taking reservations for their upcoming Model S; an electric sedan that the company says will accommodate seven passengers. Varying battery and charging options will give the Model S a range of up to 300 miles and a charge time as fast as 45 minutes. Deliveries of the Model S are scheduled for late 2011 and the estimated price is $49,900 (including the tax credit). Chevrolet Volt The Volt is a five-passenger sedan that travels on pure electricity for an estimated 40 miles per battery charge. For longer trips or when charging is not possible, the Volt automatically switches to an onboard range extender, a gasoline-powered generator

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that creates more electricity to power the car. Chevrolet says the range extender will allow the Volt to travel an additional 300 miles per tank. The Volt is in showrooms at around $40,000. Fisker Karma Fisker Automotive is another start-up that the Karma, a four-passenger luxury sedan that uses a system almost identical to the Chevrolet Volt. The Karma has a 50-mile range on pure electricity before switching to a gasoline-powered generator that provides power for 300 miles per tank. The base price is around $87,000 (before tax credits are applied). Smart ForTwo Electric Smart is currently testing and researching an electric version of the For Two, which has an estimated range of 80 miles per charge. We should see the electric smart by 2012. Prices haven't been announced. Nissan Leaf The Leaf, a five-passenger sedan with an estimated 100-mile range per charge, was released in late 2010. The Leaf sells for around $36,000. You can expect this list of electric cars to grow as more customers look for alternatives to gasoline due to fluctuating gas prices and concern for the environment. Is an Electric Car Right for You? There are a couple of things to consider if buying an electric car is the right decision for you. Price One major factor is your price range. Some electric cars can go for over $100,000, so if you want to save money you may want to go with a hybrid instead. Because electricity is cheaper than gas, it is true that you can save money over time by driving an all electric car, but it takes a long time for the price to even out.

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Speed Electric cars are not made to go fast, and the current top speed of most models is less than 60 miles per hour. If you like to drive your car faster than that, an all electric car is probably not the best choice for you. That being said, if you will primarily use the electric car for short in-city commutes, an electric car is an excellent choice. Hybrid-car Performance The key to a hybrid car is that the gasoline engine can be much smaller than the one in a conventional car and therefore more efficient. Most cars require a relatively big engine to produce enough power to accelerate the car quickly. In a small engine, however, the efficiency can be improved by using smaller, lighter parts, by reducing the number of cylinders and by operating the engine closer to its maximum load. There are several reasons why smaller engines are more efficient than bigger ones: 

The big engine is heavier than the small engine, so the car uses extra energy every time it accelerates or drives up a hill.



The pistons and other internal components are heavier, requiring more energy each time they go up and down in the cylinder.



The displacement of the cylinders is larger, so more fuel is required by each cylinder.



Bigger engines usually have more cylinders, and each cylinder uses fuel every time the engine fires, even if the car isn't moving.

This explains why two of the same model cars with different engines can get different mileage. If both cars are driving along the freeway at the same speed, the one with the smaller engine uses less energy. Both engines have to output the same amount of power to drive the car, but the small engine uses less power to drive itself. But how can this smaller engine provide the power your car needs to keep up with the more powerful cars on the road? Let's compare a car like the Chevy Camaro, with its big V-8 engine, to our hybrid car with its small gas engine and electric. The engine in the Camaro has more than enough power to handle any driving situation. The engine in the hybrid car is powerful enough to move the car along on the freeway, but when it needs to get the car moving in a hurry, or go up a steep hill, it needs help. That "help" comes from the

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electric motor and battery -- this system steps in to provide the necessary extra power. The gas engine on a conventional car is sized for the peak power requirement (those few times when you floor the accelerator pedal). In fact, most drivers use the peak power of their engines less than one percent of the time. The hybrid car uses a much smaller engine, one that is sized closer to the average power requirement than to the peak power.

