Unit 3 and 4 Solar-Passive-Architecture

PASSIVE SSIVE SOLAR ARCHITECTURE

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SYNOPSIS Introduction • •

The need Importance of energy conservation in buildings Pattern of energy consumption

Aim Objective Methodoo!" So#r P#$$ive Techni%ue$ •

Passive heating   

Direct gain Indirect gain system Direct gain systems 2

SYNOPSIS Introduction • •

The need Importance of energy conservation in buildings Pattern of energy consumption

Aim Objective Methodoo!" So#r P#$$ive Techni%ue$ •

Passive heating   

Direct gain Indirect gain system Direct gain systems 2



Windows

 Glazed Wall

Glazed Atrium 

Indirect gain systems    

Roofbased air heating system Thermal storage wall system s ystem !Trombe wall" Water wall #un spaces Transwall

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Passive cooling 

Passive cooling systems           

$entilation $entilation % &perable Windows Wing Walls Thermal 'himney &ther $entilation #trategies Passive Downdraft (vaporative 'ooling !PD('" #ystem (arth berming (arth air tunnel !(AT" system 'ooling Tower ) Wind catcher ) Wind Tower (vaporative cooling Roof pond system 'ourtyard

C#$e Studie$ • •

*+P+ #TAT( '&&P(RATI$( ,A-. ,/I0DI-G1 #*I20A I-#P('T&R G(-(RA0 &3 &3 P&0I'( !IGP" '&2P0(41 G/0,ARGA T*( R(TR(AT '&2P0(4 &3 T(RI AT G/RGA&- I- *AR5A-A

Concu$ion$ Re&erence$

Introduction Passive Passive solar architectu architecture re is an ancient ancient concept+ 2odern 2odern science science has provided 6uantitative 6uantitative support to ascertain its effectiveness+ #olar passive architecture has large potential for energy conservat conservation ion and can lead to a thermally comfortable comfortable indoor environment+ environment+ It is defined as collection1 storage1 distribution and control of energy flow by natural processes of heat and 3

mass transfer+ Its wor7ing definition is  use of natural energy !sun1 wind1 etc+" to conserve conventional energy for achieving thermal comfort+ Thermal comfort refers to comfortable indoor conditions !temperature1 humidity1 air movement"+

The need

,uildings1 as they are designed and used today1 contribute to serious environmental problems because of e8cessive consumption of energy and other natural resources to construct a building % meet its demands for heating1 cooling1 ventilation % lighting which causes severe depletion of invaluable environmental resources+ #tudies show that residential and commercial sectors in India together account for 9:; of the country the cooler air comes in contact with the bottom of  the tower through the roomsJ it gets heated up by the warm surface of wind tower  and thus an air flow is maintained in the reverse direction+

 A combination of sensible cooling in the ground and evaporative cooling with the flow of  air induced by the wind catcher+ Wind towers with indirect evaporative cooling systems have been integrated with *$A' system for precooling fresh air+

Limit#tion$

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+'oncepts of wind catcher can wor7 well an individual units of house and not in multistoreyed building+ 9+In a dense urban area the wind tower has to be very high to be able to catch enough air+ ?+The surface of the wind tower accumulates dust and heat transfer from the surface of wind tower to the air becomes slower+ +If the wind direction is unpredictable1 it is better made openings of the inlet wind catcher on all four sides+

Wind Tower #%aporati%e "ooling 

#%aporati%e "ooling Tower 

Ev#'or#tive cooin!

(vaporative cooling lowers indoor air temperature by evaporating water+ It is effective in hotdry climate where the atmospheric humidity is low+ In evaporative cooling1 the sensible heat of air is used to evaporate water1 thereby cooling the air1 which in turn cools the living space of the building+ Increase in contact between water and air increases rate of evaporation+ The presence of a water body such as a pond1 la7e1 sea etc+ near the building or a fountain in a courtyard can provide a cooling effect+ The most commonly used system is a desert cooler1 which comprises of water1 evaporative pads1 a fan1 and pump+ (vaporative cooling has been tried as a rooftop installation solar energy centre1 Gurgaon+ *owever1 the system has now become defunct due to poor water supply in the area+

