e8-159
e8/PPA Grid Connected Solar PV Workshop
November 2010
Programme
1
e8/PPA Grid Connected Solar PV Workshop Program DAY COUNT
Day
Time
Program
08:00
Course Opening Ceremony
08:15
What is e8?
09:00
Overview of Grid Connected Solar Applications
09:30
Interaction with the grid. Stability, penetration, islanding, net-metering
Resposibility PPA / KANSAI e8ＧＳ
Day 1
(Mon)
10:00
Morning tea
10:15
Site surveys
10:30
Solar panels, specifications, rating and general characteristics
12:00
Lunch Time
13:00
Practical works with solar panels
15:00
Afternoon tea
15:30
General Inverter characteristics - types, history and general concepts
16:00～16:30 Quiz 08:00
Review of Previous Day
08:30
Matching string characteristics to the Inverter
Dr. Wade
ALL ALL
Day 2
(Wed)
10:00
Morning Tea
10:15
BOS components and their characteristics
10:45
Utility Responsibilities - standards and inspections
11:15
Steps for installing a typical residential grid-connected PV system
12:00
Lunch Time
13:00
Larger installations. Paralleling Strings for increased power output
13:30
Data acquisition, collection and analysis
14:00
Economics of Grid Connected Solar
14:30
Practical works - system design (afternoon tea as desired)
16:00～16:30 Quiz 08:00
Review of Previous Day
08:30
SHS, mini grid (PV mini grid)
09:30
Mini grid (PV hybrid systems within minig-grid)
10:00
Morning tea
10:15
Normal Grid(Examples of grid connected system)
11:00
Technical requirements for grid interconncetion
12:00
Lunch Time
13:00
Technical requirements for grid interconncetion (continuation)
Dr. Wade
ALL ALL
Day3
(Wed)
15:00
Afternoon tea
15:15
Exercise - technical requirements for grid interconnection
16:00～16:30 Quiz 08:00
Review of Previous Day
08:30
Technical requirements for grid interconncetion (continuation)
10:00
Morning tea
10:15
Guidline of Construction & maintenance
12:00
Lunch Time
KANSAI
ALL ALL
Day4
(Thu)
13:00
PV Hybrid system (Various type of power source)
14:00
Quiz
14:30
Site visit
08:00
Review of Previous Day
KANSAI
ALL
Day 5
(Fri)
09:00
Course review and evaluation
10:00
Morning tea
10:30
Closing Ceremony & Provision of Certification
11:30
Farewell Lunch
ALL
CV's
1
- Photo -
Luis Calzado Project Advisor Delegate from: e8 General Secretariat 505 de Maisonneuve Blvd. Lobby Montreal H3A 3C2 Canada
Tel.: +1 (514) 392-8908 Fax: +1 (514) 392-8900 e-mail:
[email protected]
PROFESSIONAL BACKGROUND Since 2005
e8 General Secretariat - Project Committee Member - Policy Committee Member - Project Advisor, e8 Tuvalu solar power project - Project Advisor, e8 Nicaragua Hydro CDM Project - Project Advisor, e8 Maghreb Water and Electricity - Project Advisor, e8 Education for Sustainable Energy Development project - Project Advisor, e8 Rural Electrification Project Sub-Saharan Africa - Project Advisor, e8 Rural Electrification Project Western Africa - Project Advisor, e8 Photovoltaic System Workshop, Pacific Islands - Project Advisor, e8 Demand Side Management Workshop, Pacific Islands - e8 member ESED Committee Member
1993-1995
Abotel and Hostotel . - Information Technology consultant - Database creation and administration
EDUCATION 2007- 2009
McGill University (Montreal, Canada) Post -Graduate Degree International Business
2001-2005
Queen's University (Kingston, Canada) Bachelor of Electrical Engineering
1999-2001
Alliance Française (Paris, France) Diplôme de Langue Française
LANGUAGES English Spanish French Italian
Fluent Fluent Fluent Conversational
ASSOCIATIONS Institute of Electrical and Electronic Engineers (IEEE) Ordre des Ingenieurs du Quebec (OIQ)
Takaya FUYUKI
Delegate from: The Kansai Electric Power Co., Inc 3-6-16 Nakanoshima Kita-Ku Osaka 530-8270 Japan
Tel.: +81-(6)-6441-8821 Fax: +81-(6)-6441-4277 e-mail:
[email protected]
PROFESSIONAL BACKGROUND Aug. 2008
-Oct. 2010 Apr. 2004
-Aug. 2008
The Kansai Electric Power Co., Inc (KANSAI) KANSAI) - Head Office System Planning Group power system planner
The Kansai Electric Power Co., Inc (KANSAI) KANSAI) - Kyoto Branch Office
substation maintenance engineer, substation designer, power system
planner
EDUCATION 2002-2004
Graduate school of OSAKA University
1998-2002
OSAKA University (Japan)
Department of Engineering Science, Electrical Engineering Department of Engineering Science, Electrical Engineering
LANGUAGES Japanese
Mother tongue
English
Very good (speaking, reading, writing)
Taiichi Kaizuka Project Manager Delegate from: The Kansai Electric Power Co., Inc 3-6-16 Nakanoshima Kita-Ku Osaka 530-8270 Japan
Tel.: +81-(6)-6441-8821 Fax: +81-(6)-6441-4277 e-mail:
[email protected]
PROFESSIONAL BACKGROUND Since 2010 KANSAI Manager, International cooperation group Work for e8 and international relationship
2008-2010
KANSAI Manager, Network Wheeling Center Power Wheeling for Power Produce and Supplier
2005-2008
The Federation of Electric Power Companies of Japan Deputy general Manager, Power System Planning and Operation Engaged in deregulation of Japanese Power Utilities
2001-2005
KANSAI Manager, Power system planning Planning of 500kV power system, Forecast of system peak demand
1999-2001
KANSAI Manager, Electric Power Engineering Electric power engineering of Power Quality
1997-1999
KANSAI Assistant manager, Office of operation and maintenance office Operation and maintenance of substation
1996-1997
Japan Electric Power Information Center Researcher, planning section Research Energy situation of foreign countries
1990-1996
KANSAI Electrical Engineer Planning of power system, Design of 77kV substations
EDUCATION
1984-1988
Osaka University (Osaka, Japan) Bachelor of Electronic Engineering
1988-1990
Osaka University (Osaka, Japan) Master of Electronic Engineering
ASSOCIATIONS
The institute of Electrical Engineers of Japan (IEEJ)
LANGUAGES Japanese
Mother tongue
English
Very Good (speaking, reading, writing)
Tomohiro KANNO Project Leader Delegate from: The Kansai Electric Power Co., Inc 3-6-16 Nakanoshima Kita-Ku Osaka 530-8270 Japan
Tel.: +81-(6)-6441-8821 Fax: +81-(6)-6441-4277 e-mail:
[email protected]
PROFESSIONAL BACKGROUND Since Jun.2009
The Kansai Electric Power Co., Inc (KANSAI) KANSAI) - Project leader of e8/PPA DSM workshop
- Project leader of e8/PPA Grid-Connected PV system workshop
- Assistant of e8 ESED project
- Accounting Management of Paris Office
Apr.2007
The Kansai Electric Power Co., Inc (KANSAI) KANSAI)
- Kyoto Branch Office business strategic planner
EDUCATION 2003-2007
WASWDA University (Tokyo, Japan)
Department of Politics and Economics
LANGUAGES Japanese
Mother tongue
English
Very Good (speaking, reading, writing)
Chinese
Good (speaking, reading, writing)
-
Herbert WADE
-
Delegate from: 90/40 Bangkapi Condo ‘S’ Soi 121 Lad Phrao Bangkok 10240 THAILAND
Tel.: +662-733-7061 Fax: +662-733-7061 e-mail:
[email protected]
PROFESSIONAL BACKGROUND 1993-Present
5ndependent Consultant - Renewable energy, rural electrification, development policy
1989-1993
South Pacific Institute for Renewable Energy (Tahiti) - International Programme Manager
1984-1993
UN Pacific Energy Development Programme (Fiji) - Senior Energy Planner/Deputy Project Manager
1982-1984
Fiji Department of Energy - Director
EDUCATION 1961
United States Naval Academy, (Annapolis, Maryland, USA) BSc (Engineering)
1967
University of Rhode Island (Kingston, R.I., USA) MBA (Management)
PUBLICATIONS 2002
Herb Wade, Solar Project Development, NESCO, Paris
2003
Herb Wade, Solar Photovoltaic Technical Training Manual, UNESCO, Paris
1994
Liebenthal, Mathur, Wade, World Bank Technical Paper 244, “Solar Energy: esons from the Pacific Experience”
1985
Gowan, Wade, “A Manual for Rnewable Energy Assessment, An Energy Planner’s Guide”, East West Center, Hawaii, USA
1983
Herb Wade, “Building Underground”, Rodale Press, Emmaus, PA, USA
LANGUAGES English
Native
Thai
Limited Conversational
French
Limited Conversational/Technical reading
Russian
Limited reading
ASSOCIATIONS International Solar Energy Society American Solar Energy Association International Association for Solar Energy Education Arizona Solar Energy Association Midwest Solar Energy Association
Day 1
1
The e8: Implementing Sustainable Energy Development Worldwide
Implementing Sustainable Energy Development Worldwide
1
e8 Member Companies
The e8: Implementing Sustainable Energy Development Worldwide
• • • •
10 major electricity companies from the global electricity sector At the recent Tokyo Summit, the e8 opened its membership to the major companies of the emerging countries New member (2010): Eletrobras (Brazil) New partner (2010): Comisión Federal de Electricidad (Mexico) as partner
HQ AEP
Duke Energy
EDF
RWE ENEL
RusHydro TEPCO KANSAI
Eletrobras
2
1
The e8: Implementing Sustainable Energy Development Worldwide
e8 Strategic Objectives
• Develop joint policy frameworks and implement related initiatives; • Take joint positions on global electricity-related issues; • Provide human capacity building assistance on the efficient generation and use of electricity; • Demonstrate replicable small-scale renewable energy projects.
3
The e8: Implementing Sustainable Energy Development Worldwide
The e8 Fields of Expertise
Power Plant Efficiency
Clean Coal Technology
Demand Side Management
Project Management Strengthening
e8 Activities
Institutional Strengthening
Environmental Impact Assessment Rural Electrification
Renewable Energy
4
2
The e8: Implementing Sustainable Energy Development Worldwide
e8 Projects and Activities Worldwide Tajikistan Georgia Bulgaria
Syria Tunisia Maghreb Lebanon Egypt Jordan
Mexico
Mongolia China Laos Philippines
Nicaragua Burkina Faso, Benin, Niger
Ecuador Bolivia
Cameroon
Paraguay
Zimbabwe
Chile
South Africa
Projects
India Kenya
Malaysia
E7-81 •E7-107 E7-82 Bhutan
Thailand Indonesia Bangladesh
Tuvalu
Madagascar
Capacity Building Completed
5
The e8: Implementing Sustainable Energy Development Worldwide
e8 Capital Projects •
Jordan: AIJ project on thermal power plant efficiency improvements
•
Indonesia: AIJ project on renewable energy supply systems in Indonesia (solar, wind, hybrid, micro-hydro) [Completed, 2000] Benin, Burkina Faso, Niger (W Park): Solar power systems for rural electrification and water supply. [Completed, 2003] Bhutan: CDM-registered project supplying hydro-electricity to a remote village in Bhutan. [Completed, 2005] Ecuador (Galapagos): Re-powering using renewable energy systems such as wind. [Completed, October 2007] Tuvalu (Pacific Islands): Grid-connected solar power installations in Tuvalu. [Completed, February 2008] Ifugao (Philippines): mini hydro project (200 kW) for the preservation of Ifugao's ancient rice terraces [Completed , December 2009] Maghreb: Wind for desalination project. [On-going]
[Completed, 2000]
• • • • • •
6
3
The e8: Implementing Sustainable Energy Development Worldwide
e8 CDM Projects The Bhutan Mini Hydro Power Project (70 kW) was the first e8 project to be officially registered as a Clean Development Mechanism (CDM) project under the terms of the Kyoto Protocol. It was also the first project to be registered in the Himalayan Kingdom of Bhutan. The San Cristobal, Galapagos, Wind Project (2.4 MW): The project was registered as a CDM project with UNFCCC in May 2008.
7
The e8: Implementing Sustainable Energy Development Worldwide
e8 Human Capacity Building Activities •
Seminar on Electricity Interconnection (Ethiopia) [Completed, 2009]
•
Solar PV, Design, O&M (Pacific Islands) [Completed, 2008-2009]
•
Monitoring Hybrid System & Sustainability (Indonesia) [In implementation]
•
Financing Sustainable Electrification Dialogues Workshops 2009-2013 [2 workshops Completed 2009-2010; 6 workshops over the next 3 years]
•
DSM workshop (Pacific Islands)
•
Grid Connected Solar PV, Design, O&M (Pacific Islands)
[Completed, 2009-2010]
[In development 2010]
•
Industrial Energy Efficiency for emerging economies [In development 2010-2011]
8
4
The e8: Implementing Sustainable Energy Development Worldwide
Education for Sustainable Energy Development - ESED • The ESED was created to support outstanding students in pursuing advanced studies in sustainable energy development and to encourage meaningful contributions to the collective body of knowledge about the subject. • The Programme targets students from developing countries and economies in transition who plan to undertake post graduate studies in areas directly related to sustainable energy development. • 9 Post-doctoral scholarships and 55 Masters scholarships awarded since 2001. 9
Galapagos Wind Project
The e8: Implementing Sustainable Energy Development Worldwide
(Completed 2007)
10
5
The e8: Implementing Sustainable Energy Development Worldwide
The e8: Implementing Sustainable Energy Development Worldwide
Tuvalu Solar Power Project (Completed 2008)
11
Ifugao-Ambangal Mini-Hydro Power Project (Completed 2009)
12
6
The e8: Implementing Sustainable Energy Development Worldwide
www.e8.org
13
7
Overview of Grid-Connected Solar PV Dr. Herbert A. Wade
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Grid Connected Solar PV Workshop Republic of Palau November 1-5,2010
What is GridGrid-Connected Solar • Solar panels convert sunlight to DC electricity • An electronic inverter, converts the DC from the solar panels to AC and synchronizes with the grid • Very simple physically with only two major components – Solar panels – Inverter
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Misconception about Grid Connected PV • Grid connected solar does NOT feed its power to the building first then the surplus goes to the grid. All the solar power goes into the grid and all the building power comes from the grid. – The electricity the building uses from the grid is offset by a credit for the energy fed into the grid from the solar This typically is through the use of two meters, one for the energy coming into the building from the grid and one metering the energy going into the grid from the solar
Overall System for GridGrid-Connected PV
Graphic copyright by Global Sustainable Energy Solutions, Ltd. (GSES)
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Concept of Net Metering • Net metering is intended to allow solar PV to send energy into the grid at one time and for the user to take out the equivalent energy at another time – Important for residences since daytime use when the sun is brightest is lowest. Most residential usage is in the evening – Not so important for buildings with high A/C loads since then the maximum load occurs when the solar is strongest
Net Metering Concept in the Pacific • Usually net metering relies on two meters but one meter can be used if it can run backward when power is going into the grid. – Also special electronic meters that read energy flows both ways can be obtained • Net metering needs to be arranged to send forward credit for surplus energy delivered to the grid with an annual accounting. – Solar tends to be seasonal so some months there may be a surplus sent into the grid from solar and some months there will be more used from the grid than sent by the solar
• At some time once a year the total energy delivered to the grid from the solar is subtracted from the total energy delivered to the building from the grid. If there is a surplus of energy sent to the grid by the solar over the year, a payment may be made
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Net Metering – Payment for Surplus
Payment for Surplus Energy from PV – May be legally required or may be up to the utility May range from zero up to more than the per kWh retail charge. If zero encourages users to keep the scale of PV small enough so there is never an annual surplus If greater than retail power rates, encourages large installations to make money Real cost saving to the utility is in fuel as adjusted for the cost of maintaining spinning reserves and for grid maintenance » Major cost savings for PIC utilities since the great majority of per kWh cost is fuel
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Effect on Utility Rates • If many residential customers were to add solar to their buildings, as much as 20% of the load could be lost. This can affect the cost of electricity delivery since investment and maintenance is not reduced though fuel requirements are lower – PIC per kWh energy delivery costs are a combination of fuel cost and the cost of operations and maintenance – Typically 60%-80% of per kWh costs are fuel for PIC utilities – Fuel cost would be reduced while the cost of operations would stay the same but spread over 20% fewer kWh sold – Cost per kWh delivered could rise around 5%-10% according to what percentage of kWh cost is fuel
Components – Solar Panels • Solar Panels (modules) – Crystalline (single crystal and polycrystal cells) Smallest physical size per Wp of capacity Proven useful life of 20+ years in the Pacific
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
– Thin film Cheapest type of panel (currently ~US$2/Wp When new, may be a better performer than crystalline panels in the tropics for grid connected systems Not proven for long life in the tropics
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Panel Connections for Grid-Connected Solar • Panel interconnections – Panels connected in series “strings” to provide proper voltage for inverter input – Connections may be through the use of “quick connect” push-in connectors or screw-type junction boxes Due to prior bad experiences there are concerns about the long term quality of quickconnect (MC-4) cable connections in the highly corrosive and high temperature island environment
Connector Pair (- & +)
Individual connectors
Melting of connector in service in Fiji caused by resistance heating due to salt corrosion
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Panel connections using standard junction box
Panel Mounting • Roof mount – – – – – –
Lowest cost No land needed Fastest installation Maintenance more difficult May have orientation problems Replacing or repairing the roof means removing and reinstalling the panels
• Ground mount – Expensive – Need significant land area – Very flexible for array arrangement and orientation – Easy to access for testing and maintenance – Panels remain cooler than on roof mount
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Niue School ~20 kWp (top roof mount) and Hospital ~31 kWp (bottom ground mount)
Mounting on Flat Roof (Chuuk (Chuuk))
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Panel orientation
• In most places, for the most kWh per year, tilt at about the latitude angle toward the equator. – Provides output that peaks fairly sharply between 11 and 12 noon. ~US$0.45 per kWh – Some places (such as Palau) have seasonal solar energy patterns that make the optimum tilt not equal to the latitude angle
Wiring
• Wire must be large enough to pass peak currents without significant voltage drop – Maximum energy loss of 2% is ok • Insulation must be able to withstand high temperatures, high levels of weather exposure and high levels of sunlight (UV) exposure as well as the voltage of the string. – Typically double insulated cable with the external insulation highly resistant to UV and high temperatures
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Inverter • Converts DC from panels to grid quality AC • Automatically disconnects if grid fails – Typically senses and disconnects due to Frequency variations Voltage variations Excessive rate of frequency variation Excessive rate of voltage variation Other parameters such as over temperature, over current, etc. • Reconnects automatically after sensing at least five minutes of normal grid operation and there are normal conditions in the inverter itself
Inverter Characteristics – Allowable input DC voltage varies with some models allowing less than 200V and others to over 1000V – Output voltage and frequency programmable – Most inverters can be easily paralleled or used in multi-phase configurations – Often installed with many paralleled inverter units in a rack or on a wall for larger systems – May include an isolation transformer or be direct connected
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Small Inverters
Inside one residential sized inverter (1.7 kW). Note the emergency DC disconnect handle at the bottom left and AC connection bottom right
Large Scale Inverter (over ~50 kW)
• Rack of paralleled inverters for larger scale PV Grid Connection
Fronius commercial inverter unit
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Bank of 100 kW inverters
Photo by SMA
3 Phase Multiple Inverter Installation
Wall of 1.7 kW inverters (6 in parallel for each phase) during wiring at the Niue hospital.