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CHAPTER 8 FUELL CELL POWER VEHICLES INTRODUCTION FCVs are powered by fuel cells, which generate electricity from hydrogen, which is not only environmentally friendly and highly energy-efficient, but can also be produced using a variety of readily available raw materials. Thanks to these characteristics, fuel cell vehicles are ideal for achieving sustainable mobility. Therefore, Toyota is striving to make this vehicle technology widely available as soon as possible. Fuel-cell electric vehicles (FCEVs) are another type of zero-emission vehicle producing no CO2 or other emissions. FCEVs are the obvious next step to complement today's battery electric vehicles as our industry embraces more sustainable transportation. Powered by electricity generated from hydrogen and oxygen, they emit only water during driving. Our FCEVs make use of the lithium-ion batteries and high-power electric systems re fined in our EV development, as well as the control systems from our hybrid vehicles and the high-pressure gas storage technologies from our compressed natural gas vehicles (CNG Vs). In January 2011, Nissan announced efforts with 12 other companies to launch FCEVs and to develop the hydrogen supply infrastructure in Japan. Development is now progressing toward achieving these goals within this decade. In October 2011, we released our Next Generation Fuel Cell Stack for FCEVs. This model features improvements to the membrane electrode assembly making up the fuel cells and to the separator flow channel, giving a power density 2.5 times greater than the 2005 model and, at 2.5 kW per liter. The use of platinum and the variation of parts have both been reduced to a quarter of the levels of the 2005 model, and the siz e has been substantially reduced to less than half that of existing models. With these improvements, we have reduced the cost of the new fuel cell stack to one sixth that of the 2005 model.

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In January 2013, Daimler AG, Ford Motor Company and Nissan Motor Co., Ltd., under the Alliance with Renault, have signed a unique three-way agreement for the joint development of common fuel cell system. The goal of the collaboration is to jointly develop a common FCEV system while reducing investment costs associated with the engineering of the technology, and deriving efficiencies through economies of scale, and will help to launch the world's first affordable, mass-market FCEVs as early as 2017. Types of Fuel Cells The fuel cell will compete with many other energy­ conversion devices, including the gas turbine in your city's power plant, the gasoline engine in your car and the battery in your laptop. Combustion engines like the turbine and the gasoline engine burn fuels and use the pressure created by the expansion of the gases to do mechanical work. Batteries convert chemical energy back into electrical energy when needed. Fuel cells should do both tasks more efficiently. A fuel cell provides a DC (direct current) voltage that can be used to power motors, lights or any number of electrical appliances. There are several different types of fuel cells, each using a different chemistry. Fuel cells are usually classified by their operating temperature and the type of electrolyte they use. Some types of fuel cells work well for use in stationary power generation plants. Others may be useful for small portable applications or for powering cars. The main types of fuel cells include: Polymer exchange membrane fuel cell (PEMFC) The Department of Energy (DOE) is focusing on the PEMFC as the most likely candidate for transportation applications. The PEMFC has a high power density and a relatively low operating temperature (ranging from 60 to 80 degrees Celsius, or 140 to 176 degrees Fahrenheit). The low operating temperature means that it doesn't take very long for the fuel cell to warm up and begin generating electricity. Solid oxide fuel cell (SOFC) These fuel cells are best suited for large-scale stationary power generators that could provide electricity for factories or towns. This type of fuel cell operates at very high temperatures (between 700 and 1,000 degrees Celsius). This high temperature makes reliability a problem, because parts of the fuel cell can break down after

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cycling on and off repeatedly. However, solid oxide fuel cells are very stable when in continuous use. In fact, the SOFC has demonstrated the longest operating life of any fuel cell under certain operating conditions. The high temperature also has an advantage: the steam produced by the fuel cell can be channeled into turbines to generate more electricity. This process is called co-generation of heat and power (CHP) and it improves the overall efficiency of the system. Alkaline fuel cell (AFC) This is one of the oldest designs for fuel cells; the United States space program has used them since the 1960s. The AFC is very susceptible to contamination, so it requires pure hydrogen and oxygen. It is also very expensive, so this type of fuel cell is unlikely to be commercialized. Molten-carbonate fuel cell (MCFC) Like the SOFC, these fuel cells are also best suited for large stationary power generators. They operate at 600 degrees Celsius, so they can generate steam that can be used to generate more power. They have a lower operating temperature than solid oxide fuel cells, which means they don't need such exotic materials. This makes the design a little less expensive. Phosphoric-acid fuel cell (PAFC) The phosphoric-acid fuel cell has potential for use in small stationary powergeneration systems. It operates at a higher temperature than polymer exchange membrane fuel cells, so it has a longer warm-up time. This makes it unsuitable for use in cars. Direct-methanol fuel cell (DMFC) Methanol fuel cells are comparable to a PEMFC in regards to operating temperature, but are not as efficient. Also, the DMFC requires a relatively large amount of platinum to act as a catalyst, which makes these fuel cells expensive. In the following section, we will take a closer look at the kind of fuel cell the DOE plans to use to power future vehicles -- the PEMFC. Polymer Exchange Membrane Fuel Cells The polymer exchange membrane fuel cell (PEMFC) is one of the most promising fuel cell technologies. This type of fuel cell will probably end up powering cars, buses

