MICROFICHE -REFERENCE iL LIBRARY 4 project of Vol&te& in As,ia s\: 1 31 rO \ .@&* / by: Edward Mazria Published by: .. I ' Rodale Pfess, Inc. " 331East Hinor Street Emmaus, PA 18049 USA Y Pqper @bpies are $12.95. .4 '. .Availa.ble from: r. .-Qi x Rodale Press, Inc. ,,' r,- .,'33 East Minor Stgeet I,,~ --A -' ., 'F mmaus., PA' 180-49- USA I__' “ir?: Reprodu'ced by. permlksion of the, Rbdale Press. , i ,.$ r -.: _1 . e. ~~~~ti~~of~~thlsrniclrnf~~~dournen~ -in ay 2 '$,;,;~-1 'form is subject to the same restrictions as'khose. J ,pf ykie origin~ocbment. : 9 ,..I.' t . .- \ . .. A Dr all of the4nforhation nece$saG. tq successfully.d.qign an’effective ~- -~~ -- - -.~ -~ ;: _. -::,7;I C , ; , +, I~ ,I .- .-;- .tt is’: z, A ; -,d . A prim&- i -.‘I in the fundamental concepts of s”olar energy, heat I, 1 ~.~-..- _~--~- L&&fort. ~ _\ --. ~. __-- - ~-...- .- .- ... -; - ~--~- --~_< _ ,.p~evgjuzfb~ thesaulof passiYearch&nB. - .-_-. ------ -------i-L i , .&mmake-it-wyrk;for-you. --.- ~1. v ,.Fp _ ’ FredNelson,S&et .y; \., ... .I The best book tie Ii&e seen on passive solar. b;il&ngs becau:e-it makes the O .*- fundamental,.r&isons why su,ch buildings are highly desirable so crystal : “, t - clear. And, once you really understand the fundamentals Qf any suI+ct, the ‘; D c . Drest iSeasy. , I .; , > ,,’ William 8. Edmondson,Ed?tor,SolarEnergyDige&-~--~? I -- -----; 3 . -’ fq%&+~ overcrowded,field. . ’ \ ~\,--~-- I -m--y *” L :LeeJohnson, Editw, RAIN: Fo”~~?alpf A.ppropriateTechnology .: : _ ,‘.. -.. .’ i ; ‘“;,...ji>.9’; Q-G, cgver:design and ii[ust&kjns’ by f&&&i Ball * ’ b!,.;‘:.;.,,-;y;t.1:.-.. . !‘,..” ,* ,. ,:--y&; . * L047@7-237,6 %.$.* , . J . I t I. . ‘b.’,., ,, ..-* 0 I -. .- \-.\,A “* -L:aa,.- .\ ‘3’ , k. I s L7 ..;.“.g . : __-- ,_-. 4 3 - 3 > Y /’ ;’ BY EDWARD MAZftlA F--i71. . ..:-.. .” i’ Copyright @ 1979 by Edward Mazrja , All rights reserved. No part of this publication may be reproduced or transmitted in any form{ or by any -“’ *I means, electronic ‘or mechadical,‘.includrng photocopy, recording, or any. information storage and retrieval system without the written permission of the publisher. ‘ S’ L , f3ookDesign hy 7 A lcpley * ” -.\ .. The passive solar energy book. L \ 5 .’ Bjb;liography:. p. ‘_ Includes index, , I . \ 1. Solar energy~ 2.‘Solar heating. I. Title. ‘\ TJSiO.M32 1979b 696 78-21656 ’ ISBN,O-87857-260-0 (Hardcover) I$ BN O-87857-237-6 (Paperback) 4, 8'10 9 1 hardcover L 12 14 16 18 20 19 17 15 13 11 paperbdck \ .-_ 3 Printed in the United States of America on recycled paper, containing a high percentage of de-inked fiber. F _. I . i* . ., 0= : .’ :, . .(” ., .-.. Library of Congress Cat+l&ing’in Publication Data 3 Mazria; Edward. \. <. . . 4 . 65 ‘. .I..-- . 4 - I 3; . . ‘, : ---L!h*,* P ~ _..-.-. _. .i. .y ,1. ” * ..I.:.*. _I. 7 -: ‘I ’I yzj , I. :: _ * *. ‘-S= - * .# -*II -. . i--.‘ -- P 1_ ’ ,,- . - P’ P AP .‘.; - 0 + ‘_. > : ,‘I,- L ,” 3 91 ., -. / 1,-c,_ - * . J.. “l ‘. , “; ye . I . . L ‘i ,_-_. - l . *’ : I . * : . .” ;,A.. -A . . . __,,_. _a :... Or 1~ -I.