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Inverters for the Pacific Islands • Inverters should be sealed with no active components exposed to the air, only heat exchangers and the transformer.
– Absolutely avoid inverters with a cooling fan that blows ambient air onto the circuit board if it is to be installed where corrosion is a problem – most Pacific Islands.
DC Disconnects, Lightning, and Earthing
• Electrical codes for Australia, New Zealand and the US all require each string to have its own DC disconnect switch
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
• Lighting protection is optional but often installed – Lighting surge suppressors do wear out so must be monitored – Single earthing point for all components is required
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Lightning surge suppressors and DC disconnect switches for each string
System Circuit • Typical circuit for one inverter module – Multiple strings per inverter – Note two meters, one for the solar and one for the use by the client • More inverter strings equals more power
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Niue Hospital System
• 18 inverters (3 phase system) • 36 strings of five 170 Wp panels each (total 1.7kW per inverter, 30.6kWp of panels) • Ground mounting designed to resist category 5 cyclone • 200V nominal DC feed voltage • 3 phase feed-in at Hospital transformer
Maintenance
• Panels require very low maintenance and have a long life (20+ years). Most problems are with the packaging. – Clean when necessary (usually only if some object blows onto the panels, dirt and dust usually is not a problem) Should be cleaned at commissioning because manufacturing residue may remain on glass – String voltage and current should be checked for consistency between strings at least weekly through the data link to the inverter if one string is consistently low relative to the others, probably a connection or wiring problem exists
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Corrosion due to water entry
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Discoloration of material used for cell encapsulation
Delamination of cells from the glass cover
Inverter Failures • Inverter failures follow the “bathtub” curve: Most failures occur early (within 2 years) then maybe 10 years pass with very low failure rates then the failure rate starts to rise rapidly. • Prepare for 15% failures during the first couple of years by having spares in stock. • Monitor inverter outputs for consistency among inverters at least weekly and preferably every afternoon • Most inverter problems can only be fixed by replacement of the inverter with a spare. Local repair of most problems is impossible.
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Operational Maintenance The key to operational maintenance is the use of the data presentation capability of the inverters and associated data loggers for use with a computer (e.g. SMA’s ‘Webbox’). Every inverter and every string is constantly monitored and data made available to a laptop or networked computer for checks of operation and for initial troubleshooting. The output of any string or inverter that is seen to be significantly different from the others is a sign of a problem to be checked.
Other Maintenance
• Check the status of lightning arresters monthly (indicator color)
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
• Clean heat exchanger surfaces and check fan operation on inverters at least monthly • Examine panels at least annually for corrosion, delamination or discoloration and problems with mountings
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Warranties
• Panels (read the fine print!!!) – Physical problems 5 to 10 year warranty with panel replacement – Output warranty 20-25 years. Obligation is only to provide replacement of lost capacity Generally useless, mainly for PR purposes • Inverter – Typically 5 years with 10 years or more usually available at extra cost – Usually does not pay for shipping which can be expensive
Panels for Grid-Connected Solar PV Dr. Herbert A. Wade
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Grid Connected Solar PV Workshop Republic of Palau November 1-5,2010
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Solar Panels
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Photovoltaics • The term photovoltaics (PV) refers to the conversion of light energy (in this case light from the sun) to DC electricity. • The technology used today dates from the 1950s and became commercial in the 60’s when power for space craft was provided by solar photovoltaics • Today PV generation is by combinations of solar panels with size rated by the maximum Watts of electricity they can produce under a set of standard conditions
Solar Panel Power Rating • Panels are rated in Watts Peak (Wp). • This is the maximum number of Watts power that the panel should produce if: – it is exposed to 1000 W/m2 of sunlight – The sunlight is coming straight onto the panel – The panel is clean – There is a cell temperature of 25°C – The sunlight passes through an air mass of 1.5 (about a 45° angle above the horizon) – Power from the panel is delivered to the load at the maximum power point of the panel (the optimum loading)
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Actual Panel Output • Solar energy is almost never is great enough to provide 1000 W/m2 of solar radiation. Typically 800-900 W/m2 is the highest seen on clear days at noon. • In the tropics, solar cells are 50C to over 60C. Higher cell temperatures result in lowered output of 10% to 15% over rated values • Panels rarely face directly toward the sun, surface reflections increase and output decreases as a result • There is often a mismatch between the load and the panel resulting in a few percent reduction from the rated value.
Panel Types • Single Crystal construction. Each cell is a single crystal of silicon. This is the oldest design and provides the highest light to electricity conversion efficiency. Round cells are made initially but they may be cut square. Panel made up of many cells connected in series. Very reliable. • Polycrystalline construction. Each cell includes several large crystals of silicon. Cells can be any shape. Almost as high efficiency as single cells. Panel made up of many cells connected in series. Excellent reliability. • Thin film construction. Silicon or other PV material is put in a very thin layer onto metal or plastic. Mass production is relatively easy and theoretically can be cheaper than crystal based panels. Efficiency low to medium. Reliability varies from poor to good. Sometimes called “amorphous” panels.
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Panel appearances
Single crystal cell
Polycrystalline Cells Thin Film panel
Panel construction • Top layer is glass or in some cheap panels, clear plastic. • The middle layer is the active PV material. In the case of crystalline cells, many individual cells are connected in series to make a panel (sometimes called a “module”). Each cell produces about 0.5 to 0.6 volts. The area of the cell determines the Amperes it can produce with modern cells providing 5-8A under full sun conditions. • Backing for panels is typically a special plastic called Tedlar though sometimes glass. Thin film panels may have a backing that is ceramic or metal as well as possibly glass or plastic. • Cells are embedded in a clear plastic material between the top layer and the bottom layer. This is called the encapsulant and serves to help waterproof the panel and to reduce internal reflections that would lower panel efficiency.
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Panel construction
Typical solar PV panel construction cross section
Terminology
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Recommended Specifications • Panels – Must be able to be connected to provide an output appropriate to meet the input requirements of the inverter
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
– Screw type wire terminals with lock washers or polarized MC-4 plugs and cables – Monocrystalline or polycrystalline construction with glass cover and aluminum or stainless steel frame – Meet international standards for construction and are certified by testing at an international test center
Key Characteristics • Number of cells determines the output voltage • Voc = the open circuit voltage which is the voltage across the terminals with no load attached • Varies little with the amount of sun but falls as cell temperature goes up • 0.5V to 0.6V per cell • Isc = Short circuit current which is the Amperes measured directly across the terminals with no load attached • Varies directly with the amount of sun • Impp= Current delivered at the maximum power conditions under standard test conditions (STC) • Vmpp= Voltage delivered at the maximum power conditions under standard test conditions Note that Impp x Vmpp = Wp
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Voltage-Ampere Relationship
Drawing copyright GSES
Solar Level Affects Mainly Amperes
Drawing copyright GSES
Effect of changes in insolation on panel current and voltage
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
• Connecting panels in parallel (+ terminal of one panel connected to + terminal of the other and – terminal of one panel connected to – terminal of the other) results in adding the amperes produced by each panel. • Requires a junction box since cable plugs/sockets do not mate
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Connecting Panels • Connecting panels in series (+ terminal of one panel connected to – terminal of the next) results in adding the voltage of the series connected panels • Easy with plug and cable type connections. The positive connector and the negative connector mate
Increasing Array Voltage
Drawing copyright GSES
Panels can be connected in series to increase output voltage. A series connection will work well only if the panels have the same ampere rating.
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Ampere Rating of Panels • Ampere rating depends on the type and size of the cells. – Monocrystalline cells have slightly higher ampere output for the same size cell than polycrystalline cells – The surface area of the cell determines the amperes for any given type of cell • To match panels for Amperes if the Isc rating is not known, choose panels with the same size and type of cells.
Increasing Array Current
Drawing copyright GSES
To increase the amperes available, connect panels in parallel. As long as the two panels have the same voltage (the same number of cells) it will work ok
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Voltage Rating of Panels • Output voltage is determined by the number of cells connected in series on the panel and cell temperature. – To match voltages for panels, the two panels should have the same number of cells. It does not matter whether they are monocrystalline or polycrystalline, both have the same voltage of about 0.5V-0.6V per cell • Also rated according to the maximum voltage allowed between the cells and the frame – Typically 600V though some panels can handle over 1000 V
Sun’ Sun’s movements over the year
Drawing adapted from copyrighted drawing by GSES
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Proper Orientation • Facing toward the Equator (South in the North Pacific) - At low latitudes the direction of the tilt is not so critical • Tilted about the same number of degrees as the latitude of the site unless there are seasonal clouds then a steeper tilt may be needed for maximum output if maximum sun is during the time when the sun is furthest from the equator • Never tilt less than 5° because fast water runoff is necessary for cleaning. 10° to 15° of tilt is best
Shading
• Output from panels in the shade is a small fraction of the output from a panel in the sun • Even shading a few cells on the panel will greatly reduce the output from the panel • No shade should be on the panel from 0900 to 1500
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Shading on Small Panel Area • Shading on even one cell greatly reduces panel output
Drawing copyright GSES
The shaded cell acts as a resistor and absorbs power from the string
Seasonal Changes and Shade
Solar panels may be free of shade during part of the year and fully in the shade another time of the year
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Heat effects
• Every two or three degrees C (3.6° – 5.4° F) of temperature rise in a PV cell can lower the output of a PV panel by up to 1% due to lower voltage output. • Cell output is standardized at 25°C (77°F). Under full sun in the tropics the cell temperature may be 40°C (104°F) higher than ambient so panel output can fall as much as 20% over the Wp rating just due to temperature • Monocrystalline and polycrystalline panels lose much more power with increased temperature than thin film panels • Keep panels as cool as possible to prevent power loss due to overheating • NEVER mount solar panels flush on any surface, if at all possible provide 150 mm (6 inches) or more of ventilation space underneath panels, especially on metal roofs and never less than 60 mm (2.5 inches)
Temperature Effects – Crystalline Cells
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Spacing Under Panels for Ventilation
Panels mounted on rails to provide space for ventilation
Drawing copyright GSES
Crystalline panel voltage and current changes with temperature
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Panel Mounting for Best Output
• Face the equator and tilt to latitude or optimum clear sky sun inputs but tilt no less than 10 degrees • May need to take into consideration seasonal and diurnal solar energy patterns • Must have ventilating air passing underneath the panel • No shade any time of the year between 0900 and 1500
Mounting - continued
• Mounting must use marine grade stainless steel fasteners that isolate aluminum panel frames from the roof. No aluminum can be allowed to touch a steel roof • Mounting arrangement must be strong enough to survive storms yet simple enough to allow access to panel connections without major dismantling of the array
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Inverter Voltage and Ampere Inputs • Panels are arranged in series connected “strings” to reach a voltage appropriate to meet the input requirements of the inverter – Don’t forget the MPP voltage is what you must use when calculating string voltages for normal operation – Don’t forget to reduce the MPP voltage due to the cell temperature being higher than 25°C (77°F) • Strings can be paralleled to increase the current available to meet the power capacity of the inverter – Each string must have a separate disconnect
Typical Panels Used in the PICs • Type = Monocrystalline • Wp = 170 Watts • Voc = 43.3V • Isc = 5.0 A • Vmpp = 36.1V • Impp = 4.7 A • Voc temperature coefficient = -165mV/°C (- 91.7mV/°F)
Day 2
1
Grid-Connected Solar PV – Inverters and Strings Dr. Herbert A. Wade
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Grid Connected Solar PV Workshop Republic of Palau November 1-5,2010
Inverter Characteristics and Specifications
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
AntiAnti-Islanding • Islanding refers to the idea of a PV system generating power for input to the grid when the main grid supply is off – The creation of an “island” of power – Serious safety hazard if a PV system “islands” • Multiple redundant circuits prevent islanding – Voltage excursions beyond the acceptable range – Frequency excursions beyond the acceptable range – Rate of voltage change – Rate of frequency change – Effective loading
• Millions of grid connected inverters are in service and islanding has not been a problem Inverters must be certified for anti-islanding by an international certification body Never allow the use of uncertified inverters Where there are few installations in service, utilities that are not familiar with the exemplary safety record for certified inverters may choose to manually disconnect PV systems from the grid when the grid is going to be serviced.
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
General Types of Inverter Installations • Single large inverter for the entire installation – May be single phase or three phase – Often custom made and not locally maintainable – Common in Japan and the USA • Multiple smaller inverters connected in parallel – Rapidly becoming the international standard Common in Europe – One inverter fails and only a part of the output is lost – Spare parts are not expensive and are easily stocked for quick replacement – Maintenance does not require special skills or training for the specific type of inverter being used – Slightly higher overall cost than a single large inverter but the life cycle cost is lower for the Pacific Islands due to the cost of repair and shipping for single large inverters
Inverters Chosen for NDBP in Palau SMA Sunny Boy 3000US
Utilities that follow USA power standards must be sure to buy inverters that follow US power standards and US solar standards. Most non US made inverters can be programmed to fit US standards but May have peculiarities that make the grid connection difficult for residences.