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and maybe even your house. The PEMFC uses one of the simplest reactions of any fuel cell. First, let's take a look at what's in a PEM fuel cell: In Figure 1 you can see there are four basic elements of a PEMFC: 

The anode, the negative post of the fuel cell, has several jobs. It conducts the electrons that are freed from the hydrogen molecules so that they can be used in an external circuit. It has channels etched into it that disperse the hydrogen gas equally over the surface of the catalyst.



The cathode, the positive post of the fuel cell, has channels etched into it that distribute the oxygen to the surface of the catalyst. It also conducts the electrons back from the external circuit to the catalyst, where they can recombine with the hydrogen ions and oxygen to form water.



The electrolyte is the proton exchange membrane. This specially treated material, which looks something like ordinary kitchen plastic wrap, only conducts positively charged ions. The membrane blocks electrons. For a PEMFC, the membrane must be hydrated in order to function and remain stable.



The catalyst is a special material that facilitates the reaction of oxygen and hydrogen. It is usually made of platinum nanoparticles very thinly coated onto carbon paper or cloth. The catalyst is rough and porous so that the maximum surface area of the platinum can be exposed to the hydrogen or oxygen. The platinum-coated side of the catalyst faces the PEM. When an H2 molecule comes in contact with the platinum on the catalyst, it splits into two H+ ions and two electrons (e-). The electrons are conducted through the anode, where they make their way through the external circuit (doing useful work such as turning a motor) and return to the cathode side of the fuel cell. Meanwhile, on the cathode side of the fuel cell, oxygen gas (O 2) is being forced through the catalyst, where it forms two oxygen atoms. Each of these atoms has a strong negative charge. This negative charge attracts the two H+ ions through the membrane, where they combine with an oxygen atom and two of the electrons from the external circuit to form a water molecule (H2O).

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This reaction in a single fuel cell produces only about 0.7 volts. To get this voltage up to a reasonable level, many separate fuel cells must be combined to form a fuel-cell stack. Bipolar plates are used to connect one fuel cell to another and are subjected to both oxidizing and reducing conditions and potentials. A big issue with bipolar plates is stability. Metallic bipolar plates can corrode, and the byproducts of corrosion (iron and chromium ions) can decrease the effectiveness of fuel cell membranes and electrodes.Low-temperature

fuel

cells

use lightweight

metals, graphite and carbon/thermoset composites (thermoset is a kind of plastic that remains rigid even when subjected to high temperatures) as bipolar plate material.

Honda's FCX Concept Vehicle Fuel Cell Efficiency Pollution reduction is one of the primary goals of the fuel cell. By comparing a fuelcell-powered car to a gasoline-engine-powered car and a battery-powered car, you can see how fuel cells might improve the efficiency of cars today. Since

all

three

types

of

cars

have

many

of

the

same

components

(tires, transmissions, et cetera), we'll ignore that part of the car and compare efficiencies up to the point where mechanical power is generated. Let's start with the fuel-cell car. (All of these efficiencies are approximations, but they should be close enough to make a rough comparison.)