-. ‘)-- .-- . -- --_ _ 5. : 1; c * ,.. _..- ___.__ -_I--. .- __._..-_-. -..- f . . / :‘;j .’ ” l s i ,_ I .. \. .*zi . * I ^ \ . ,,. t’ 1 For JOSEPH and $RA ’ .’ ! . .’ . I ,. a , * 0 . -6 0 0 . z -. --v-f, i_ “2 . 0 a .~ . ~ . ~ --~--. ~_ m c I’ :i /‘\ \. ,,, .i.. : F .i ,‘e ‘: .. 0. ‘I_ L ‘, .” - ) 1 4 . .* ;, . \ m t. .h . [ ” - & ,. ( 1 ‘.< * ( 3 ** .;j? * ;,.; .‘I, I 0 : 8 a. ’ . - 0 ‘ - I * -. . , Y 1 L : *. ,h ’ c -. - L.. . - _ ,t II . . IV;_ Using the Patterns _ -_ . ! , cp The Passive Solar Energy Book l i’ ‘. i -. - 9 . $i- p.’ : - -. Y ‘ a -. .’ , ,; -. * ” *ar i’ , r _ _ -. -,--. ( , , -- Direct Gain Systems 9. SOLAR WlNDg>WS c “, 10. CLERESTORIES AND SKYLIGHTS 11. MA&ONRY HEAT STORAGE ,- ---- \ _32- JNIERLOR. WATER -WALL- . Thermal Storage Wall Systems’ 13. S[ZIbk THE WALL ’ ce. i4. WALL DETAILS ’ ., I Attach%d Greenhouse Systems \ 15. SIZING THE GREENHOUSE 16. GREENi-lOuSE CONNECTIONp L .>\\ “%1I 8 t i 24 153 B * -I$‘14 - -i \ ‘_ 152’,\ ’ 158 172 .,- 180 Robf Pond Systems 1 bj K,enneth 1. Haggard and PO//Y Cooper 17. iZING THE ROOF POND’ I , 186 18. ROOF POND DETAILS 193 I. 1 Greenhouse . ; , 19. SOUTH-FA~NG GREENHOUSE 20, GREENHOUSE DETAILS 200 ’ .- 208 . :, 21. ,dXMEitilNC SYSTEMS ‘22. CLOUDY DAY STORAGE 23. MOVABLE lNSU\+TION 24. REFLECTORS ?, 25. SHADING DEVl‘i3ES ., 26. INSULATION ON THE OUTSIDE 27. SUMMER COOLING ---219. ~- --‘2i5 230 249 ‘* 258 262 V. The Sun Charts--how the sun works, the cylindricdl 267 THE TOOLS ~ sun chart, sun charts, sun time, plqtting the skyline . . . The Solar Radia’fion Calculator--hourly radiatiov . 293 6 totals, daily radiation totals, splar I intensity masks ’ ‘The Shading’calculator-p/ot’tirfg the sha$ng mask 301 ; .d -I I ’ \(I ... Vjll ; y. :\ . -. ‘. ;) 6 . ‘V , /I ; , .-:. ./ -‘. 11. I > ., / */ . \t n3 _” r? Table of Contents ., w \” 0 --.-’ -- . . . . 1. Perfocwa+ce Calcblations ’ 2. Percentaie of Solar Radiation Absorb&i ,4/./. ,/,;I =..>, )A&* ,’ ./- by Various Sdrfacqs, . )I, :y -2. 3. Averqhe Daily Sol/wRad~iak5~ ’ + -3. r, ‘. i ““2_.,- &ASeI$ge Daily Te/nperattires (“Fj in North / :u _.~ i ; --_-_- 1 ..- \ ’ Amqkica -‘- j . d I ii -~--I Ij* _,.,_._ ..t.,.. “,. . I i “, &jree-D.ays _,.,:.,. .,. .:.. _ .*r- ....-. -.-l- ’ 7 - - -.__ .~-_.. -__-.-- .._. _ .JY- A--_ . .‘~~-,. p-.--... - ----l- 6; -f&@r-&++%m’ ~1- ’ __ _ ___- - _--.,.__ -- ._~.._~ 1..___ : =* I * 7 l , 7. Pqcentage of Ehhanceknt of Solar. H&t I @in with Speclillarf$flectors .* . 8. -C nveision Table’s 9 ., JOGRAPHY i /’ f 5 ‘h.. , ” : A r’ 1.‘. . ‘a, I ’ ; . ..I I ; \,~,, ,A’ 0”; y.” \ ” _-- -- \ , . -. ,; : y* ac . .. 309’ 345' \ . '\ 346 * ; 360 ; :-'=/ I. 372 .,.T‘ . .I+ ...-, - '.4m.e- - p-- A,;-. 4ili, i \\ t iv,. . +a, 408’ f’ * _.. ;A \ - iu^ I. . s 426 * ,/ . 0 Y @.