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Primary Specifications • DC input voltage range – Rarely below 100V and may go as high as 1000V The number of panels in a string must be sufficient for the MPP string output voltage to never go below the minimum for the inverter after voltage reduction due to temperature is considered. The number of panels in a string must not exceed the number needed to reach the maximum MPP allowable voltage for the inverter before voltage reduction due to temperature is considered.
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Power Rating
• Output Power – Maximum output and input Watts
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Allowable DC input Wp of panels is typically somewhat higher than the maximum AC output power rating Wp ratings of panels are always substantially higher than what is actually observed in practice
Efficiency
• Efficiency in percent equals: (Watts out/Watts In) X 100
Over the useful output range of modern inverters efficiency may range from about 85% to 98%
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Transformer type inverter
• Grid isolation using an inverter with a transformer – Transformer included
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fully isolates DC from AC Safest and least likely for seeing an unwanted mix DC and AC power Adds some cost, slightly lowers efficiency, heavy Does not have to be grounded but can be if the circuitry requires it
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Transformerless Inverters – Semiconductor based isolation of the grid and the solar array No transformer and no electrical isolation between DC and AC sides Possible for AC grid power to feed back to the DC side under rare modes of failure Possible for DC power to feed to the grid under some circumstances Cheaper, higher conversion efficiency, light in weight Must be grounded
Inputs from the PV Array • Number of string inputs – Each string input has its own MPPT device and DC inputs are not mixed • DC disconnects that can isolate the inverter from the solar strings may be in the inverter or separate – Must use DC switches or circuit breakers rated for 1.25 times the string maximum voltage (number of panels times Voc of one panel)
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Arcing • Small arcs are seen when switching an AC circuit with the arc bigger with higher voltages and amperes – AC arcs are generally self-extinguishing because with AC the voltage reverses polarity twice for every cycle (120 times per second for 60Hz power, 100 times per second for 50 Hz power) • DC arcs flow only in one direction and are not selfextinguishing. They also become bigger as the voltage and amperes increase. – When a DC spark occurs due to switching a DC load or power supply on and off, the resulting spark heats the air and ionizes it making a low resistance path through the air. This makes the arc even bigger and can extend much farther than an AC arc
Connecting and Disconnecting the PV • The power from the PV array is DC at voltages high enough to sustain a long, very hot arc – Fires can be started and switch or contacts melted or ruined due to the arc that forms when the contact is broken – To avoid arcing, special DC switches, circuit breakers and other load disconnecting devices must be used. NEVER use an AC circuit breaker as an array string disconnect
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Arcing at the NDBP inverter (slow motion)
Do not try this at home……
AC Disconnect • AC disconnects may in the inverter or separate – May be a standard circuit breaker at least 25% higher in capacity than the maximum Amperes that the inverter can deliver to the grid – Should be lockable (switch or the box cover) for safety purpose – Should be located near the inverter for safety and convenience of maintenance (the utility may require a second disconnect at the meter)
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Inverter Data Access • Data delivery mechanism – Usually data is through a LAN type cable with a standard computer interface May be included in the inverter or may require an additional plug in card to be inserted in the inverter Unless there is a data logger attached (e.g. the SMA “Webbox”) or there is a computer dedicated to collecting inverter data connected to the data line, only recent data will be available
Data Available from the Inverter • Most quality inverters make available at least – Date and time of data packet – Amperes coming from each PV string – Voltage at each string – AC Watts or VA from the Inverter – kWh delivered to the grid since installation – Status of the inverter (standby, off line, delivering power to the grid, etc.) – Any error conditions that currently exist • Other data that may be available may include – Heatsink temperature – Fan operation – Time and date of last restart
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Harmonic Distortion
• The presence of frequencies that are a multiple of the utility frequency present in the AC output – Less than 5% is reasonable for modern inverters – Most utility grids already have more than 5% harmonic distortion in their power delivered to customers
String Design Procedures • Determine the maximum cell temperature – Usually occurs at the time of maximum solar input combined with high air temperature so it is usually the middle of the day and early afternoon – If actual measurements are not available, assume 65°C (150°F) which is 40°C (104°F) above the standard 25°C (77°F) temperature – Can use an infra-red thermometer for measurement • Determine the minimum cell temperature (the same as the minimum air temperature since that occurs just before sunrise) – If actual data are not available assume 19°C (66°F)
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
• Determine the maximum possible voltage from one panel – Will equal the Voc that occurs at sun-rise since that is when the cells are coldest (for the sample panels that is 43.3V Will occur at the lowest cell temperature when sun is shining on the panel – Determine the adjustment in voltage needed for the minimum temperature (19°C an be assumed) For our panels, each °C the temperature is different from 25°C, the voltage will change 0.165V. 19°C is 6°C colder than 25°C so the voltage will rise by 0.165 x 6 = 0.99V. So for our panels the maximum Voc will be: 43.3V + 0.99V = 44.29V
Maximum Panels in a String
• Determine the maximum number of panels that can be put in series without exceeding the maximum input voltage of the inverter – Our sample inverter has a 500V maximum voltage input • Divide the maximum inverter voltage by the maximum Voc of one panel and you get the maximum number of panels that can be in a string – For our case that will be 500V / 44.29V = 11.29 or in a practical sense 11 panels maximum in a string (round the result of the division down to the nearest whole number)
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Minimum Panels in a String • Determine the minimum number of panels that can be in a string and still keep the inverter producing power: – Assume the maximum cell temperature and therefore the minimum output voltage – At our assumed 65°C cell temperature there is a 40°C higher temperature than the standard 25°C • Determine the adjustment in voltage for temperature by multiplying the voltage change per °C times the number of °C the cell is hotter than 25°C – For our case that is 40°C x -0.165V/°C = -6.6V – So the Vmpp minimum per panel will be 36.1 – 6.6 = 29.5V – Assume a 2% voltage drop in the wires = 29.5V x .02 = ..0.59V – Minimum V at the inverter = 29.5V – 0.59V = 28.91V • Divide the minimum input voltage for the inverter by the minimum Vmpp per panel to get the minimum number of panels – In our case that is 200V / 28.91V = 6.92 (7) panels (round the result of the division UP to the next whole number)
Determining Maximum Power Point Conditions
• MPP conditions will be providing the most energy to the grid. • Determine the maximum Vmpp of one panel – Vmpp + adjustment in voltage for minimum °C – For our panels 36.1V + 0.99V = 37.09V • Divide the maximum MPP input voltage (400 V for our sample inverter) by the maximum volts per panel – For our components that will be 400 V / 37.09 V = 10.78 (10) panels (round the number from the result of the division down to the nearest whole number)
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Summary of Values • Choose the smaller of the number of panels for maximum Vmpp or Voc – In our case maximum Vmpp value is 10 panels. For maximum Voc it is 11 panels so we choose 10 panels as the maximum for a string • Choose the number of panels for minimum Vmpp – In our case that is 7 panels. • The number of panels in a string should have no less than 7 strings or the inverter will cease producing power at low sun. A string can have no more than 10 panels or the MPPT unit will not work at maximum sun and optimal power will not be produced.
String Design for the Sample Equipment • 10 panels per string • Maximum MPP voltage at 19°C = 370.1V – Acceptable, maximum string MPP voltage = 400 • Minimum MPP voltage at 65°C = 295V – Acceptable, minimum string MPP voltage = 200V • Maximum Voc at 19°C = 442V – Acceptable, maximum string Voc = 500V • So our 10 panel string will provide efficient inverter power at all site conditions
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Paralleling Strings • Additional Amperes can be obtained by putting strings in parallel however there are some added requirements: – Each string has to have its own DC disconnect This allows testing of an individual string Provides a means of isolating that string so repairs can be made – Each string must be protected from receiving excess current from other paralleled strings that may cause damage Usually in the form of a fuse that is rated below the maximum current allowed to flow through the panel from external sources Called the reverse current rating or maximum series fuse rating Fuse must be of a type acceptable for DC use
Fusing of Strings in Parallel
The sample panel (or string of sample panels) is rated for a maximum of 15A reverse current (maximum series fuse rating) and an Isc of 5A So with each panel (or string) capable of putting out 5.5A, up to three panels (or strings) can be connected in parallel without concern for damage to a shaded or nonfunctioning panel. With four or more in parallel, fuses on each panel (or string) of 15A will be required
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Layout of Panel Wiring • To minimize damaging voltage surges caused by nearby lightning strikes, string wiring must not include any open loops CORRECT
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
INCORRECT
6 panel string wired with an open loop
6 panel string wired to minimize lightning induced voltage surges
Balance of System Components • Besides the panels and inverter, additional components are needed to comply with safety and operational requirements: – A DC disconnect for each string Whether strings go directly to the inverter or are paralleled with other strings, each string requires its own DC disconnect
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Overall Design for a Residence (3.4 kWp) • One SMA SB3000US inverter • Two strings of 10 – 170 Wp monocrystalline panels – Each feeding a separate inverter input
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
• Two DC disconnects (one for each string) • One AC disconnect near the inverter – The utility may require an additional one near the meter
Power Requirement • Each panel is 170Wp in size but derated due to high temperature (which occurs at peak solar input) to: 29.5Vmpp x 4.7Ampp = 138.65 Wp • Each string input allows for 1875 Watts input • So at mid-day the maximum input power from the 10 panel string = 10 x 138.65 = 1386.5Wp – Proposed design is within an acceptable power range
• 10 panels • SMA Sunny Boy 3000US inverter • Watts = 1700 Wp • Maximum DC Volts = 442 (at 19°C) • DC Amperes = 4.7A
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Sample Basic Residential System
System Possibilities with one inverter • SMA SB3000US inverter with 2 string inputs • System can have as few as 7 panels per string so the range of rated powers possible with that sample inverter and the sample 170Wp panels will be: 7 x 170 = 1190 Wp (one string min volts) to 20 x 170 = 3400 Wp (two strings max volts)
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Output Estimation • The output from a grid connected installation can be estimated using average annual solar energy data for the site – Accuracy is ±15% or so because of the variability of solar energy at a specific site from year to year • Calculation of the annual system output must include: – Average solar energy available at the site at the orientation of the solar array Most solar data is measured on a horizontal surface, that must be converted to the energy that is received on the tilted surface of the solar panels NASA provides information for conversion of horizontal to tilted surfaces at: http://eosweb.larc.nasa.gov/cgibin/sse/sse.cgi?+s01#s01
Input estimation
Energy = kW x hours = kWh Area under the blue curve = kWh from the sun on a 1 m2 surface Convert that area to a rectangular area with 1000 W/m2 as the top The width of the rectangle = “peak sun hours” or the hours that the sun would have to shine at 1000 W/m2 to provide the same energy as it actually did over the day. That will be the same number as the value measured by a solarimeter. So if the measurement is 5.1 kW/m2/day that means a “peak sun hours” of 5.1 hours per day
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Panel Output Estimation • Panels have their Wp rating at 1000 W/m2 so multiplying the Wp rating times “peak sun hours at 1000 W/m2 gives the output from the panel over the day in Wh at STC • To get the real output from the panel, adjustments have to be made because the panel is not actually at STC. Typical values would be: – Temperature = -15% = 85% left – Orientation error = -5% = 90% left – Surface reflections = -7% = 93% left – Dirt = 3% = 97% left – Shading = 0% = 100% left • Total correction to STC values = .85x.90x.93x.97x1.0 = .69 – Actual output = Wp x Peak hours x .69 • So for a 170 Wp panel in a place with 5.1 kWh/m2/day of solar the actual output will be about 170 x 5.1 x .69 = 598 Wh/day
Adjustment for System Losses • Additional losses that need to be considered have typical values of: – Wiring loss = 2% = 98% left – Inverter loss = 8% = 92% left • Total additional adjustment = .98 x .92 = .90 • So the output from the system can be estimated at: – Output from the panels x system loss factor – For the 170 Wp panel in the 5.1kWh/m2/day solar environment = 598 Wh/day x .9 = 538 Wh/day or – 538 x 365 = 196,370 Wh/year = 196.4 kWh/year
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Simplified System Output Estimate • A reasonable estimate of the daily output from an unshaded grid-connected PV system within about 10° of the equator will be: Wp of panel x kWh/m2/day of solar x 0.62
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Where 0.62 = 0.69 x 0.90 or the total system loss factor Since the solar input varies considerably from year to year, this simplified estimate will be adequate as it will fall within the range of values that will actually be seen
Additional Corrections to Apply • The assumption for the simplified estimation formula includes panels oriented toward the equator and tilted at about 10° and the site being within 10° of the equator. For installations with large errors in orientation or with some shading over the day, additional corrections will need to be made to the estimate. • The effect of orientation error increases as distance from the equator increases so higher latitude sites will be more affected by the roof not pointing its slope toward the equator
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Shading • Shading of any kind causes serious reduction in panel output at the time of day that the shading occurs. If the shading occurs before 0800 or after 1600 it will not cause more than 10% output reduction but the reduction increases rapidly as the shade time gets closer to midday – Small areas of shade can reduce panel output much more than the small area would imply. Even a mast to hold up a TV antenna that shades a small part of the PV array can reduce the array output 20% or more. Some remote telecom installations have not worked well because the solar panels are mounted so that sometimes they are shaded by the mast holding the telecom antenna
Installing Grid-Connected Solar PV Dr. Herbert A. Wade
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Grid Connected Solar PV Workshop Republic of Palau November 1-5,2010
Sample Residential System • To illustrate installation of a grid-connect PV system, a simple residential installation that was installed on the Small Business Development Center will be used as the example. The installation has as its characteristics: – 10 panels in one string, 170 Wp per panel – SMA SB3000US inverter with attached DC disconnect – AC disconnect with standard AC two pole circuit breaker – Single phase output to a 240V 60 Hz grid connection with central neutral/ground (120V each side of ground) – SMA “Webbox” data logger – SMA “Sensor Box” for solar radiation and cell temperature measurement
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
The Building at 0845 on a Clear Day
The roof peak runs NW-SE and the slope is about 15°. Wood truss roof structure with enameled steel roofing. No shade between 08001700 except for light pole to the west and a power entry mast on the east.
Choice of Roof side • The maximum sun over the year falls on a south facing roof. The maximum output from the panels will occur when the temperature is lowest. – Morning will be when the panel temperature is lowest so facing the panels on the NE roof would provide higher efficiency of energy conversion – The most energy will fall over the year on the SW roof because of the sun being lower in the south sky during the dry season when there is high sun input – There is a light pole on the western side that may cause afternoon shade on some panels some part of the year • So both roofs have advantages. In this case the choice of the east roof was made partly because the output reducing effect of high afternoon temperature will be high in this environment and partly because of the shading that may be introduced by the light pole on the western side of the roof
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Laying Out Panel Rails • Panels were kept as close to the south end of the roof as possible to avoid any shade from the central power entry mast • Panels were mounted as close to the ridge as possible to reduce the possibility of leaks and reduce the possible morning shade from trees to the east
Lay the rails on the roof to better visualize any layout problems or Possible shading.
Laying out the Inverter Installation • It is convenient for repair and troubleshooting to have the inverter near the grid connection. In this case the AC disconnect, DC disconnect and Inverter could be mounted side by side
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Inverter, DC & AC Disconnects, Meters
Mounting Panels
• After rails are screwed to the roof, panels are clamped in place on the rails. In this case, two rows of five was the best layout to avoid shade and for wiring to the inverter
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
On the Roof Mounting Panels
• Teamwork
Clamping Panels to Rails
• Mounting the junction boxes (for + and − to DC disconnect
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Wiring the String to the Inverter
Wiring the String to the Inverter • Wiring to the inverter with + connection in one junction box. A − junction box is at the other end of the string with its wire going around the string to go through the + junction box but with no connection in the box. The − wire goes through the + box just to enter the conduit to the inverter
• The sensor box should be mounted on the same slope as the panels so the solar measurement shows the amount actually falling on the panels. Glue the cell temperature sensor to the back of one panel. Do not cut or extend the temperature sensor wire, it is special wire. The data line goes down the same conduit as the wires to the inverter from the string.
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Mount the Sensor Box
Attach Frame Ground Wires and Tie Up Wires off the Roof • Attach ground wire to rails using stainless steel or copper hardware. Tie up all panel wiring to rails so none touches the roof. Run ground wire through the main conduit.
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Finished on the Roof
Wire AC and DC disconnects and Ground
• Check the voltage and polarity of the DC wires from the string. If the polarity is wrong, disconnect the panel wire on the roof and switch the wires in the disconnect then reconnect and check again. If voltage is wrong, there is an error wiring the panels.