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If the fuel cell is powered with pure hydrogen, it has the potential to be up to 80percent efficient. That is, it converts 80 percent of the energy content of the hydrogen into electrical energy. However, we still need to convert the electrical energy into mechanical work. This is accomplished by the electric motor and inverter. A reasonable number for the efficiency of the motor/inverter is about 80 percent. So we have 80-percent efficiency in generating electricity, and 80-percent efficiency converting it to mechanical power. That gives an overall efficiency of about 64 percent. Honda's FCX concept vehicle reportedly has 60-percent energy efficiency. If the fuel source isn't pure hydrogen, then the vehicle will also need a reformer. A reformer turns hydrocarbon or alcohol fuels into hydrogen. They generate heat and produce other gases besides hydrogen. They use various devices to try to clean up the hydrogen, but even so, the hydrogen that comes out of them is not pure, and this lowers the efficiency of the fuel cell. Because reformers impact fuel cell efficiency, DOE researches have decided to concentrate on pure hydrogen fuel-cell vehicles, despite challenges associated with hydrogen production and storage. Gasoline and Battery Power Efficiency T­he efficiency of a gasoline-powered car is surprisingly low. All of the heat that comes out as exhaust or goes into the radiator is wasted energy. The engine also uses a lot of energy turning the various pumps, fans and generators that keep it going. So the overall efficiency of an automotive gas engine is about 20 percent. That is, only about 20 percent of the thermal-energy content of the gasoline is converted into mechanical work. A battery-powered electric car has a fairly high efficiency. The battery is about 90percent efficient (most batteries generate some heat, or require heating), and the electric motor/inverter is about 80-percent efficient. This gives an overall efficiency of about 72 percent. But that is not the whole story. The electricity used to power the car had to be generated somewhere. If it was generated at a power plant that used a combustion process (rather than nuclear, hydroelectric, solar or wind), then only about 40

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percent of the fuel required by the power plant was converted into electricity. The process of charging the car requires the conversion of alternating current (AC) power to direct current (DC) power. This process has an efficiency of about 90 percent. So, if we look at the whole cycle, the efficiency of an electric car is 72 percent for the car, 40 percent for the power plant and 90 percent for charging the car. That gives an overall efficiency of 26 percent. The overall efficiency varies considerably depending on what sort of power plant is used. If the electricity for the car is generated by a hydroelectric plant for instance, then it is basically free (we didn't burn any fuel to generate it), and the efficiency of the electric car is about 65 percent. Scientists are researching and refining designs to continue to boost fuel cell efficiency. One approach is to combine fuel cell and battery-powered vehicles. Ford Motors and Airstream are developing a concept vehicle powered by a hybrid fuel cell drivetrain named the HySeries Drive. Ford claims the vehicle has a fuel economy comparable to 41 miles per gallon. The vehicle uses a lithium battery to power the car, while the fuel cell recharges the battery. Fuel-cell vehicles are potentially as efficient as a battery-powered car that relies on a non-fuel-burning power plant. But reaching that potential in a practical and affordable way might be difficult. In the next section, we will examine some of the challenges of making a fuel-cell energy system a reality. Fuel Cell Problems Fuel cells might be the answer to our power problems, but first scientists will have to sort out a few major issues: Cost Chief among the problems associated with fuel cells is how expensive they are. Many of the component pieces of a fuel cell are costly. For PEMFC systems, proton exchange membranes, precious metal catalysts (usually platinum), gas diffusion layers, and bipolar plates make up 70 percent of a system's cost [Source: Basic Research Needs for a Hydrogen Economy]. In order to be competitively priced (compared to gasoline-powered vehicles), fuel cell systems must cost $35 per

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kilowatt. Currently, the projected high-volume production price is $73 per kilowatt .In particular, researchers must either decrease the amount of platinum needed to act as a catalyst or find an alternative. Durability Researchers must develop PEMFC membranes that are durable and can operate at temperatures greater than 100 degrees Celsius and still function at sub-zero ambient temperatures. A 100 degrees Celsius temperature target is required in order for a fuel cell to have a higher tolerance to impurities in fuel. Because you start and stop a car relatively frequently, it is important for the membrane to remain stable under cycling conditions. Currently membranes tend to degrade while fuel cells cycle on and off, particularly as operating temperatures rise. Hydration Because PEMFC membranes must by hydrated in order to transfer hydrogen protons, researches must find a way to develop fuel cell systems that can continue to operate in sub-zero temperatures, low humidity environments and high operating temperatures. At around 80 degrees Celsius, hydration is lost without a highpressure hydration system. The SOFC has a related problem with durability. Solid oxide systems have issues with material corrosion. Seal integrity is also a major concern. The cost goal for SOFC’s is less restrictive than for PEMFC systems at $400 per kilowatt, but there are no obvious means of achieving that goal due to high material costs. SOFC durability suffers after the cell repeatedly heats up to operating temperature and then cools down to room temperature. Delivery The Department of Energy’s Technical Plan for Fuel Cells states that the air compressor technologies currently available are not suitable for vehicle use, which makes designing a hydrogen fuel delivery system problematic. Infrastructure In order for PEMFC vehicles to become a viable alternative for consumers, there must be a hydrogen generation and delivery infrastructure. This infrastructure might