‘.” . .. . Ackno@edgments - -‘- i 0 .I .. vi .7.. . . Four years *igo, when .I kegan writing this book, information concerning ” passive solar heating was,virtually nonexistent. During this time many fri ds have worked with ‘me to generate portions of the information in ihe text. Their work and’assistance made the scope of this book possible. -I want to especially thank: ....,. J I I ;;,( ‘./ ” __ I ‘\ ‘ ‘I I ,J’ Steve Baker who”‘worked”closely withme for t.wo years to genera!e. data *for the- formulation of the patterns and’ calculation p.rocedures. His ’ i;-iii - %tsight and kno-w.ledge of’the subject add a dinet$ion to, the book that .‘- I would otherwise be-absent. I am grateful not only for his contribution to the book, but for his support,and friendship during iti. production. )I ,.- _; I j. A * .1 :* ,I’i._ Robert Young who spent numerous hours assembling the .Appendix, ..\$~, i I z producing the technjcal drawi.ngs and photograiphing,many of the build-. >!,’ 0 1 -ings.presented .in the book. . y. / Ir i 4 - .. Raymond Har@;n.$ho gave generously of his time, at the conception ,. ’ ’ ’ of the-hook, to answer my seemingly endless questions about solar energy I -, . f c;:-.. .~~1.’ ., ~ an~d.he&transfer, .. _~~ .s b .I : \ - ., h j ‘dL _r / $;, -- ,, x ‘.,, ,\ ’ .’ ,- I ,, ‘’. .L . i-- . ,;.. ‘,,, i ~ / -, . ,, ,;Q , I.* .. . ;,,‘.,1 ,_ i-+- :i ,.’ :’ ! o / -h * i, 4 ~-. ‘, -..1 2g:::;:,,&:,I~\?~;”’ ;-- ,!” , : , 1 ,2 r Acknowledgments h-Haggard and Polly Cooper (of their patterns onr’oof ponds. /. . 4.. i oh Cettings’for his beautiful photographs. I. - P. : &&“l’Stone~ fbr’her early and c . eagement. _ i&&a H&&n for be$&&qre wh%& t&going G&?isugh.. -- -* b . ’ . P.F n&to MA?Rfi for p;oviding a supportive environment. I _ 7h.-‘_ >c .. 4 1 * . Thei.conti.nuing support of, many -friend.q ,&heir confidence in me and patience i inade.it all,possible: Joyce Brown, Bonnie Katz, Aaron Mazria;,Gary Goldberg, David Tawif, Jim Greenan, Larry Keller, Charlene Cerny, KantFowitz, Barbara.Levy, J. Douglass and Sara Balcomb, Nichols, Rosalie Harris, Carol Bickleman, Boyd B&&it&m Tim Zanes, Peter Calthorpe, Jim Van Duyn, Eric Hoff and Richard ~-~~ CT in the text .is modeled after “The Pattern Language” by Christopher Alexander, Center for Envi’ronmental Structure, . ,’ .. xi ;.‘..“. ,. J ‘.j ,-::” .. .: , > ... - : . . . Ii. known for his c$inmercial.d~~ign~,-j-jltmtrations ,. <__ ,’ r I . . 0 has been art dire&r 6f three’mhjor &ertising ~. / 1s~pr,ints~ and paintings are shown i-n galler’ies ‘* \ c United. States. Since the illustrations for this bodk ’ L : technical information clearly and precisely, as Ily appealing, the illustrdtor and author “have ’ gether throughout the four years of the boo,k’s \, dqelopmen t. t, - ,$ .. ” 9_ . i* ‘. I I -‘ c *’ ,. I (’ 1 X..II. ..rl,lb \ . . d :... -. - I , / _3, ( ._, _I. . .,1. ;.. -7 ; ,.;; . . , I, . . -a v 1 , I , ..:) .