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Connect the Final Panel Connection
Turn it On and Check for Operation
Turn on AC Disconnect, Turn on DC Disconnect and look for errors as the Inverter starts up. In this case, no errors and the system is running
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Install and Wire the Data Logging Unit
Inverter Installation Complete and Running
Day 3
1
SHS, Mini grid (PV mini grid)
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Grid Connected Solar PV Workshop Palau November 1-5,2010
Type of power system Interconnection to Main Grid: Off, On (1) Solar Home System PV
PV
PV
(Capacity: 50W ) Install a renewable energy system in each household separately This system is applied mainly for a non-electrified region or a rural area.
(2) Mini grid system DG DG
(3) Normal grid power system Main Grid ( > 500kW )
G
(Capacity:10 to 500kW ) Install a renewable energy system in a small community, sometimes combined with diesel generators. In case of combined system, it can save diesel fuel consumption and enhance power supply.
Off
(Capacity: > 500kW ) Install a renewable energy system to the main grid.
On
2
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Off Grid: Solar Home System (SHS) No
Title
(1)
SHS
(2)
(3)
Mini grid
Grid connected Large PV system & Hybrid system
Sub-t.itle
Main Grid connection
Supplied power
Gen Size (approx.)
Genset
Other RNE
Battery system
Note
DC SHS
Off
DC
< 1kW
No
No
Yes
AC SHS
Off
AC
< 1kW
No
No
Yes
PV Mini grid
Off
AC
1 - 50kW
No
No
Yes
50 to 600 Households Battery charge station
PV hybrid systems within mini-grid
Off
AC
10 - 500kW
Optional (a few hours per day)
Wind biomass micro-hydro etc.
Optional
New components
Grid connected large PV system
On
AC
> 40kW
No
No
Optional
With reliable grid (24H supply)
Grid connected hybrid system
On
AC
> 100kW
Basically No. Optional (a few hours per day)
Wind biomass micro-hydro etc.
Optional
With reliable grid (24H supply)
3
Example of SHS (solar home system) Solar array Solar array Solar array
Controller Light Solar array Storage battery 4
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Off Grid: DC and AC supply system No
Title
(1)
SHS
(2)
(3)
Mini grid
Grid connected Large PV system & Hybrid system
Sub-t.itle
Main Grid connection
Supplied power
Gen Size (approx.)
Genset
Other RNE
Battery system
Note
DC SHS
Off
DC
< 1kW
No
No
Yes
AC SHS
Off
AC
< 1kW
No
No
Yes
PV Mini grid
Off
AC
1 - 50kW
No
No
Yes
50 to 600 Households Battery charge station
PV hybrid systems within mini-grid
Off
AC
10 - 500kW
Optional (a few hours per day)
Wind biomass micro-hydro etc.
Optional
New components
Grid connected large PV system
On
AC
> 40kW
No
No
Optional
With reliable grid (24H supply)
Grid connected hybrid system
On
AC
> 100kW
Basically No. Optional (a few hours per day)
Wind biomass micro-hydro etc.
Optional
With reliable grid (24H supply)
5
DC and AC supply system (PV system) 50 – 70 W Solar Home System(SHS) Module
DC 12V
Battery BatteryController Controller (DC) (DC)
DC 12V
For every household e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Battery Battery
1 to 50 kW Stationary PV system
Array For Community
DC 300V
Power PowerConditioner Conditioner (DC (DC-> ->AC) AC)
AC 200V
Battery Battery 6
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Feature of DC and AC supply system Supplied power
Characteristics
Disadvantages
DC
Connection of sources and loads via DC distribution line
• Main energy sources connected on DC bus • Charger are needed for different energy sources • For illumination and DC loads • Short distance between components
• Expensive DC installation • Poorly expandable • Not easy to find standard products
AC
Connection of sources and loads via AC distribution line
• Free selection of energy • Necessity of Inverters sources (standard grid components) • Long distances between components • Simple extendibility, futureproof
7
Off Grid: PV mini grid No
Title
(1)
SHS
(2)
(3)
Mini grid
Grid connected Large PV system & Hybrid system
Sub-t.itle
Main Grid connection
Supplied power
Gen Size (approx.)
Genset
Other RNE
Battery system
Note
DC SHS
Off
DC
< 1kW
No
No
Yes
AC SHS
Off
AC
< 1kW
No
No
Yes
PV Mini grid
Off
AC
1 - 50kW
No
No
Yes
50 to 600 Households Battery charge station
PV hybrid systems within mini-grid
Off
AC
10 - 500kW
Optional (a few hours per day)
Wind biomass micro-hydro etc.
Optional
New components
Grid connected large PV system
On
AC
> 40kW
No
No
Optional
With reliable grid (24H supply)
Grid connected hybrid system
On
AC
> 100kW
Basically No. Optional (a few hours per day)
Wind biomass micro-hydro etc.
Optional
With reliable grid (24H supply)
8
Advantage
Disadvantage
1.Clean generation system
1.Generation depends on sunshine duration.
2.No moving and high temp/pressure parts, possible automatic/unattended operation and easy maintenance
2.Need wide footprint for large output because of low energy density
3.Non-depletion energy
3.Still high cost under the present situation
4.Possible mass production because of modular structure
4. DC output (can be advantage in some case)
5.Free and easy design from small to large scale in accordance as needed, and small limitation on installing Source: ANRE, NEDO
9
Off Grid: PV mini grid: PV output and demand
3kW PV output and household demand (in Japan) 2
150
1.5 100 1 50 0.5
0
1
3 5 7 9 11 13 15 17 19 21 23
Countrywide demand (GWh)
Household demand (kWh)
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Off Grid: PV mini grid: Features of PV system
0 Source: METI
10
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Off Grid: PV mini grid: System configuration PV panel (≅ 50 kWp)
For a community that is not too scattered. Usually 50 to 600 households.
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Inverter
Isolated, AC supply, no genset PCS Battery
Delivers the power to the households and common equipments through a grid 11
Off Grid: PV mini grid: System configuration Peripheral equipments Junction box Distribution board
PV array Inverter Insulation transformer Protection system
Power receiving panel kWh meter
PV mounting structure
Battery system Battery Charger
Load
Others Measuring instrument Display unit
12
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Off Grid: PV mini grid: Examples
Source: GTZ-ZSW
Installed in 2003 at Suohourima, Qinghai, China by GTZ 70 km from the next electricity line Between 300 and 400 households Old Diesel generator set is no longer in operation. Electricity is delivered according to energy availability (not for 24/24 hours) 13
Off Grid: PV mini grid: Examples PVgenerator
40 kW, 26 parallel strings with 18 modules, 85 W per module, manufacturer Qinghai Gaofai, cells from Astropower, US
Charge controller
13 channels, μC-controlled, sub arrays are switched off at the end of charge voltage of the battery, manufacturer Hefei Sunlight Power
Battery
Sealed (AGM) lead acid battery, cells 2 V/1300 Ah, 3 parallel strings with 110 cells, 858 kWh, manufacturer Enersys Huada Solar
Inverters
PWM with transformer and μC-control, 220 VDC/220 VAC, 1 inverter with 16 kW, 1 inverter with 24 kW, manufacturer Hefei Sunlight Power
AC Distribution
2 isolated and not grounded single phase grids supply different parts of the township. The single households have electronic energy Meters
Households All electrified households have electric light (fluorescent lamps (9W) or incandescent lamps (40W)), 90 % of the households have colour TV + satellite receiver + DVD player, and chest freezer to store meat, more and more households have electric heating blankets and pillows, some have washing machines (for external hot water supply) Source: GTZ-ZSW
14
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Off Grid: PV mini grid: Examples
Source: GTZ-ZSW
15
Off Grid: PV mini grid: Design procedure • • •
•
•
Significance Concept Feasibility study – Generation – Distribution – Demand forecast and dispatching – Environmental assessment – Economical evaluation Design – System configuration – Design – Regulation – Specification of components – How to select – Installation O&M
16
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Off Grid: PV mini grid: Planning & design System, equip. spec., supplier, capacity, supply characteristics, reliability, cost and so on.
Survey of various REN Concept design of the system
Demand characteristics, energy cost, electricity tariff
Investigation of target site
REN main unit, inverter, grid connection, battery, env. measure
Determination of equipment spec. Estimate supplied power and energy
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Estimate project cost Generation cost, distribution cost, cash flow
Determine operation pattern Estimate maintenance cost Estimate total running cost Analyze cost/benefit
Effect on environmental protection Effect on energy conservation
Implementation 17
Off Grid: PV mini grid: Check list on planning (1) • Concept and purpose – For what? Purposed should be shared among concerned parties. – Where? In existing facility or not? Exact location. – What load? Characteristics and size of load. Enough space for installed equipment? – Which system? Isolated or grid-connected? With battery or not? – When and how much? Construction schedule and cost. Can it be available? 18
• Project team – – – –
Establish team and assign project manager How to select the designer? What is bidding strategy of construction work? How can we maintain and manage the system?
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Off Grid: PV mini grid: Check list on planning (2)
19
Off Grid: PV mini grid: Check list on planning (3) • Site survey – Ambient environment Any obstacles to receive sunlight? Shadow of building, tree, mountain, stack, utility pole, steel tower, sign board and so on. Effect of fallen leaves and sand dust, snow cover (depth and frequency)
Salt and/or lightning damage, wind condition – collect all the possible obstacles
– Installed site Shape, width, direction, drainage, condition of foundation, volume of construction work, carry-in route, Waterproof of the building, effect on landscape
– Electrical facility Existing diagram and plot plan, space availability, wiring route and space carry-in route
20
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Off Grid: PV mini grid: Check list on planning (4) • Preliminary consultation – Local authority – Construction work, fire department, necessity of permission – Available subsidy – Information collection from expert/consultants
• Concept check – Is it firm concept? Site, load, system size and configuration – Is schedule fixed? – Is budget made based on expected generation output and its cost? 21
Off Grid: PV mini grid: Check list on design • Reconfirmation of design condition – Firm policy? – For what? Where? How big? How is the system? When? How much? – Constraints – Ambient environment, Site condition, existing electrical equipment, regulation, necessary procedure • Design – Direction and angle of PV panel – maximize output under the given condition – Array configuration and its installation – Foundation, mounting frame, waterproof, intensity calculation – Material, antirust and anti-corrosion of mounting frame material – Compliance with regulation – In accordance with the project purpose – Established schedule, expected result and project cost. • Application – Subsidy – Application for local authority • Design check – Fixed detail design, budget, construction schedule? – Finish all the necessary application? – Completed adequate bidding? 22
• • • • •
Estimate daily load curve Daytime: PV for load and battery charge Nighttime: Battery discharge for load Investigate charge/discharge time Calculate required PV and battery capacity
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Off Grid: PV mini grid: Design of operation pattern
Wee hours
Daytime
Nighttime
AM Supply from PV
PM Charge to battery
Supply from battery
23
Off Grid: PV mini grid: Calculation of PV array output • First, estimated the total size of load EL • Array output PAS: EL * D * R (HA / GS) * K
EL : Average load size (consumed energy kWh / duration) D : Load’s dependency rate on solar energy HA: Amount of solar radiation during a given interval [kWh/m2 * day] GS: Intensity of solar radiation at normal condition [kW/m2] R : Design margin ratio K : of integrated design factor(0.65 – 0.8, loss and equipment variation)
Array
Glass
Packing
Module Cell Backside film Bracket
Cell
Filling 24
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Off Grid: PV mini grid: Necessary components • Junction box – MCCB for PV array – Back-flow prevention device for each string – Main CB – Lightning protection/Arrester – Terminal block – Box PV array Junction box • Distribution board • Wh meter • Battery
From PV array
Lightning protection Reverse flow protection
P1 N1
P N
To inverter
Main CB P2 N2
Pn Nn
25
Off Grid: PV mini grid: Battery capacity • Lifetime of battery heavily depends on Depth Of Discharge (DOD), number of discharge and ambient temperature. • In application with PV, set the average DOD because of fluctuating charging/discharging energy by weather. • Key point – Estimate accurate load size – Optimize PV capacity, battery capacity and operational parameter of PCS • Procedure – – – –
Decide DC input power necessary for load Understand inverter input power Acquire amount of solar radiation at the site Set number of days without sunshine based on solar radiation condition and importance of load – Set DOD from expected lifetime of battery – Even in month with min solar radiation, determine capacity and angle of PV array to make charging energy cover discharge for load. – Calculate battery capacity Daily power consumption * number of days without sunshine Maintenance factor * DOD * Final voltage in discharge 26
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Off Grid: PV mini grid: Operation & maintenance
• • • •
Load forecasting is most important. Aim to full utilize PV power. Reserve battery energy for emergency case. Adjust charge/discharge energy in accordance with varying load.
Wee hours
Daytime AM
Supply from PV
Nighttime PM
Charge to battery
Supply from battery
27
Off Grid: PV mini grid: Battery charging station (optional)
BCS at suburb of Phnom Penh, Cambodia
28
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Off Grid: PV mini grid: Battery charging station (optional) Kanchanaburi Province, Thailand: 1992-1997 Budget: 316 million yen
The Sunlight made Nighttime Pleasant!
Battery-Charging Station
A fully charged battery provides lighting for a week Source: NEDO
29
Off Grid: PV mini grid: Battery charging station (optional)
Battery-Charging Station Source: NEDO
Using a charged battery at home 30
Mini grid (PV hybrid systems within mini grid)
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Grid Connected Solar PV Workshop Palau November 1-5,2010
Off Grid: PV mini grid No
Title
(1)
SHS
(2)
(3)
Mini grid
Grid connected Large PV system & Hybrid system
Sub-t.itle
Main Grid connection
Supplied power
Gen Size (approx.)
Genset
Other RNE
Battery system
Note
DC SHS
Off
DC
< 1kW
No
No
Yes
AC SHS
Off
AC
< 1kW
No
No
Yes
PV Mini grid
Off
AC
1 - 50kW
No
No
Yes
50 to 600 Households Battery charge station
PV hybrid systems within mini-grid
Off
AC
10 - 500kW
Optional (a few hours per day)
Wind biomass micro-hydro etc.
Optional
New components
Grid connected large PV system
On
AC
> 40kW
No
No
Optional
With reliable grid (24H supply)
Grid connected hybrid system
On
AC
> 100kW
Basically No. Optional (a few hours per day)
Wind biomass micro-hydro etc.
Optional
With reliable grid (24H supply)
2
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Off Grid: PV hybrid systems within mini-grid: System configuration
Wind
PV panel
Biomass
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Micro-hydro
Inverter Genset (runs for only a few hours per day)
PCS
Battery
Isolated, low voltage AC distribution systems
For a village (10 – 500kW)
Delivers the power to the households and common equipments through a grid 3
Off Grid: PV hybrid systems within minimini-grid: Examples (1)
Installed in 2004 at Noyon, Mongolia by NEDO (Sharp) 3 phase AC for school, hospital, government office and residential houses 200kW PV, 2 * 1,000Ah battery, 3 * 100kW gensets To realize suitable load dispatching for 3 gensets Source: NEDO
4
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Off Grid: PV hybrid systems within minimini-grid: Examples (1) Power center 100kW PC SL1
Generation 28,477kWh Charging 5,796kWh
Diesel generator #1 - #3
Generation 19,009kWh
Battery #1 PC SL2
Battery #2
Generation 28,850kWh Charging 4,318kWh
Hospital 40kW
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
PC SL3
Wee hours Generation 7,274kWh School 40kW PC SL5
Total power supply 95,299kWh
Daytime
Nighttime
AM
PM
Supply from PV
Charge to battery
Supply from genset
Supply from battery
Generation 7,176kWh Sum center 10kW
PC SL6
Operation pattern
Generation 2,570kWh Communication center 10kW
PC SL4
Source: NEDO Generation 2,091kWh
5
Off Grid: PV hybrid systems within minimini-grid: Examples (1)
• Key point in Operation – Rational use of generated power Awareness of energy conservation Use of high energy efficiency appliances – Reasonable tariff system Avoid no charge and/or fixed price Charge it on consumed energy – Fairness on charge collection system – Development/improvement of distribution system Source: NEDO
6
Installed in 2006 at Udomsai, Lao by NEDO (TEPCO+IEEJ) 200V AC for 10 villages (approx 900 houses, 5,000 peoples) 100kW PV, 80kW micro-hydro, 8 * 7.5kW pumps Instead of battery, use pumped storage system
Source: NEDO
7
Off Grid: PV hybrid systems within minimini-grid: Examples (2) System configuration
Transformer
10 Villages, 900 households, 5,000 peoples
Upper dam
PV array (100kW) Dummy load governor
Upper reservoir Spillway
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Off Grid: PV hybrid systems within minimini-grid: Examples (2)
Lifting pump (7.5kW * 8 )
Mini hydro (80kW) Lower reservoir
Source: NEDO
8
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Off Grid: PV hybrid systems within minimini-grid: Examples (2) Operation Pattern 1 Pump up at daytime, generation by mini-hydro at nighttime
Pattern 3 Pattern 2 + pump up at light load hours in night
pattern Pattern 2 Pattern 1 + generation by river-in-flow
Pattern 4 Load dispatching by PV and mini-hydro
Source: NEDO
9
Off Grid: PV hybrid systems within minimini-grid: Planning & design System, equip. spec., supplier, capacity, supply characteristics, reliability, cost and so on.