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include pipelines, truck transport, fueling stations and hydrogen generation plants. The DOE hopes that development of a marketable vehicle model will drive the development of an infrastructure to support it. Storage and Other Considerations Three hundred miles is a conventional driving range (the distance you can drive in a car with a full tank of gas). In order to create a comparable result with a fuel cell vehicle, researchers must overcome hydrogen storage considerations, vehicle weight and volume, cost, and safety. While PEMFC systems have become lighter and smaller as improvements are made, they still are too large and heavy for use in standard vehicles. Why Use Fuel Cells? Why is the U.S. government working with universities, public organizations and private companies to overcome all the challenges of making fuel cells a practical source for energy? More than a billion dollars has been spent on research and development on fuel cells. A hydrogen infrastructure will cost considerably more to construct and maintain (some estimates top 500 billion dollars). Why does the president think fuel cells are worth the investment? The main reasons have everything to do with oil. America must import 55 percent of its oil. By 2025 this is expected to grow to 68 percent. Two thirds of the oil Americans use every day is for transportation. Even if every vehicle on the street were a hybrid car, by 2025 we would still need to use the same amount of oil then as we do right now. In fact, America consumes one quarter of all the oil produced in the world, though only 4.6 percent of the world population lives here Experts expect oil prices to continue to rise over the next few decades as more lowcost sources are depleted. Oil companies will have to look in increasingly challenging environments for oil deposits, which will drive oil prices higher. Concerns extend far beyond economic security. The Council on Foreign Relations released a report in 2006 titled "National Security Consequences of U.S. Oil Dependency." A task force detailed numerous concerns about how America's

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growing reliance on oil compromises the safety of the nation. Much of the report focused on the political relationships between nations that demand oil and the nations that supply it. Many of these oil rich nations are in areas filled with political instability or hostility. Other nations violate human rights or even support policies like genocide. It is in the best interests of the United States and the world to look into alternatives to oil in order to avoid funding such policies. Using oil and other fossil fuels for energy produces pollution. Pollution issues have been in the news a lot recently -- from the film "An Inconvenient Truth" to the announcement that climate change and global warming would factor into future adjustments of the Doomsday Clock. It is in the best interest for everyone fined an alternative to burning fossil fuels for energy. Fuel cell technologies are an attractive alternative to oil dependency. Fuel cells give off no pollution, and in fact produce pure water as a byproduct. Though engineers are concentrating on producing hydrogen from sources such as natural gas for the short-term, the Hydrogen Initiative has plans to look into renewable, environmentallyfriendly ways of producing hydrogen in the future. Because you can produce hydrogen from water, the United States could increasingly rely on domestic sources for energy production. Other countries are also exploring fuel-cell applications. Oil dependency and global warming are international problems. Several countries are partnering to advance research and development efforts in fuel cell technologies. One partnership is The International Partnership for the Hydrogen Economy. SOLAR CARS Solar cars have been developed in the last twenty years and are powered by energy from the sun. Although they are not a practical or economic form of transportation at present, in the future they may play a part in reducing our reliance on burning fossil fuels such as petrol and diesel.

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A solar powered racing car is shown above. These are expensive to produce and usually seat only one or two people. The main cost is due to the large number of expensive and delicate photovoltaic solar panels that are needed to power the vehicle. Also, many of the solar powered cars used in races today are composed of expensive, lightweight materials such as titanium composites. These materials are normally used to manufacture fighter jets. Carbon fiber and fiber glass are also used for much of the bodywork. Most of the cars used in races are hand made by specialist teams and this adds to the expense. A solar powered vehicle can only run efficiently when the sun shines, although most vehicles of this type have a battery backup. Electricity is stored in the batteries when the sun is shining and this power can be used when sun light is restricted (cloudy). The batteries are normally nickel-metal hydride batteries (NiMH), Nickel-Cadmium batteries (NiCd), Lithium ion batteries or Lithium polymer batteries. Common lead acid batteries of the type used in the average family car are too heavy. Solar powered cars normally operate in a range of 80 to 170 volts. To reduce friction with the ground the wheels are extremely narrow and there are usually only three.