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Roo& 'ond $"$tem This system can provide both heating and cooling+ B9 inches of water are contained on a flat roof1 usually stored in large plastic or fiberglass containers covered by glazing+ During the cooling season1 an insulated cover is removed at night to e8pose the water to cool night air+ The water absorbs heat from below during the day1 and radiates it out at night+ The temperature within the space falls as the ceiling acts as a radiant cooling panel for the space1 without increasing indoor humidity levels+ During the heating season1 the insulated cover is removed during the day+ The water absorbs heat from the sun1 and radiates it in to the building below+ In cold climates such as ours1 an attic pond beneath pitched glazing is more effective than a flat roof pond+

The limitation of this techni6ue is that it is confined only to single storey structure with flat1 concrete roof and also the capital cost is 6uite high+ Roof ponds re6uire somewhat elaborate drainage systems1 movable insulation to cover and uncover the water at appropriate times1 and a structural system to support up to B:lbs)s6 ft dead load+

Roof pond  cooling 

Roof pond  heating 

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Court"#rd Princi'e o& the court"#rd( Due to the incident solar radiation in the courtyard1 the air in the courtyard becomes warmer and rises up+ To replace it1 cool air from the ground level flows through the openings of the room1 thus producing the air flow+ During the night1 the process id reversed+ The cooled surface air of the roof sin7s down to the court and this cooled air  enters the living spaces through the low level openings and leaves through higher level openings+ This system can wor7 effectively in hot and dry climates1 where day time ventilation is undesirable1 as it brings heat inside and at night the air temperature becomes cooler and it can ventilate the building+

&odel of courtyard  house

Limit#tion$

+When the courtyard receive intense solar radiation1 much heat will be conducted and radiated into the rooms as against the induced draft of air which may be problematic+ 9+The intense solar radiation can produce glare for the inside room+ The best way is to 7eep the courtyard shaded and only partially open to s7y+

C#$e Studie$

H3P3 STATE CO.OPERATIVE 4AN5 4UIL)IN,6 SHIMLA

Loc#tion ( #himla1 *imachal Pradesh Cim#te ( 'old and 'loudy

4rie& de$cri'tion o& buidin! (

This building is a ground and threestoreyed structure with its longer a8is facing the eastwest direction+ The smaller northern wall faces the prevailing winter winds from the northeastern direction+ The building shares a common east wall with an ad=oining structure+ Its west faOade overloo7s a small street from which the building draws its main re6uirements of ventilation and daylighting+ A plan and section of the building showing the various passive techni6ues incorporated is given below+

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Section and plan of $. !. state co'operati%e ban() Shimla Ener!" con$ciou$ &e#ture$( • •

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• •

•

#outhfacing Trombe wall and sunspace heats up the interior+ #outhfacing solar collectors on the roof provide warm air1 which is circulated by means of ducts+ -orth face is protected by a cavity wall that insulates the building from prevailing winter winds Western wall is provided with insulation as well as double glazing+ Daylighting is enhanced by providing light shelves+ #7ylight on the terrace also provides daylighting+  Air loc7 lobbies are provided to reduce air e8change+

Per&orm#nce o& the buidin!( The predictions of the energy savings of the building !componentwise" per  annum1 as compared to a conventional building are as follows> 23

West wall !double glazing and insulation"  ?9C 7Wh Roof insulation  9?EB 7Wh Roof top solar collector  @9EC 7Wh Trombe wall  E?C 7Wh Total  CE9@ 7Wh

INSPECTOR ,ENERAL O7 POLICE /I,P0 COMPLE86 ,UL4AR,A

Loc#tion ( Gulbarga1 .arnata7a Cim#te ( *ot and dry 4rie& de$cri'tion o& the buidin!( This building is a ground and twostoreyed structure designed by .embhavi Architecture 3oundation to house the offices of the Inspector General of Police1 Gulbarga+ The building is constructed using innovative materials+ 3or e8ample1 the e8ternal walls are composite walls !i+e+ granite bloc7s on the outer side and rattrap bond bric7 walls on the inner side" and the roof is made of filler slab+ The /values of the walls and roof are +:? W)m9. and 9+: W)m9. respectively+ The building is roughly rectangular with the longer a8is along the northsouth direction+ 2ost windows face east or west+ A layout plan of the building is given+ As the building is located in a hot and dry climate1 evaporative cooling has been used for providing comfort+ 2ost of the offices are cooled by passive downdraft evaporative cooling !PD('" tower system+ 3igure below shows a photograph of the building as well as a s7etch section of a typical PD(' t ower to e8plain its principle+