Survey of various REN Concept design of the system
Demand characteristics, energy cost, electricity tariff REN main unit, inverter, grid connection, battery, env. measure
Investigation of target site Determination of equipment spec.
Estimate supplied power and energy
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Estimate project cost Generation cost, distribution cost, cash flow
Determine operation pattern Estimate maintenance cost Estimate total running cost Analyze cost/benefit
Effect on environmental protection Effect on energy conservation
Implementation 10
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Off Grid: PV hybrid systems within minimini-grid: Check list on planning (1)
• Concept and purpose – For what? Purposed should be shared among concerned parties. – Where? In existing facility or not? Exact location. – What load? Characteristics and size of load. Enough space for installed equipment? – Which system? Isolated or grid-connected? With battery or not? – When and how much? Construction schedule and cost. Can it be available? 11
Off Grid: PV hybrid systems within minimini-grid: Check list on planning (2)
• Project team – – – –
Establish team and assign project manager How to select the designer? What is bidding strategy of construction work? How can we maintain and manage the system?
12
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Off Grid: PV hybrid systems within minimini-grid: Check list on planning (3)
• Site survey – Ambient environment Any obstacles to receive energy resources? Shadow of building, tree, mountain, stack, utility pole, steel tower, sign board and so on. Effect of fallen leaves and sand dust, snow cover (depth and frequency)
Salt and/or lightning damage, wind condition – collect all the possible obstacles
– Installed site Shape, width, direction, drainage, condition of foundation, volume of construction work, carry-in route, Waterproof of the building, effect on landscape
– Electrical facility Existing diagram and plot plan, space availability, wiring route and space carry-in route
13
Off Grid: PV hybrid systems within minimini-grid: Check list on planning (4)
• Preliminary consultation – Local authority – Construction work, fire department, necessity of permission – Available subsidy – Information collection from expert/consultants
• Concept check – Is it firm concept? Site, load, system size and configuration – Is schedule fixed? – Is budget made based on expected generation output and its cost? 14
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Off Grid: PV hybrid systems within minimini-grid: Check list on design (5) • Reconfirmation of design condition – Firm policy? – For what? Where? How big? How is the system? When? How much? – Constraints – Ambient environment, Site condition, existing electrical equipment, regulation, necessary procedure • Design – Direction and angle of PV panel – maximize output under the given condition – Array configuration and its installation – Foundation, mounting frame, waterproof, intensity calculation – Material, antirust and anti-corrosion of mounting frame material – Compliance with regulation – In accordance with the project purpose – Established schedule, expected result and project cost. • Application – Subsidy – Application for local authority • Design check – Fixed detail design, budget, construction schedule? – Finish all the necessary application? – Completed adequate bidding? 15
Off Grid: PV hybrid systems within minimini-grid: Planning & design (1) • Output fluctuation of REN – Effect on voltage and frequency – Traditional generator absorbs fluctuation of load, but REN generates fluctuation. – Without output adjustable power source, it’s very difficult to keep voltage and frequency. • Measures – Measures at each REN – Hybrid with other power source – Use of battery system – Use of dummy load
16
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Off Grid: PV hybrid systems within minimini-grid: Planning & design (2) • How to have power source for base load – Requirement Reliability Power controllability Low generation cost • Can REN be a base power source? – Micro-hydro: Possible, if stable flow exists. – Wind: Low reliability. But wind firm may be. – PV: No, because of daytime only – Biomass: Possible, if stable fuel supply exists.
17
Off Grid: PV hybrid systems within minimini-grid: Planning & design (3) • Combination of various REN
Reliability
Power controllability
Generation cost
Constrain on site
Difficulty on maintenance
Total evaluation
Micro-hydro (river-in-flow)
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Micro-hydro (storage pond) Wind
PV
Biomass
:Excellent
:Good
:Fair
:Poor 18
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Off Grid: PV hybrid systems within minimini-grid: Planning & design (4) •
Hybrid of REN (without genset) a.
Improve reliability
b.
Improve power controllability and realize output smoothing
c.
Complementary combination: Enlarge storage reservoir Not one big REN, but many small REN
Common-use of electrical equipment
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Power source for base load
PV
Biomass
Micro-hydro (storage pond)
Micro-hydro (river-in-flow)
b
a, b
a
a, b, c,
a, b, c,
c
Micro-hydro (river-in-flow)
a, c
a, c
Micro-hydro (storage pond)
a, c
Wind
Biomass
:Excellent
Wind
PV
b
:Good
:Fair
:Poor 19
Off Grid: PV hybrid systems within minimini-grid: Planning & design of micromicro-hydro • Concept design of micro-hydro – Layout of major engineering structure – Identify head – Investigate information of water flow – Design of max water consumption • Basic design of major engineering structure – Civil – Electrical
20
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Off Grid: PV hybrid systems within minimini-grid: Planning & design of wind power • Concept design – Site selection – Investigate information of wind condition – Investigate surrounding natural and social condition • Basic design – Detail survey of wind condition – Wind measurement (point, method) – Analysis of measured data – Simulation – Evaluation Finalize point and capacity – Environmental assessment – Land and soil survey
21
Off Grid: PV hybrid systems within minimini-grid: Planning & design of biomass energy • Concept design – Identify biomass resource Cost Supply stability – How to collect biomass? In-house, collection, delivered – Investigation of plant size Amount of biomass resource, area, demand – How to use energy (power, heat) – Reuse/disposal of by-product (dust, sludge, effluent…)
22
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Off Grid: PV hybrid systems within minimini-grid: Operation & maintenance • • • •
Load forecasting is most important. Aim to full utilize PV power. Reserve battery energy for emergency case. Adjust charge/discharge energy in accordance with varying load.
Daytime: Battery charge by REN source Nighttime: Battery discharge for load Investigate charge/discharge time Calculate required battery capacity
Source: NEDO
23
Normal grid (Examples of grid connected system)
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Grid Connected Solar PV Workshop Palau November 1-5,2010
Grid connected system No
Title
(1)
SHS
(2)
(3)
Mini grid
Grid connected Large PV system & Hybrid system
Sub-t.itle
Main Grid connection
Supplied power
Gen Size (approx.)
Genset
Other RNE
Battery system
Note
DC SHS
Off
DC
< 1kW
No
No
Yes
AC SHS
Off
AC
< 1kW
No
No
Yes
PV Mini grid
Off
AC
1 - 50kW
No
No
Yes
50 to 600 Households Battery charge station
PV hybrid systems within mini-grid
Off
AC
10 - 500kW
Optional (a few hours per day)
Wind biomass micro-hydro etc.
Optional
New components
Grid connected large PV system
On
AC
> 40kW
No
No
Optional
With reliable grid (24H supply)
Grid connected hybrid system
On
AC
> 100kW
Basically No. Optional (a few hours per day)
Wind biomass micro-hydro etc.
Optional
With reliable grid (24H supply)
2
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Grid connected: Large PV system: System configuration PV panel
Inverter
PCS
Grid-connected Optional battery For a for village (> 40kW)
Optional Battery
Grid
Delivers the power to the households and common equipments through a grid
24 hours power supply by existing generators
3
Grid connected: Large PV system: Type of grid connection Grid connection - Low voltage - High voltage
No islanding operation
Reverse flow No reverse flow
Buy power from grid if load > PV output Sell power to grid if load < PV output Anytime load > PV output
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Reverse power flow relay
Islanding operation
Reverse flow
On reverse flow, same as above
No reverse flow
With battery system, backup power shall be supplied even in power outage
Source: NEDO
4
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Grid connected: Large PV system: Examples (1)
Source: KEPCO
Installed in 2008 at Funafuti, Tuvalu by E8 (KEPCO) Connected with grid 40kW PV Decrease approx. 50t-Co2/y [100 klbs-Co2/y]
5
Grid connected: Large PV system: Examples (2)
Present (As of 2010 Oct)
Final
Area
60000 m2 = 72000 yard2
200000 m2 =240000 yard2
Generator capacity
2850 kW
10000 MW
Generation output
3000MWh / year
11000MWh / year
CO2 reduction/year 1,000,000kg = 2,2000,000pound
4,000,000kg = 8,8000,000pound
Operation start
2011.10 ~
2010.10.5 ~
6
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Grid connected: Large PV system: Examples (3)
Source: NEDO
Installed in 2005 at Beijing, China by NEDO (TEPCO+PVTEC) Office use plus connected with 10kV grid 140kW PV Comparison of various kind of PV modules (crystalline, amorphous) 7
Grid connected: Large PV system: Examples (3)
Source: NEDO
8
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Grid connected: Large PV system: Examples (4)
Source: NEDO
Installed in 2004-2007 at Ohta, Japan by NEDO (Kandenko et al.) 553 residential houses Total 140kW PV, connected at 100V with 6.6kV distribution line Evaluation of the islanding operation protection 9
Grid connected: Large PV system: Examples (4)
PV
Junction box
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Inverter etc. Load
Source: NEDO
Installed in 2004-2007 at Ohta, Japan by NEDO (Kandenko et al.) 553 residential houses Total 140kW PV, connected at 100V with 6.6kV distribution line Evaluation of the islanding operation protection 10
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Grid connected: Large PV system: System configuration PV panel
Inverter
PCS
Grid-connected Optional battery For a for village (> 40kW)
Optional Battery
Grid
Delivers the power to the households and common equipments through a grid
24 hours power supply by existing generators
11
Grid connected: Large PV system: Type of grid connection Grid connection - Low voltage - High voltage
No islanding operation
Reverse flow No reverse flow
Buy power from grid if load > PV output Sell power to grid if load < PV output Anytime load > PV output
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Reverse power flow relay
Islanding operation
Reverse flow
On reverse flow, same as above
No reverse flow
With battery system, backup power shall be supplied even in power outage
Source: NEDO
12
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Grid connected: Large PV system: Examples (1)
Source: KEPCO
Installed in 2008 at Funafuti, Tuvalu by E8 (KEPCO) Connected with grid 40kW PV Decrease approx. 50t-Co2/y [100 klbs-Co2/y]
13
Grid connected: Large PV system: Examples (2)
Source: NEDO
Installed in 2005 at Beijing, China by NEDO (TEPCO+PVTEC) Office use plus connected with 10kV grid 140kW PV Comparison of various kind of PV modules (crystalline, amorphous) 14
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Grid connected: Large PV system: Examples (2)
Source: NEDO
15
Grid connected: Large PV system: Examples (3)
Source: NEDO
Installed in 2004-2007 at Ohta, Japan by NEDO (Kandenko et al.) 553 residential houses Total 140kW PV, connected at 100V with 6.6kV distribution line Evaluation of the islanding operation protection 16
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Grid connected: Large PV system: Examples (3)
PV
Junction box
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Inverter etc. Load
Source: NEDO
Installed in 2004-2007 at Ohta, Japan by NEDO (Kandenko et al.) 553 residential houses Total 140kW PV, connected at 100V with 6.6kV distribution line Evaluation of the islanding operation protection 17
Other various applications of PV ( On the factory roof )
Capacity:820kW
Capacity:50kW
Capacity:260kW 18
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Other various applications of PV ( On the wall surface )
Capacity:66kW Capacity:4kW
Capacity:15kW 19
Technical requirements for grid interconnection
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Grid Connected Solar PV Workshop Palau November 1-5,2010
The merit of grid interconnection from the generator installer 〇Easier to maintain power quality 〇Boost the operating rates of generator 〇Absorb fluctuation of generator output (ex. PV, wind power) 〇Improve reliability and flexibility in case of generator’s fault or maintenance check 〇Chance to sell electric power to the power company 2
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
The Merit of Grid interconnection (1) Easier to maintain power quality
Hard to keep system voltage
Grid
×
Distributed generation
Disconnected from grid ↓ Hard to keep system frequency
Distribution substation
G
Feeder
3
The Merit of Grid interconnection (2) Boost the operation rates of generator
Pmax
G
L L
High performance generator
G High performance generator
＝
G
Restricted operating rates
Grid
Pmax
G lower generation cost as a total 4
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
The Merit of Grid interconnection (3) Improve reliability and flexibility in case of generator’s fault or maintenance check Generator’s fault or periodical inspection
G
L
G
L Blackout or Standby generator is needed
Grid
G L
Grid
G L
5
Considerable points in case of grid interconnection ～ Power Grid
Load Load
Load Load
Power from the grid and the generator are mixed, in case of interconnection
Generator
Ｇ
〇Secure supply reliability and maintain power quality (Voltage, frequency, harmonics, etc) ○Secure Public safety and prevent equipment damage 6
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Considerable points in case of grid interconnection (detail) Secure supply reliability
・Dispersed generator’s fault should not effect the reliability of power grid ・Prevent expansion of fault (by exceeding short circuit capacity, by malfunction of distribution over current protection relay, etc) ・Relay protection coordination is important
Maintain power quality ・Possibility of harmful effect to other customers via grid ・Reduce voltage fluctuation of distribution line by interconnecting of dispersed generator ・Reduce harmonics level from dispersed generator etc Secure public safety and prevent equipment damage
・Prevent islanding to be secure public safety, especially for distribution line which is easily accessible to public
Basic principle is disconnecting generator from the power grid in case of problem
The necessity of grid interconnection code ＜Request from generator installer side＞ ＞
・simplification of facility (low cost) ・request higher operation rate of generator ・request to shorten the period of construction
Generally, to seek cheaper facility and simpler operation, the quality of facility shows a tendency to be lower.
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Conflict of request
＜Request from power system operator＞ ＞
・countermeasure by facility to secure safety （→higher cost） ） （→ ・higher priority on power quality and public safety （→decrease the operation rate of generator by output control) （→ ・sufficient preliminary check （→prolong the period of construction by preliminary check) （→ Generally, to seek higher security and power quality, request shows a tendency to be higher. 8
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
The necessity of grid interconnection code (continue) Interconnection to power grid of many, various type of generator
＜Request from generator installer side＞ ＞
Effect to operation, administration, maintenance of Power system,etc
＜Request from power system operator＞ ＞
To To harmonize harmonize request requestfrom from both both side, side, to to secure equality and transparency of generator secure equality and transparency of generator interconnecting interconnecting process, process,grid gridinterconnection interconnection code is necessary. code is necessary. 9
Category of grid interconnection by voltage level Category
Power Capacity per customer (P)
Low voltage distribution line (100V, 200V)
P < 50kW (in principle)
High voltage distribution line (6600V)
P < 2000kW (in principle)
Extra high voltage line
2000kW Pl case is possible ・RPR can not be applied ・voltage rising by reverse power flow
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Fault protection of feeder with distributed generation
High voltage feeder
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Generator
Distribution substation
Without disconnection of distributed generation, ground fault continues even by breaking CB at substation. (Threat of equipment damage and electric shock)
It is necessary for distributed generation to be disconnected in concert with the fault detection of system.
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
37
Preventing of islanding
①
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Substation
② CB break
③
① Crane touches feeder. ② Fault detection, then CB break.
※PV system is running (islanding operation) ③ Threat of electrical shock for worker near crane and public. 38
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Protective Relay (Example of PV system) Countermeasures against PV system breakdowns Symbol
OVR
UVR
Name
Over Voltage Relay
If an abnormal increase occurs in voltage generated by the PV system, the over voltage relay detects the abnormal voltage, then separates the PV system from the grid after a predetermined period of time.
If an abnormal decrease occurs in voltage generated by the PV system, the under Under Voltage voltage relay detects the abnormal voltage, Relay then separates the PV system from the grid after a predetermined period of time.