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Some solar powered cars are practical and one is shown below. This is a solar powered golf cart and it can be used in sunny climates to carry golfers from one hole to the next. When it is standing still the solar panels charge up the batteries and it is the batteries that power the electric motors, directly. As the vehicle is not in continuous use the batteries have time to charge up before they are needed.

One of the more realistic ways in which that solar powered car could become practical is to charge up their batteries when they are parked, during the day. Imagine driving the short distance to work and plugging the car into a set of photovoltaic solar panels. Whilst you are working the batteries charge up ready for use for the journey home. The same procedure could be carried out when the car is parked at home. A combination of solar power and wind power may prove to be a method of charging the batteries of ‘electric cars’.

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PHOTOVOLTAIC CELL Photovoltaics is the direct conversion of light into electricity at the atomic level. Some materials exhibit a property known as the photoelectric effect that causes them to absorb photons of light and release electrons. When these free electrons are captured, an electric current results that can be used as electricity. The photoelectric effect was first noted by a French physicist, Edmund Bequerel, in 1839, who found that certain materials would produce small amounts of electric current when exposed to light. In 1905, Albert Einstein described the nature of light and the photoelectric effect on which photovoltaic technology is based, for which he later won a Nobel prize in physics. The first photovoltaic module was built by Bell Laboratories in 1954. It was billed as a solar battery and was mostly just a curiosity as it was too expensive to gain widespread use. In the 1960s, the space industry began to make the first serious use of the technology to provide power aboard spacecraft. Through the space programs, the technology advanced, its reliability was established, and the cost began to decline. During the energy crisis in the 1970s, photovoltaic technology gained recognition as a source of power for non-space applications.

The diagram above illustrates the operation of a basic photovoltaic cell, also called a solar cell. Solar cells are made of the same kinds of semiconductor materials, such as silicon, used in the microelectronics industry. For solar cells, a thin semiconductor wafer is specially treated to form an electric field, positive on one side and negative on the other. When light energy strikes the solar cell, electrons are knocked loose from the atoms in the semiconductor material. If electrical conductors are attached to the positive and negative sides, forming an electrical circuit, the electrons can be

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captured in the form of an electric current -- that is, electricity. This electricity can then be used to power a load, such as a light or a tool. A number of solar cells electrically connected to each other and mounted in a support structure or frame is called a photovoltaic module. Modules are designed to supply electricity at a certain voltage, such as a common 12 volts system. The current produced is directly dependent on how much light strikes the module.

Multiple modules can be wired together to form an array. In general, the larger the area of a module or array, the more electricity that will be produced. Photovoltaic modules and arrays produce direct-current (dc) electricity. They can be connected in both series and parallel electrical arrangements to produce any required voltage and current combination. Today's most common PV devices use a single junction, or interface, to create an electric field within a semiconductor such as a PV cell. In a single-junction PV cell, only photons whose energy is equal to or greater than the band gap of the cell material can free an electron for an electric circuit. In other words, the photovoltaic response of single-junction cells is limited to the portion of the sun's spectrum whose

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energy is above the band gap of the absorbing material, and lower-energy photons are not used. One way to get around this limitation is to use two (or more) different cells, with more than one band gap and more than one junction, to generate a voltage. These are referred to as "multijunction" cells (also called "cascade" or "tandem" cells). Multijunction devices can achieve a higher totalconversion efficiency because they can convert more of the energy spectrum of light to electricity. As shown below, a multijunction device is a stack of individual single-junction cells in descending order of band gap (Eg). The top cell captures the high-energy photons and passes the rest of the photons on to be absorbed by lower-band-gap cells.