*/ : * building that is strongly related to* site, climate, local buildid) m,aterials ,and the>sun. It implies a,,specMI.relatio~ship to natural’psocesses that offers the potential for an inexhaustible’supply of vital energy. This attitude is obviousjy j not entirely new, since much vernacular architecture has always reflected a . . strong relationship to daily and seasonal climatic and solar variations:In recent years, however, relying on the misconception of an infinite and inexpensive energy suf~ply, people have choseen t siderations. P abandon these Ion&standing con-’ .f.; II / I ‘\ .I Architecture in the twentieth century has been characterized by an emphasis on technology to the exclusion of other’values. In the built environGment this concern manifests‘itself in *the I materials we build with, such as plastics and synthetics. There is an existing -dependknce’ on mechanical control of the indoor enviro?ment rather than exploitaeion of climatic and other ,natural processes to satisfy our comfo~rt -prisoners of complicated mechanical nts. In a ,sense,, we have become since windows.must be inoperable and sealed in order for work. A minor power. or equipmenf failure can ,make these buildings uninkabitable. Today, little.attention is paid to the unique ch’aracter and’variation of local climate and building materials. One can now see essentially the same type building from coast to coast. 1 4 4. Today, there is a strong, new interest in passive solar heating and cooling systems becaus,e they simpjify rathe+r than complicate life: Passive systems are simple in concept at-ii. use,-.ha\Re few moving parts and require little or no maintenance. Also, these systems do not generate thermal pollution, since they I ‘4 fl .*-a 1, *.! ,. t .A ? * I -_, - ‘Z ! -r . 1 1. -..---I -r- ~~- --~ I-‘a h , - t ‘5> .. -’ ,, .The Passive Solar Energy t$Dok P i- t I’ , * CI 1;1 t . dAm” -. P . F require ho external energy input and produce no p‘hysical by;products or waste. ; f :, .~ Si.nce solar,energy is c0nyenientty.distributed.b alI’pa$+ of the globe, expen‘sive transportation and, distribution netwolk$ of energy are also eliminate.dd. * #\ .A \ .I Jr.k-t ; r Shce a buildi’ng’or some element of it is the passive system’; TheAappllcatipn 5 of passive solar energy must be included in every step of a buildings design. ,.,_. +eWhereas conventional or a-ctive solar-he.ating’iystems can!be s6mewhat independent d’f the conceptual organization of*:; buildi&, it is extremely difficultto add a passiv,e system to a buildjng once. it hasiheen &signed. : ’’ . \I I’ 0 I To date;’ a&hitects,cbuilders and owner-buiklers have made l#tl,e use of the ^ inform’ation available conce.roing passive systems because “it :is ‘&o technical: cumbe’rsome and time-consu&ring.,in application. To be useful, information , mus+t lead to the ne&essary degt;afe of accur$y at yach stage of a building’s I: design. The de.gree of accuracy increases” as ‘the-design moves from the -A , ... pschematic’stagd through detailed drawings’ancl models and finally to construe ?:.‘@’ ’ : ,+tio’n documents. ‘lh the earty’stages, it vnakes no sense to perform extensive 0 ! heat, loss and gain calculations,.since the building wfll change, amany times before a design is complete. 