Countermeasures against transmission line faults (short-circuit) As a countermeasure against short-circuit in transmission line, UVR can be shared among transmission line. 39
Protective Relay (Example of PV system)
Countermeasures against transmission line fault
Symbol
OVGR
Name
Ground Fault Over Voltage Relay
In the case of a transmission line fault, the PV system might leak such a low current that OCGR cannot operate. In contrast, OVGR can detect ground fault voltage and cut the PV system off from the grid.
* If requirements are satisfied, OVGR can be omitted.
40
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Protective Relay (Example of PV system) Precautions against PV system Islanding Operation (with reverse power flow) Symbol
Name
Function
OFR
Over-Frequency Relay
Abnormal over-frequency (detect islanding)
UFR
Under-Frequency Relay
Abnormal under-frequency (detect islanding)
In addition to OVR, UVR, OFR and UFR, active detection of the PV system islanding operation, including abnormal detection, is essential for equipment.
41
Protective Relay (Example of PV system) Precautions against PV system Islanding Operation (with no reverse power flow) Symbol
Name
RPR
Reverse Power Relay
UFR
Under-Frequency Relay
Function Prevention of reverse power flow (detect islanding) Abnormal under-frequency (detect islanding)
An accident might occur on upper side transmission line. In the case of an interconnected distribution line fault, after the circuit breaker for the distribution line opens the circuit, the fault point may disappear. For electrical work, worker may open a switch for a transmission line. In such special cases and outage, some types of relays fail to detect system faults, thus increasing the risk of the PV system islanding operation. Unless a reverse power flow occurs in the interconnected system, RPR and UFR should be installed in the system. 42
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Protective Relay (Example of PV system) Type of islanding detection method
Active detection
Add disturbance signal from generator to grid continuously On power outage, detect increased response to disturbance signal Secure detection, but need several seconds
Passive detection
On power outage, detect phase change of P, Q balance Possible instant detection But used as backup of active detection for grid connected generator in high voltage, because of little change at rotating generator
→ Use multiple detection to detect absolutely 43
Protective Relay with built-in power conditioner Example of protective relay for grid interconnected system (with built-in Power Conditioner) UVR (under voltage relay): System short circuit and blackout OVR (overvoltage relay) : Abnormal overvoltage OFR (over-frequency relay) : Abnormal over-frequency UFR (under-frequency relay): Accident on higher-voltage transmission line Example of protective relay for grid interconnection system (of external installation type) OVGR (overvoltage ground relay): Ground fault RPR (reverse power relay): Prevention of reverse power flow
44
(1) Interactive in Low-voltage
(Single-phase power conditioner)
(2) Interactive in High-voltage (Three-phase power conditioner + OVGR)
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Example of system block diagram
45
Example of system block diagram (3) Deemed low-voltage Grid-connected type, no reverse power flow (Single-phase and three-phase power conditioners)
46
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
TR for interconnection 7. Neutral point grounding system 8. Automatic load shedding device 7. Neutral point grounding system When necessary for grounding at a neutral point of generation facilities or interconnection facilities on a high voltage side, those who interconnect generation facilities with high voltage distribution systems consult with power company and adopt a grounding system designated by power company. 8. Automatic load shedding device When there is a possibility of overloading the interconnected distribution lines at the time of a loss of generation and so forth, those who interconnect the generation facilities with power systems need to take measures that automatically limit the load.
47
TR for interconnection 9. Device to confirm no-voltage on distribution line 9. Device to confirm no-voltage on distribution line A device designed to confirm no voltage on distribution lines is installed at the outlet of distribution lines from a substation for distribution in order to prevent faults at the time of automatic reclosing. However, such a device can be omitted if either of the following items is satisfied: (1) The installer of the generation facility does not require automatic reclosing because of connection to a line for exclusive use
48
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
TR for interconnection 9. Device to confirm no-voltage on distribution line (2) Either of the following conditions is satisfied when there is a reverse power flow: a. An transfer tripping protection and a device with islanding detection function (only active type) are installed and each of them disconnects power systems using different circuit breakers. b. Devices with two or more islanding detection functions (including one or more active type) are installed and each of them disconnects power systems using different circuit breakers. c. A device with islanding detection function (only active type) and a reverse power relay whose setting value is less than the minimum load of distribution lines while the generators are in operation and each of them disconnects power systems using different circuit breakers, are installed.
49
TR for interconnection 9. Device to confirm no-voltage on distribution line (3) Either of the following conditions is satisfied when there is no reverse power flow: a.The conditions of Item (2) above b.A protective relay, current transformer, voltage transformer, circuit breaker, and a wiring of power source for control concerning system interconnection are connected in dual series and yet sequentially, allowing them to back each other up. However, one of the above-mentioned dual systems can be replaced by one or more of the following methods: - The protective relays of one of the above-mentioned dual systems can be made of the under power relays only; - One current transformer can be combinedly used in the 1st and 2nd series when an under-power relay is installed at the end of a current transformer; and - One voltage transformer can be combinedly used in the 1st and 2nd series when an under-voltage relay is installed at the end of a voltage transformer. 50
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
TR for interconnection 10. Telephone facility for security communication 10. Telephone facility for security communication When a circuit breaker for system interconnection kicks in because of an on-site problem, power systems, and so forth, those who operate generation facilities and power company communicate with each other promptly and accurately. Telephone facilities for security communication (such as private telephone facilities for security communication or a telephone of a leased line for exclusive use of a telecommunications company) need to be installed between them. However, telephone facilities for security communication may use any subscribed phones or cellular phones if all the following conditions are satisfied:
51
TR for interconnection 10. Telephone facility for security communication - A system that allows direct communication with engineers not passing through the exchange of one who operates generation facilities is introduced (not a switchboard number system via the exchange, but a single number system directly connected to the technical office) and it is permanently installed at the place of maintenance /supervision of generation facilities; - A system capable of interrupting even while the number is engaged (for example, the so-called catch-phone system) is introduced; - A system that allows communication even in case of outage; and - It is clearly specified in a safety regulation that if communication with the power company concerned cannot be made in the event of disasters or other problems, generation facilities are disconnected or cease to operate until the communication is recovered. 52
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
TR for interconnection 11. Prevention of reverse power flow through main transformer 11. Prevention of reverse power flow through main transformer As a power flow from a high voltage side to a special high voltage side through a main transformer for distribution (hereinafter referred to as “a reverse power flow through a main transformer”) may cause some problems in voltage management and protection coordination of distribution systems, it is important to prevent such a power flow through a main transformer. To make sure that a generation facility with a reverse power flow will not always cause such a reverse power flow through a main transformer, the occurrence of the flow is judged based on generation output and load patterns when interconnections are examined. If it is deemed that a reverse power flow through a main transformer is likely to occur, measures to control generators and similar actions will be taken.
53
Day 4
1
Guidline of construction and mantenance
e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
Grid Connected Solar PV Workshop Palau November 1-5,2010
Index
1 ２ ３ ４ ５ ６ ７
－ System Construction Design － Design and Construction Flow － Construction Management Points － Pricing Guidelines － Field Inspection Items － Maintenance － Economical Effects
2
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1 e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1 e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
1.System Construction Design
System
Laws and regulations
Guidelines
Electrical work
Architectural work Architectural Code
Wiring rules
GridConnection
-Voltage -Protection Coordination
Piping and wiring routes
Waterproof construction
- Voltage drops - Scaffolding - Use of existing routes
- Lead-in cables - Equipment sheds
Piping and wiring sizes
Earthing
Maintenance
- Existing earthing - Safety type regulations
Foundati on work
Support Structure construction
- Wind pressure calculation - Waterproof roofs and rooftops
- Wind pressure calculation - Electromagnetic interference
Compliance
: Design based on laws and regulations
Easy construction
: Design that facilitates safe construction, and shortens construction term
Low cost construction
: Design that reduces material and labor expenses 3
2. 1 Design and Construction Flow Site investigation
Design
- Installation Areas On ground or roof Length, width and azimuth -Roof type Deck roofs or sloping roofs Roofing materials, Waterproof types - Obstacles Poles, buildings, antennas, mountains, trees (and other obstacles that cast shadows on PV Arrays.) - Piping Routes Existing piping routes and wiring diagrams - Equipments Installation locations Switchboards, control boards, Power Conditioners, instrumentation and display - Routes for Carrying in Crane or Wrecker installation location and temporary placement space - Diagram Skeleton diagram from electric power company lead-in cable to interconnection point - Contract with electric power company Price of buying and selling power
Construction
Trial operation and Adjustment
- Foundation work (rooftop)
- Visual Inspection
- Carrying in
- PV module Support Structure Earthing
- PV modules Installation
- Electrical piping and wiring
- Devices Installation
- Electric connection work
Completion
Cracks, damage of devices - Insulation Resistance test Cable insulation resistance - Open-Circuit voltage test Voltage measurement of each series of PV modules - Setting of Power Conditioner protective relays Setting based on discussion with the electric power company - Adjustment of measuring instruments Deviation from Power Conditioner indicating values - Adjustment of indication Discrepancy between measurements and indications 4
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
2. 2 Site investigation Guideline (1) Area of PV array installation site
Investigation the area of installation site
Environment
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
Environmental Survey
East-west width and north-south length are measured.
Verification the influence of shadows cast by buildings, tall trees and other obstacles. Verification possible damage due to weather like salt damage, snow, wind or other weather conditions.
Azimuth Azimuth and Angle
Verification possible damage due to weather like salt damage, snow, wind or other weather conditions. 5
2. 2 Site investigation Guideline (2) Equipments Installation Site
Installation Site Survey
Condition of Electric Power Transmission e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
Verification the influence of shadows cast by buildings, tall trees and other obstacles.
Discussion with the electric power company
Recognition of Regulations and Standards
Local Ordinances
Junction boxes, centralized control boards, interconnection switchboards, transformers
Verification the type of power source system and determination the type of interconnection. Staff verifies voltage fluctuations and frequency variations.
Approval to the System for Interconnection 6
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1 e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1 e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
2. 3 Design Guideline (1) PV module Selection
Determination of Azimuth and Angle
PV Module Selection
Output Maximization
Number of PV modules and PV array Capacity Determination
Dependence on Area of Installation site
Power Conditioner Selection
According to PV array Capacity
Manufacturer, type, capacity
Optimum Orientation (generally same with Latitude) and Azimuth are determined.
Required Capacity
Manufacturer, type, capacity
7
2. 3 Design Guideline (2) PV array Layout Determination PV array Layout Determination
Series and Parallel connection should be determined according to rating input voltage of Power Conditioner. PV module characteristics
PV module Support Structure Design
Foundation Design
Ground-mounted type Deck roofmounted type Sloping roofmounted type Wall-mounted type Weight, Wind Pressure
Design based on strength calculation of PV array angle Design based on mounting method and structural strength
Design based on strength calculation 8
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1 e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
2. 3 Design Guideline (3) Equipments selection
Interconnection circuit breaker selection
Indoor type or Outdoor type should be selected. Power conditioner protection
Provision of watercourses for carrying away rainwater Selection based on power conditioner capacity
Selection of protective relays
Protection from accidents of grid
Selection based on electric power conditions, rules and standards
Selection of piping and wiring between devices
Minimization of wiring paths
Selection based on allowable current, voltage drops, standards and rules
9
2. 4 Example systems
PV modules
Selling electricity
Power conditioner
Electric power company
e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
Buying electricity
Storage batteries
Charge and discharge controller
Offices and/or factories
Display system
Applicable to disaster prevention (system includes storage batteries.) * Capacity of storage batteries is determined according to setting of load amperage, load types and operation time.
10
GridConnected System
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1 e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
Storage Applicable to emergency batteries are operation. used. Storage batteries are not Used in houses and/or buildings. used.
Reverse Flow to Grid
Storage batteries are used. Storage batteries are not used.
No Reverse Flow to Grid
e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
2. 5 System type (1)
Applicable to emergency operation. Large power consumers use this type. Large power consumers use this type.
11
2. 5 System type (2) Stand-Alone system
Limited Loads
DC
AC
General Loads
DC
AC
Storage batteries are used. Storage batteries are not used. Storage batteries are used. Storage batteries are not used. Storage batteries are used. Storage batteries are not used. Storage batteries are used. Storage batteries are not used.
Street lights, radio equipment power sources, traffic lights DC pumps, battery chargers, fans,
Lighting systems
AC pumps
Electrification in low-population villages No examples
Electrification in higher-population villages No examples 12
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1 e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
2. 6 Power conditioner selection (1) Power Conditioners are classified into three: (1) Low-voltage interconnected system (single-phase power conditioner) Interconnected with low-voltage distribution lines that supply power to general houses. Incoming voltage : Single-phase three-wire system of 100/200 V Interconnected point : Single-phase three-wire system of 100/200 V (2) High-voltage interconnected type (three-phase power conditioner + OVGR) Interconnected with high-voltage distribution lines that supply power to factories and other high demanders. Incoming voltage : Three-phase three-wire system of 6600 V Interconnected point : Three-phase three-wire system of 200 V (3) Deemed low-voltage interconnected types (single-phase and three-phase power conditioners) Despite the high incoming voltage, PV system output is much less than the contract demand. Incoming voltage : Three-phase three-wire system of 6600 V Interconnected point : Three-phase three-wire system of 200 V : Single-phase three-wire system of 100/200 V 13
2. 6 Power conditioner selection (2) Power Conditioner installation space Ambient temperature : -5 ºC to + 40 ºC (normal operation, standby) Relative humidity : 30% to 90% Installation site : Indoor Outdoor (enabled by accommodating in a cubicle.) To provide spaces for inspection and heat dissipation, it is necessary to place the inverter off the walls and the top as shown below. It is possible to change side walls to parallel boards.
e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
Distance to top: 500 mm or more
Distance to front: 1,000 mm or more
Distance to back: 100 mm or more
[Side View] Dimensions differ depending on the power conditioner manufacturer. Specifications of indoor inverters of 10 kW to 30 kW (900 W x 1875 H x 700 D) Weight: 230 kg (10 kW) 290 kg (20 kW) 370 kg (30 kW) * The above example is a power conditioner of the standard system (of interconnection type). It is recommended that the power conditioner should be placed outdoors or in an electric-generation room because of the harmonic noise level. 14
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1 e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
2. 7 Equipment type
3. Construction Management Points (1) Site investigation
Installation site confirmation
Verification of installation conditions Confirmation of interconnect ed point
Roof-mounted
Confirm that a lift to the roof is provided.
Wall-mounted
Determine whether or not the provision of scaffolding and a man lift truck is necessary.
Ground-mounted
Recognize the work space for construction equipment (s).
Deck roof
Check waterproof type.
Folded plate roof
Check folded plate fixture type.
Sloping roof
Verify inclination and anti-slip properties
Circuit breaker for interconnected system
Confirm an extended space.
High-voltage protection relay
Verification of piping and wiring routes
Route check
Carrying in route check
Carrying in route check
If circuit break is needed for relay installation, confirm the circuit break point. Determine whether or not the provision of scaffolding and worker lift truck is necessary. Determine whether the existing route can be used. Verify working location of construction equipment (wrecker). 16
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
3. Construction Management Points (2) Getting there
Marking
e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
Carrying in
Temporary office
Provide an on-site office.
Determine whether or not the provision of scaffolding and worker lift truck is necessary.
Temporary yard
Provide a materials yard.
Provide a yard close to the site.
Marking
Marking based on reference line
Check the drawing. Confirm shadows.
Crane placement
Placement of crane at predetermined location
Rooftop care
Prevention with panel Provision of access made by planks. Craning the PV module support structure and PV modules
Verify hoisting loads and construction equipment. Confirm the operating, hanging and signaling workers. Prohibit admittance to work area. Inspect the hoisting accessory. Install to prevent the wind from blowing PV cell modules. Bind planks.
Craning
Confirm the stability of the crane and load at a lift of 30 cm above the ground. Do not enter beneath loads. 17
3. Construction Management Points (3) PV module Support Structure Installation
Fixture mounting
Mount fixture.
Mount fixtures to marking.
Support Structure Assembling
Assemble the Support Structure
With stainless bolts, mount the Support Structure to fixture. Confirm that the horizontal and vertical those should be.