Ener!" con$ciou$ &e#ture$( • • •

*ayout plan of +.G.!. "omple,) Gulbarga

Passive downdraft evaporative cooling !PD('" towers for providing comfort+ Tinted glasses to reduce glare+  Alternative building materials such as composite walls to reduce heat gain and filler slabs to

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• •

reduce the 6uantity of concrete in the structure+  A central atrium to enhance cross ventilation and provide daylighting+ #olar P$ lighting and pumps1 rainfall harvesting and water conservation facilities incorporated+

Per&orm#nce o& the P)EC $"$tem( The building is in the final stage of construction+ The PD(' system 9C o' and humidity at : F :@; !when the ambient temperature is about @ o' and humidity ?@;"

Economic$( The incorporation of passive solar features in a new house will not normally re6uire e8tra e8penditure+ The houses under consideration can be divided in three main categories> +

*ouses where choice of proper orientation and site planning and efficient functional planning is possible1 energy efficiency can be achieved at no ma=or e8tra cost+

9+

*ouses for which there is less availability of sunlight1 less independence in selecting the site and orientation1 there is an increase of only :@; in cost which may be re6uired for greater levels of insulation1 special heating and cooling re6uirements+ *owever1 due to lesser fuel ) electricity consumption year round1 this incremental cost can be recovered in : F E years+

?+

*ouses which are to be retrofitted with space heating solar passive systems li7e Trombe wall1 sun space1 space for heating of green houses1 adding insulations will re6uire e8tra funds+

/nli7e fossil fuels1 solar energy is available =ust about anywhere on earth+ And this source of energy is free1 immune to rising energy prices+ #olar energy can be used in many ways F to provide heat1 lighting1 mechanical power and electricity+

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P#$$ive hou$e

The dar7 colours on this thermogram of a passive house !right" show how little heat is escaping compared to a traditional building !left"+

Re&erence$(

2anual on solar passive architecture> energy systems engineering IIT Delhi and #olar (nergy 'entre1 2inistry of -onconventional (nergy #ources1 Government of India1 -ew Delhi"

,ansal - .1 *auser G1 2in7e G+ Passive building design> A handboo7 of -atural climatic control+

-aya7 Q .1 *azra R+ Development of design guidelines by laws+

Thomas A 3isher+ 9  AIA1 -ovember 9

T(RI report BRT Window design optimisation

2azria (+ E The Passive #olar (nergy boo71 Rodale Press1 Pennsylvania

0evy 2+ (+1 (vans D+1 and Gardstein '+1 The Passive #olar 'onstruction *andboo71 Rodale Press1 Pennsylvania1 C?"+

http>))www+tt+fh7oeln+de)semesterpro=ects)la7e;9@nasser;9@@?@)*ouse;9@Plan)$entilation;9@and ;9@cooling+pdf 

http>))www+ese+iitb+ac+in)events)other)renetfiles)9)#ession;9@?)passive;9@solar  31

;9@architecture!Q+.+-aya7"+pdf 

http>))www+ese+iitb+ac+in)events)other)renetfiles)9)#ession;9@)Design;9@guidelines;9@for;9@energy ;9@effcient;9@building!;9@Q+A+Pra=apati"+pdf 

http>))boo7store+teriin+org)docs)boo7s)Introduction;9@energy;9@eff;9@biuldings+pdf 

http>))www+technopreneur+net)technology)-ewtechnologies)(nergy)buildings+htm

http>))en+wi7ipedia+org)wi7i)PassivesolarbuildingdesignSDirectsolargain

http>))mhathwar+tripod+com)thesis)solar)solararchitecture+htm

http>))www+nmsea+org)(ducation)*omeowners)passiv9+gif 

http>))www+smarterhomes+org+nz)design)glazing)doubleglazingglassoptions)

http>))www+wbdg+org)resources)psheating+php

http>))www+azsolarcenter+org)techscience)solararchitecture)passivesolardesignmanual)passivesolardesign manualheating+html

http>))www+building+co+u7)Pictures)web)n)l)m)?prodsT('*-A0TA-AT&RI24#+=pg

http>))www+reidsteel+com)images)dsc@+=pg

http>))www+sustainablebuildings+org)inde8+phpoptioncomcstudy%tas7details%sid9

http>))www+learn+londonmet+ac+u7)pac7ages)clear)interactive)matri8)c)coolperiod+html

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