HYBRID GAS TURBINE ELECTRIC CAR The C-X75 is a plug-in hybrid with four in-wheel electric motors. Make that four, 195 hp, motors that combine to vault the C-X75 to 60 mph in just three seconds. Once the battery is charged, the car can theoretically travel—it's a concept and not a prototype—roughly 70 miles. To extend the range without having to stop and wait for the batteries to charge, a pair of small gas turbine engines can supply 180 horsepower. While the car's battery-depleted performance won't be nearly as strong, at least it can travel an additional 500 miles or so before a fill-up. The intrigue here is the sewer-piped sized turbine motors that are mounted behind the two front seats. They're roughly two-feet long with a coffee can diameter. These "micro" turbines as they are called are made by a company called Bladon Jets in England

and

they're

custom

made

for

backup

power

generator.

Auto makers are investigating several alternatives to piston-powered backup generators to alleviate the range anxiety associated with EVs. Current piston, gasfired engines are relatively efficient on a thermodynamic scale, but wildly inefficient on a weight per power basis. "Each micro turbine on the C-X75," says Dr Anthony Harper, Jaguar's head of Research and Advanced Engineering, "weighs just 80

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pounds, including the generator. A piston engine that produces similar power would weigh five times as much." Harper conceded that the turbine engine is "about 20 percent" efficient with its fuel as compared to the low 30s for a piston gas engine. But in the case of a plug-in hybrid, less weight takes precedence because the lighter the car, the longer it can travel on just the batteries. The engine is only meant for occasional use, so the benefits of fewer pounds are more often realized. To increase the efficiency, the turbine engines are presently tuned to run at a constant 80,000 rpm. And Harper noted that the turbines can burn a variety of fuels,—kerosene, diesel, ethanol— without major changes. Presently, the micro-turbine powertrain is still very much in the testing phase. Harper explained that the engines create a lot of noise and heat that must be managed. But he thinks there's promise in the design and barring a major setback, we could see a micro-turbine powered plug-in hybrid sometime in the next five years. changes.

JAGUAR CX75

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FUEL CELL POWERED CAR There are some great benefits to a nuclear-powered car. It would rarely need to be refueled -- perhaps every three to five years. Highly enriched uranium is so potent that just one pound can power a submarine or aircraft carrier. Even smaller amounts could conceivably power a car. Assuming the car is adequately shielded (a subject we'll discuss later), the car would put out almost no emissions. And forget turning the ignition: Your nuclear-powered car would be always on -- although that means it would likely need batteries to store the energy constantly being produced by the miniplant. Perhaps the main thing standing in the way of creating a nuclear-powered car is this: The power source is radioactive, so this vehicle would require lots of shielding. Without proper shielding, the radioactivity of the power source could kill people in and near the car, putting a damper on any commute. Nuclear power plants and nuclear-powered aircraft carriers and subs all employ heavy shielding. Nuclear power plants generally have three layers of shielding in addition to the containment structure, which is made of concrete several feet thick and houses the reactor. U.S. law requires most reactors to have these layers of shielding and containment. Government-operated reactors are an exception, though the exact amount of shielding used on aircraft carriers and submarines remains classified. With all of this shielding needed to protect against radioactivity, expect your nuclearpowered car to be extremely heavy. Reproducing the shielding of a nuclear reactor on an appropriate scale may make the car practically immobile. The shielding must also be resistant to earthquakes and other trauma and must be airtight so that air laden with radioactive molecules can't escape. When someone mentions a nuclear-powered car, the danger of radioactivity likely comes to mind. Having radioactive material readily available is a security and public health concern. While not all fuel used in nuclear reactors can be immediately used in a nuclear bomb, even uranium that's not highly enriched could be used in a dirty bomb or other harmful radiological device. Our nuclear-powered car would have to

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be immune from such tampering. Then there's also the question of what happens in a car accident. Would the shielding stay intact, even in a catastrophic collision? Finally, energy companies, car manufacturers and the government would need to collaborate to establish the infrastructure and a standardized process to dispose of spent fuel, which would be highly radioactive for hundreds of years. Other problems associated with nuclear power include the startup costs and time (up to 10 years) for new plants. Then there is the fear of accidents and the need to safely dismantle old plants and dispose of spent fuel and waste. The rekindled interest in nuclear energy has also driven up the price of uranium. The logistics and costs of such an endeavor may prove prohibitive.

Cadillac nuclear fuel concept

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