PV modules Installation
PV module Installation
Mounting PV modules to the Support Structure
Carefully handle the PV module, and mount it to the fixture without damage. Align modules flush with longitudinal and lateral lines. During mounting, workers shall communicate with one another. 18
Electrical Piping and Wiring work
e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
3. Construction Management Points (4) Wiring between each PV modules Connection between each PV modules
Wiring of connector cables between each modules Wiring of connectors between each modules
Equipment installation
Installation Power Conditioner and Interconnection board
Laying electrical conduits
Laying electrical conduits Laying cable rack
Laying cable
Laying cable
Getting cables straight Connecting wires
Connection to switchboards
Confirm that the circuit and system are constructed according to the drawings. Confirm the polarity and system of the cable connectors, and connect them. Confirm that the cable plug is securely connected. After the connection between modules, cover terminals with insulation tape to prevent short-circuits. Install according to the drawing. Install so that devices cannot cast shadows on each other. Be careful not to damage the casing. Using hangers, saddles and other metal supports, mount conduits. Mount according to the drawing. With metal supports, mount the cable rack. Mount according to the drawing. Select line types and distance, according to design drawing. Be careful not to damage the covering of the cable. Fix cables to rack. Use of appropriate terminal lugs
19
3. Construction Management Points (5) Outage work (altering switchboards)
Breaker, OVGR and extension Circuit breaker and OVGR extension
Circuit breaker extension
Inspection
Outage
With electroscope, confirm an outage. Earth units. Earth all devices.
ZPD and OVGR are mounted.
ZPD and OVGR are mounted in place.
Outage
With an electroscope, confirm outage.
Mount breaker.
Mount circuit breaker in place.
Restoration
Check inside of cubicle.
Visual Inspection Open-Voltage Measurement
Visual Inspection of Equipments
Confirm that devices are free from cracks.
Measurement of voltage per system with tester
Measure the voltage of each circuit in inverter, and record.
Insulation resistance measurement
Measurement of insulation resistance with tester
Check batteries. Verify the connections to the earthing terminals.
PV array circuit
Measure voltage across earthing terminals, and record. Measure voltage across batteries and across lines, and record it.
Voltage across Power conditioner and Interconnection board Voltage across Interconnection board and interconnected point
Measure voltage between earth and batteries and across lines, and record it.
20
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1 e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
3. Construction Management Points (6) Trial operation and adjustment
Power Conditioner setting and operating test
Adjustment and confirmation of measuring instruments Adjustment of indication on display, and confirmation.
Power Conditioner setting
Adjustment of measuring instruments Confirmation of measuring instruments Adjustment of display. Confirmation of display.
Operate in accordance with the inverter operating procedure. Adjust according to measuring guidelines. The measurements are compared with the indication of the inverter. Adjust the display to an easy-to-see angle. Compare the display of the measuring instrument with the power conditioner indication.
Interconnection
Delivery 21
4. Pricing Guidelines（１） Guidelines（１） Equipments Cost
PV module Power conditioner Switchboards (Junction boxes, Concentrated Boards and Interconnection Boards), Transformers PV module Support Structure General electrical materials
e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
Confirm the setting by the electric power company.
Construction Cost
On-site management expenses
PV module Support Structure Installation PV modules mounting PV modules wiring and connections Equipments mounting General electrical work Management expenses
Manufacturer, type, capacity Manufacturer, type, capacity Selected by Power Conditioner specification Installation type Compliance with the technological standards Consider the past records Consider the past records Consider the past records Consider the past records Consider the past records SV, offices, worker expenses
22
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1 e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
4. Pricing Guidelines（ Guidelines（2） Transport expenses, outsourcing expenses, including various securities
Transport expenses Carrier
Travel and transportation expenses
Installation site
Construction equipment expenses
Construction equipment
On-site overhead expenses
Overseas travel expense
Wrecker, forklift, outsourcing expenses
10% of equipment expenses
23
5. Self Inspection Items 5.1 Visual inspection and verification test of structure and quantity （1）PV Modules
（2）Support Structure for PV modules （3）Power Conditioner (s) （4）Display System
（5）Junction Box (s), Interconnection Switchboard, MCB
e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
5.2 Equipment installation and wiring/connection inspection （1）Equipment installation inspection
（2）Wiring/Connection verification test
5.3 Insulation resistance test （1）Wiring between each PV Modules （2）Wiring between various equipments 5.4 Open-circuit voltage test/ground resistance test （1）Open-circuit voltage of PV module
（2) Ground resistance if systems are grid-connected 24
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
5.1 Visual inspection and verification test of structure and quantity (1) （1） PV module visual inspection and power output test Item
e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
Appearance
Output
Inspection details
Means of inspection
・Check if there is any damage, cracking or deformation in the PV module appearance.
Visual inspection
・Confirm that PV modules are appropriately arranged.
Consistent with Spec. of drawings
Result
・Check against manufacturer’s inspection records when omitting the field output tests.
25
5.1 Visual inspection and verification test of structure and quantity (2) （2）Visual inspection of Support structure for PV array Item
Appearance
Installation
Wiring
Inspection details
Means of inspection
There is no deformation or strain.
Visual inspection
There is no peeling of galvanized steel welded to support structure.
Visual inspection
The support structure is appropriately arranged.
Consistent with Spec. of drawings
There is no loosening in screws, bolts and fixtures.
Visual inspection
Bolt tightening is appropriately conducted.
Visual inspection
There is no loosening in the connections between photovoltaic modules.
No loosening is confirmed by touching and visually.
Exposed cables behind the photovoltaic module are wired in order.
Visual inspection
Cables are supported by fixing devices.
Visual inspection
Earth conductors are connected to the PV module Support Structure.
Visual inspection
Result
26
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1 e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1 e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
5.1 Visual inspection and verification test of structure and quantity (3) （3）-1 Power Conditioner Visual inspection Item
Means of inspection
Inspection details
Result
Appearance
There is neither peeling of surface coating nor deformation.
Visual inspection
Installation
There is no loosening in screws, bolts and fixtures.
Visual inspection
P/N（ （+/-） ） are correctly connected at the Power Conditioner input.
Visual inspection, Multi meter
R/S/T are correctly connected at the threephase output.
Visual inspection, Multi meter
Low voltage cable +/- are correctly connected at its input/output.
Visual inspection, Multi meter
Earthing conductors are connected.
Visual inspection
Cables are connected in order.
Visual inspection
The panel internal is clean.
Visual inspection
Wiring
27
5.1 Visual inspection and verification test of structure and quantity (4) （3）-2 Power Conditioner Performance test Item
Inspection details
Model/type
Matching Check to the Specification document
Protective relay test (at factory)
Check factory inspection records on behalf of the relay test in field.
Detection of Islanding operation
MCCB（ （ELCB） ） is turned off and operation is shutdown in an instance.
20 seconds standby after power restoration
The power conditioner automatically starts 20 seconds after power restoration.
Performan ce test
Performance
Result
Remarks
Acceptable
Check to factory inspection records.
Acceptable
20[s]
after restarted
Acceptable
The time to restoration shall be consistent with Tech. Spec.
Regarding output inspection/test of relays, check manufacturers’ factory inspection records on behalf of conducting field inspection/test. 28
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1 e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1 e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
5.1 Visual inspection and verification test of structure and quantity (5) （4）Display System Visual Inspection Item
Inspection details
Means of inspection
Appearance
There is neither peeling of surface coating nor deformation.
Visual inspection
Installation
There is no loosening in screws, bolts and fixtures.
Visual inspection
Nameplate
There is no defect to or peeling of nameplate.
Visual inspection
AC200V control power cables are correctly wired.
Visual inspection, Multi Meter
Low voltage cables are correctly wired and there is conduction.
Visual inspection, Multi Meter
Cables are wired in order.
Visual inspection
The panel internal is clean.
Visual inspection
Wiring
Result
LED verification test Item
Inspection details
Means of inspection
Verification of quantity
The generated electricity is consistent with the total of the numerical values shown in the power conditioner LCD.
Visual inspection
Result
＊Input signals from the secondary cable in the transformer inside the interconnection switchboard to verify the indicated values on the LED screen. ＊Visually check the numerical values indicated by power conditioner panel LCD or data collection system monitor to verify there is no error in the generated electricity of photovoltaic module and Power Conditioner output. 29
5.1 Visual inspection and verification test of structure and quantity (6) （5）-1
Junction Box, Interconnection Switchboard and MCB
Visual Inspection of junction box-1 Item
Inspection details
Means of inspection
Appearance
There is neither peeling of surface coating nor deformation.
Installation
There is no loosening in screws, bolts and fixtures.
Visual inspection
P/N（ （+/-） ） are correctly connected at the junction box input.
Visual inspection, Multi Meter
P/N（ （+/-） ） are correctly connected at the MCCB output.
Visual inspection, Multi Meter
Earth conductors are connected.
Visual inspection
Cables are wired in order.
Visual inspection
The panel internal is clean.
Visual inspection
Wiring
Result
Visual inspection
30
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1 e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1 e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
5.1 Visual inspection and verification test of structure and quantity (7) （5）-2 Junction Box, Interconnection Switchboard and MCB Visual inspection of interconnection switchboard Item
Inspection details
Means of inspection
Appearance
There is neither peeling of surface coating nor deformation.
Installation
There is no loosening in screws, bolts and fixtures.
Visual inspection
U/V/W are correctly connected at the inverter input.
Visual inspection, Multi Meter
U/V/W are correctly connected at the main MCCB output.
Visual inspection, Multi Meter
Earthing conductors are connected.
Visual inspection
Cables are wired in order.
Visual inspection
Wiring
Result
Visual inspection
The panel internal is clean.
Visual inspection
U/V/W phase indicator shows the positive phase at the Power Conditioner input
Visual inspection, phase indicator
31
5.1 Visual inspection and verification test of structure and quantity (8) (5)-3 Junction box, interconnection switchboard and MCB Visual inspection of MCB Item
Inspection details
Means of inspection
Appearance
There is neither peeling of surface coating nor deformation.
Installation
There is no loosening in screws, bolts and fixtures.
Visual inspection
U/V/W are correctly connected at the main MCCB input.
Visual inspection, Multi Meter
U/V/W are correctly connected at the main MCCB output.
Visual inspection, Multi Meter
Earth conductors are connected.
Visual inspection
Cables are wired in order.
Visual inspection
wiring
Result
Visual inspection
The panel internal is clean.
Visual inspection
U/V/W phase indicator shows the positive phase at main MCCB output.
Visual inspection, phase indicator
32
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
5.2 Equipment installation and wiring/connection inspection (1) （1）, （2） Insulation resistance measurement of cable between junction box and inverter panel Insulation resistance measurement of cable between inverter and interconnection switchboard Insulation resistance measurement of cables between interconnection switchboard, MCB and existing transformers ［Test procedure］ Measure the insulation resistance of （+，－） polarities and （R，S,T） phases of each cable to ensure that there is no insulation failure.
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
Measure the insulation resistance between each cable and the ground (according to code). ［Acceptance criteria］ 600V600V
e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
Power Conditioner-1～ ～ Interconnection switchboard >300V
R（ （red） ）
100MΩ or higher
S（ （black） ）
100MΩ or higher
T（ （blue） ）
100MΩ or higher
N（ （white） ）
100MΩ or higher
CV14sq-4C
Interconnection switchboard～ ～MCB R（ （red） ）
100MΩ or higher
S（ （black） ）
100MΩ or higher
T（ （blue） ）
100MΩ or higher
N（ （white） ）
100MΩ or higher
>300V CV100sq-4C
MCB～ ～Existing transformer-9
>300V
R（ （red） ）
100MΩ or higher
S（ （black） ）
100MΩ or higher
T（ （blue） ）
100MΩ or higher
N（ （white） ）
100MΩ or higher
CV100sq-4C
34
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
5.3 Equipment installation and wiring/connection inspection （1）、（2）
Insulation resistance measurement of cables between photovoltaic modules
［Test procedure］
Measure the insulation resistance of （+，－） polarities and （R, S, T) phases of each cable for one string of photovoltaic module array to verify that there is no insulation failure. Measure the insulation resistance between each cable and the ground (*The insulation resistance of the cable including the photovoltaic module will be measured).
［Acceptance criteria］ Open-circuit voltage≧300V： Acceptable if measurement using 1000V megger shows 0.4MΩ or higher .
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
Measurement of cable insulation resistance Module No.
Insulation resistance（ （M ）
Cable used
Result
Manufacturer’s standard type （4sq-5C） 1C ground cable, spare cable 2C
Acceptable
Manufacturer’s standard type （4sq-5C） 1C ground cable, spare cable 2C
Acceptable
Manufacturer’s standard type （4sq-5C） 1C ground cable, spare cable 2C
Acceptable
Manufacturer’s standard type （4sq-5C） 1C ground cable, spare cable 2C
Acceptable
Manufacturer’s standard type （4sq-5C） 1C ground cable, spare cable 2C
Acceptable
Junction box-1 PV1-1
+
65MΩ or higher
PV1-1
-
100MΩ or higher
PV1-2
+
100MΩ or higher
PV1-2
-
200MΩ or higher
PV1-3
+
150MΩ or higher
PV1-3
-
200MΩ or higher
PV1-4
+
100MΩ or higher
PV1-4
-
200MΩ or higher
PV1-5
+
50MΩ or higher
PV1-5
-
90MΩ or higher
Acceptable
Acceptable
Acceptable
Acceptable
Acceptable
35
5.4 Open-circuit voltage test/ground resistance test – example (1) （1）DC Open-circuit voltage of cables between PV modules The crystalline PV power generation system consists of 270 panels of 167 W module. Eighteen(18) modules in series ×fifteen(15) modules in parallel constitute a PV power generation system. The open-circuit voltage of one module is about 43.1V（at the highest）with an error of ±10%. Accordingly, the nominal voltage of one module accounts for 43.1V×0.9～1.1＝38.79～47.41V. The maximum open-circuit voltage of one circuit consisting of 18 modules will be:
e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
38.8V×18 modules＝698.22V （lower limit） 47.4V×18 modules＝853.38V （upper limit）
［Test procedure］ ・Measure the open-circuit voltage of one each string of PV module array to confirm the polarity of each circuit. ・ Measure the open-circuit voltage of one each string of PV module array to check if the number of modules in series is correct or not. ＜If the measured voltage is out of the acceptance criteria, the modules in series might be incorrectly connected.＞
36
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
5.4 Open-circuit voltage test/ground resistance test – example (2) （2）DC Open-circuit voltage of cables between photovoltaic modules ［Test conditions］ Tests shall be conducted during daytime hours on a sunny day. （Solar radiation shall be 0.1kW/m2 or higher.） ［Acceptance criteria］
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
Measure the open-circuit voltage of one each string of module array to confirm that it meets the following criteria. Measurement at junction box Module train No. Junction box-1
Acceptance criteria
Polarity （+， ，-） ）
Open-circuit voltage (Voc)
698V～ ～853V
PV1-1
O.K
744.0V
Acceptable
PV1-2
O.K
740.0V
Acceptable
PV1-3
O.K
737.0V
Acceptable
PV1-4
O.K
735.0V
Acceptable
PV1-5
O.K
734.0V
Acceptable
Junction box-1
37
5.4 Open-circuit voltage test/ground resistance test – example (3) （3） Earth resistance measurement ［Test procedure］ Measure the earth resistance. ［Acceptance criteria］
e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
Earth resistance of 100 or less is acceptable.
Ground resistance Item Interconnection point
Measured value
Result
1.6Ω Ω Acceptable
38
• Surrounding environment and anticipated damage
Falling leaf
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
Falling nuts
Stone throwing
e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
6.1 6.1 Some tips for system design (1)
Sand breeze Sand scratch (like frosted grass) Sea breeze Contamination Electrically grounding Animal bait 39
6.1 6.1 Some tips for system design (2) • Surrounding environment and anticipated damage Rain Lightning Lightning rod
e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
Strong enough for stormy wind
Heat up
Enough ventilation for cooling
Trench for heavy rain 40
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1 e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1 e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
6.2 6.2 Maintenance Plan for Photovoltaic Power Generation System (1) Monthly Inspection
Item
Content of Check
PV module
・Surface dirt & damage ・Damage of wire/cable ・Wire’s connection and damage
Support Structure for PV module
・Damage, rust & erosion ・Damage of wire/cable ・Earthing Conductor’s connection and damage
Junction Box Junction Panel
・Damage, erosion & rust ・Damage of wire/cable ・Earthing Conductor’s connection and damage
41
6.2 6.2 Maintenance Plan for Photovoltaic Power Generation System (2) Monthly Inspection Item
Power Conditioner unit
Instrument System
Display system
Content of Check ・Damage, corrosion & rust ・Damage of external wire/cable ・Earthing Conductor’s connection and damage ・Equipment’s allophone and nasty smell ・ Ambient temperature and humidity ・LCD indication ・Damage, corrosion & rust ・Damage of external wire/cable ・Earthing Conductor’s connection and damage ・Equipment’s allophone and nasty smell ・ Ambient temperature and humidity ・Check of Power Conditioners The numerical value that LCD of each Power Conditioner shows being about the same. ・Check of Monitoring System The power generation change according to Irradiance.
42
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1 e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1 e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
6.2 6.2 Maintenance Plan for Photovoltaic Power Generation System (3) Regular Inspection Item
PV module
Content of Check
Measuring Check
・Surface dirt & damage ・Damage of wire/cable ・Wire’s connection and damage
・Damage, corrosion & rust Support Structure ・Damage of wire/cable for PV module ・Grounding wire’s connection and damage
Junction Box Junction Panel
・Damage, corrosion & rust ・Damage of wire/cable ・Grounding wire’s connection and damage
・Insulation resistance Each circuit to PV in JB Each circuit to JB in JP ・VOC (Volt of Circuit) Each circuit to PV in JB Each circuit to JB in JP
43
6.2 6.2 Maintenance Plan for Photovoltaic Power Generation System (4) Regular Inspection Item
Power Conditioner unit
Content of Check ・Damage, corrosion & rust ・Damage of external wire/cable ・Grounding wire’s connection and damage ・Equipment’s allophone and nasty smell ・ Ambient temperature and humidity ・LCD indication
Instrument System
・Damage, corrosion & rust ・Damage of external wire/cable ・Grounding wire’s connection and damage ・Equipment’s allophone and nasty smell ・ Ambient temperature and humidity
Display System
・Check of PCS The numerical value that LCD of each PCS shows being about the same. ・Check of Monitoring System The power generation change according to Irradiance.
Measuring Check ・Insulation resistance Each circuit to JP in Inv. ・VOC Each circuit to JP in Inv.
44
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
7.1 Economical Effects ◆ Self-sufficiency of electricity supply and selling electricity - 100 kW Watt-hour system used Watt-hour value: approximately 95,000 to 115,000 kWh/yr Electric Power price: approximately 1,140,000 to 1,380,000 yen/yr
Fiji Islands 2-6, 2009 1--5, 2010 Republic of November Palau - November 1
e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
(Calculation is based on 12 yen/kWh.)
◆Conditions for example calculations 1. Conditions System capacity Annual expected power generation Installation expenses
100 kW 115,000 kWh/yr 70,000 thousand yen
General management ratio
10 %
Annual maintenance expenses
90 thousand yen
* Total capacity of PV array * Calculated based on simulation. * Purchase expenses are included.
* Large-scale repairs expenses are excluded.
45
7.2 Example Preliminary Calculations of Economical Effects 2. Preliminary calculations of investment effects 70,000 thousand yen (1) Installation expenses (2) General management expenses 7,000 thousand yen (3) Total investment amount 77,000 thousand yen
(1) × 10% (1) + (2)
(1) Preliminary calculation of power generation watt-hour as energy cost saving (4) Energy cost saving effect (5) Maintenance expenses (6) Effect Expected payback period
thousand yen/yr thousand yen/yr thousand 1,290 yen/yr 59.7 yr 1,380
* Calculation is based on electric power unit price of 12 yen/kWh.
90
(4) - (5) (3) ÷ (6)
e8e8/PPA / PPA DSM Workshop Solar PV Workshop Grid Connected
(2) Preliminary calculation for a reduction in demand Monthly basic price for business use Electric power capacity under (8) contract of an expected reduction in demand Energy saving effect (reduction (9) in demand)
(7)
(10) Introduction effects Expected payback period
Expected amount
1,690 Yen/ kW/month
* 20% of the installation capacity of 100 kW is expected.
20 kW thousand yen/yr thousand yen/yr 45.4 yr 406
1,696
(7) × (8) ×12 months (6) + (9) (3) ÷ (10)
(3) Preliminary calculation including environmental value (11) CO2 reduction (12) Effect of CO2 reduction (13) Total effect Expected payback period
63.8 tC/yr thousand 191.4 yen/yr thousand 1,887.4 yen/yr 40.8 Yr
Calculation is based on CO2 reduction unit price of 115000 0.000555 tC/kWh. ×0.000555 Calculation is based on CO2 trading rate of 3 thousand (11) ×3 yen/t. (6)+(9)+(12) (3) ÷ (13)
46
PV Hybrid system (Various type of power source)
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Grid Connected Solar PV Workshop Palau November 1-5,2010
Off Grid: PV hybrid systems within minimini-grid: Other power source: Genset Principle Diesel generator Continuous combustion -> Combustion gas -> Reciprocating motion -> Rotational motion by crankshaft
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Gas engine
Gas turbine
Continuous combustion -> Heat energy of combustion gas -> Rotational motion by turbine
Feature
Disadvantage
• High heat efficiency (35-45%) • Low cost • Rapid start-up • Automatic start/stop
• Vibration • Noise • Emission (NOx)
• Cleaner emission than DG • Smaller than DG • Available dual fuel system
• Vibration • Noise
• Compact and light weight • No cooling water • Good for rapid load change • Good starting performance • Possible no load operation • Small vibration
• Slow start-up than DG • Large fuel consumption • Large air intake and emission
2
• Fuel consumption vs output of diesel generator – High fuel consumption ratio under 50% output
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
160 100 140 76 120 56 100
Fuel consumption (%)
Fuel consumption ratio (%)
112
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Off Grid: PV hybrid systems within minimini-grid: Other power source: Genset
39
80 25
50
75
100 110
Output (%)
3
Off Grid: PV hybrid systems within minimini-grid: Other power source: MicroMicro-hydro
Features • Environmental friendliness • Clean energy contributing global warming • Short construction time and easy maintenance • Regional vitalization • Reduction of running cost at existing water facility • More reliable energy source than PV or Wind
Source: NEDO
4
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Off Grid: PV hybrid systems within minimini-grid: Other power source: MicroMicro-hydro • Utilize water flow and head (potential energy) – Generated power = gravitational-const. x flow x head • How to utilize water – Run-off – Reservoir (for seasonal operation) – Pondage (for daily operation) – Pumped storage • How to get head – Channel type – Dam type – Dam and channel type • Special type for Mini-hydro – Direct installation at gate/weir – Alternative to pressure regulator Source: NEDO
5
Off Grid: PV hybrid systems within minimini-grid: Other power source: MicroMicro-hydro Type
Feature
Flow control
Horizontal Francis turbine
Wide range in head and flow Installed widely from small to large scale Controlled flow by guide-vane, but expensive
Yes
Horizontal propeller water turbine
Good for small head No flow controller For seasonal change of water flow, multiple units installation is made.
No
Reverse pump turbine
Generation by reverse rotation of conventional pump Low cost, low efficiency
No
Source: NEDO
6
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Off Grid: PV hybrid systems within minimini-grid: Other power source: MicroMicro-hydro Type
Feature
Flow control
All-in-one submerged turbine with generator
Generation by reverse rotation of submerged pump with generator Low cost, low efficiency Need Access to machine by taking out from water
No
Cross-flow water turbine
For middle/small scale With guide vane Low efficiency degradation at small flow Simple structure, easy maintenance
Yes
Pelton turbine
Good for large head Installed widely from small to large scale Low cost, low efficiency Flow control by needle Expensive
Yes
Source: NEDO
7
Off Grid: PV hybrid systems within minimini-grid: Other power source: MicroMicro-hydro Type
Feature
Flow control
Turgoimpulse turbine
For medium/small scale Flow control by moving needle inside nozzle Low efficiency degradation at small flow Simple structure, easy maintenance
Yes
Overshot/ undershot water wheel
What we call waterwheel Not for generation because of low head and small flow, but good for monument Simple structure, easy maintenance
No
Source: NEDO
8
• Possible application Target flow
Target site
Flow
Head/Pressure
Others
River Channel
Mountain stream Mountain runoff Sand prevention dam
Torrent Large fluctuation Possible heavy flood
Easily obtainable head by steep slope
Suffering driftwood Risk of banking sand, landslide or water disaster Maintenance of river system
Hilly area, highland, Slope section of flat land or water intake facility
Fluctuation Possible of flood/drought Flow-down of garbage Possible water pollution
Hard to obtain large head except for heavy slope
Near to demand area Limitation of usage by flood/drought Necessity of dust removal Maintenance of river system Environmental friendliness
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Off Grid: PV hybrid systems within minimini-grid: Other power source: MicroMicro-hydro
Characteristics
9
Off Grid: PV hybrid systems within minimini-grid: Other power source: MicroMicro-hydro • Possible application Target flow
Agricultural water
Target site
Characteristics Flow
Head/Pressure
Others
Main line Channel Water pipe line
Large difference in flow between irrigation season and non-irrigation season
Hard to obtain large head by low-gradient
Depends on height of end-point
Sub line
Difference in flow between irrigation season and nonirrigation season
Control point of flow, pressure and inclination
Fluctuation of intake by agricultural field Flow-down of garbage
Necessity of dust removal Maintenance of river system Environmental friendliness Easily obtainable head, but maybe small head
Modification or improvement of existing facility
10
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Off Grid: PV hybrid systems within minimini-grid: Other power source: MicroMicro-hydro • Possible application Target flow
Target site
Characteristics Flow
Head/Pressure
Others
Industrial and daily life water
Water transmission line
Relatively constant flow
Easily obtainable head by remote demand area from source
Possible water pipe
Industrial effluent and sewage
Discharge channel
Easily obtainable of constant flow
Depends on tail water level
Water quality Emergency stop by facility trouble
In-house supply and drain water system
Supply and drain water channel
Stable Various flow quantity depends on production process
Utilization of regulated and surplus water pressure Easily obtainable head or pressure
Necessity of consideration about harmlessness against primary water use
11
Off Grid: PV hybrid systems within minimini-grid: Other power source: MicroMicro-hydro • Example of direct installation Gate Generator
Example of installation at sand prevention dam
Water intake
Sand prevention dam Water channel Generator house
12
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Off Grid: PV hybrid systems within minimini-grid: Other power source: MicroMicro-hydro • • • • • • • •
Egasaki control room, Water works dept of Kawasaki city Water source: Piping for city water Purification Utilization of head at water piping plant Head Max available head: 36.09m Water flow Horizontal propeller hydraulic turbine (2 sets) 3 Water flow: 0.6m /s Output: 170kW(max), 90kW(normal) Existing pressure regulator Expected energy generated: 540,000kWh/year
Generator
Distribution reservoir
Source: Kawasaki city
13
Off Grid: PV hybrid systems within minimini-grid: Other power source: Biomass energy
Features • Stock-able fuel • Clean energy – Carbon neutral – Low NOX and SOX emission – Carbon dioxide absorption via tree planting • Renewable energy to realize recycling society • Contribution to job creation and/or industry revitalization • Vitalization of agricultural community
Source: NEDO
14
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Off Grid: PV hybrid systems within minimini-grid: Other power source: Biomass energy Biomass resources Unutilized resource
Woody material
Remaining materials at forest land, thinned wood, unused tree Remaining material of lumbering, scrap wood from construction, others
Paper
Used paper, sludge from paper production, black liquor
Agricultural residue
Rice straw, rice husk, straw, bagasse, others
Night soil, dung and sludge
Cow dung, pig dung, chicken dung, others
Leftover food
Sewage sludge, sludge from night soil purification Waste from food processing wholesale market and food retailing Kitchen waste from home and restaurant Waste cooking oil
Others Productive resource
Landfill gas, waste fiber
Woody material
Short cycle cultivated lumber
Herbal material
Grass, waterweed, see grass
Others
Sugar, starch, palm oil, rape oil 15
Off Grid: PV hybrid systems within minimini-grid: Other power source: Biomass energy Biomass processing Thermo chemical conversion
Direct combustion gasification
Molten gasification Partial oxidation gasification Cold fluidized bed gasification Supercritical water gasification
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Liquidization
Fast pylolysis Slurry fuel
Carbonization Esterification Biochemical conversion
Methane fermentation
Wet process Dry process
Two-stage fermentation Ethanol fermentation
16
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Off Grid: PV hybrid systems within minimini-grid: Other power source: Biomass energy Direct combustion system for woody material Silo
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Lumber mill
Scrap wood
Power to factory load Power to other load Turbine/ generator Boiler
Source: NEDO
17
Off Grid: PV hybrid systems within minimini-grid: Other power source: Biomass energy Gasification generation system for woody material Hawking unit Gasification unit Slide gate Electric cylinder Engine generator
Belt conveyer
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Gasifyer
Rostle oscillating unit
Electric valve
Heat recovery unit
Electric valve
Electric cylinder
Waste gas combustion unit Bypass Control panel
On/Off signal
Automatic igniter Propane gas bottle
Auxiliary panel Source: NEDO
18
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Off Grid: PV hybrid systems within minimini-grid: Other power source: Biomass energy
Typical example of furnace
Rotary kiln
Source: NEDO
Stoker furnace
19
Off Grid: PV hybrid systems within minimini-grid: Other power source: Biomass energy Yagi bio ecology center
Yagi bio ecology center
Fermenter, gas holder
Generator Source: NEDO
20
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Off Grid: PV hybrid systems within minimini-grid: Other power source: Biomass energy Yagi bio ecology center Digestive gas
Frementer
Cow dung, pig dung, straw, sawdust
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Bean curd refuse Gas holder
Receiving tank
Liquid fertilizer
Digestion Digestion tank bath
Hydro extractor
Surplus gas combustion
Dehydrated cake
Raw water tank Compost Gas holder
Hot water boiler (backup)
Hot water
Waste water treatment (Existing)
Power
Waste water treatment
Desulfer ization Digestive gas
Generator Digestive juice
Effluent to river
Frementer
Digestion tank
Reuse Source: NEDO
21
Off Grid: PV hybrid systems within minimini-grid: Other power source: Wind power
Features Clean energy – No carbon dioxide emission Domestic energy resource Renewable energy Most economical among new energy resources Stable generation cost Awareness for energy and global warming issue Contribution to local region Source: NEDO
22
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Off Grid: PV hybrid systems within minimini-grid: Other power source: Wind power Up wind
Horizontal axis
Propeller Down wind Horizontal axis
Sail wing
Propeller
Sail wing
Lift type Holland type Multi-bladed Holland type
Windmill
Multi-bladed
Vertical axis
Darrieus
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Lift type Straight wing Vertical axis
Sabonius type
Darrieus
Straight wing
Puddle Drag type Cross-flow
Sabonius type
Puddle
S-shaped rotor Cross-flow
S-shaped rotor
Source: NEDO
23
Off Grid: PV hybrid systems within minimini-grid: Other power source: Wind power Type
Feature
Horizontal axis
Simple structure High efficiency Easy to scale-up Good for generation Need yaw control for up-wind type Heavy load exists in nacelle.
Vertical axis
Not depend on wind direction Heavy load exists on ground. Easy manufacturing of blade compared to propeller Hard to control rotation speed Need large torque in start-up Lower efficiency rather than horizontal axis type Large footprint
Lift type
Good for generation by higher peripheral velocity than wind speed Less blades has higher peripheral velocity
Drag type
Many application in small scale Large torque Peripheral velocity is less than wind speed Good for pump-up and grinding flour Lower efficiency than lift type Source: NEDO
24
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
Off Grid: PV hybrid systems within minimini-grid: Other power source: Wind power
Blade
Anemovane Nacelle
Hub Generator
Console Report
Drive train axis Rotor axis Brake system
Fiji Republic Islands ic ofNovember 2-6, 200911--5, 2010 Republ Palau - November
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Speed-up gear
Distribution line Tower
Protection system
Display board
Power conversion system
Transf ormer
Communication line
Controller Power pole
Foundation
Source: NEDO
25
Off Grid: PV hybrid systems within minimini-grid: Other power source: Wind power 3 phase AC (power freq.)
Speed-up gear Rotor (fixed speed)
Induction generator
(a) AC link (Induction generator)
3 phase AC (control freq.)
3 phase AC (power freq.) Converter
e8 / PPA Grid DSMConnected Workshop Solar PV Workshop e8/PPA
Monitoring system
Yaw drive unit
Speed-up gear Rotor (variable speed)
Induction generator
Inverter
3 phase AC (power freq.)
(b) DC link (Induction generator) 3 phase AC (control freq.)
DC
Synchronous Converter generator Rotor (variable speed)
3 phase AC (power freq.)
Inverter
(c) DC link (Synchronous generator)
Source: NEDO
26