1 I< =? < ?I > _. n -3!,: The- basic purpose of this book is to make technical information acchssi ” e to I? a.lI people. The text is written in such a way as to facilitate this. TheLari‘ous elements that’ make up a passively heated building ‘are- expJained separately -. and,ordkred in a sequence that makes them easy to apply to a building’s ’ _’ ‘Q -.. ’ design. The illustrations that accompany the text are intended to convey very. _i p : .tPchnical information in a.simple and clear format. ‘ P /= 4 sdpTiis‘book deliberately does not use pr;ofessional architectural and, ehineeringd y > * graphic symbols to represent various. mateiials and concepts, but, instead, illustrates them with a degree of r;e.aIism. The @hotographs shew, existing . en ,& ,applications ofboth entire systems as well LISspecific details., i .= ! -c ‘k . i . : : _, .* f T$ allow, for change resulting&&new experiments and observation’, the book c ‘I e t. .- .is structured’in a way-that \permits ;he..&rder to in1prov.e and ad.d information -‘Bsm&’ I . , .i IS .;1.. syster?i.“.is earned about’ passive sys~&r~s.~~Since each element *of. a passive treated separately’ in the text, ‘the. Eetetrieval of specific Pieces .of. ,* ( ,- ‘inform.ation is made easy. .b m * I ,I :” I \ 5 ,e 8 \ LL .?:,, .-.-.I.’ .-.‘. c all locations”betwer$n 28:” and 56” ,adapted to the same latitudes in ~ - e I. bJ the Sfuth,ern Hemisphere by simp.ly reversing the sea&s and reversing true \I “I-I..,,..,.~“IYwI,,*,,:,,,u ,aemuy<.,& ..... 0 ‘\; . ‘. “T . u ‘j , /- j ‘_ 2 . - - -_ -. / 1 ,,.~, ‘\f’ ‘, = I\. * \ e * ‘.r> .%.. .’5’ ,_ .*, ‘j I _--~ i,’ ._ :. I /\ Y’ Tig. l-l: Geographical, regions ;dverecj in this’book. 5 1: a e ,,, ” ‘- “&, I ~ - ’ .*’ “’ \, ” , most of ;he information you will‘need ;\* . .’ building. Its contents: are ordered~ in S ,applications to system design and I the fundamental c.oncepts of -1” ,’ It provides the foundation for * t \. k. \ ; 3 ’ -- : ..’ I’I, ,.*< \.‘_ ($ ‘. ” \ ‘2; @F “‘I ,~ \ */, _ ‘. r;‘,.L. .% :. f - . . ____-_ .i L . . ‘: m 0 r . = 7, * .- 0 .) ^ d 4. _ : l I .. . r x .,:.: .~ . . ‘I ! I r: _.. .. c &, The P&s&e; Sqlar Energy Book ; 3 Y. i I_ ‘3 . a_A., L -,. -’ L il . , --L d - n T, _I. -... e.. und<6%a~$~+he-in~n given in the following chapters. ~Chapter’ 3 -;-- -...._-D - . ’ ~ i j”. presents the various types of passive @ems. i%i&i~g&ec~ral, examples of, -a each. system are included; .along with. performance data,, to giv.e-~o~rarr----------~. a Pndication of-their applicability to a wide range of climates, and xlocations. In ‘: . I . the chapter on design patterns; chapter 4, a method for designing a passiva- . ‘, ’ :, solar hearted building is provided: The intent’here is to lead you through, a ’ process that allows you 10 choose-and size a.system suited t9 yourlparticu,lar a 7-b I -- --: -needs. Once a building and system has been designed, its performqnce can be * calculated and then adjusted, if. necessary. The graphic tools that follow in? .s .., a . 3: chapter 5 concern the sun’s position and movement across the skydome, z- . solar intensity ‘for different orientations, obstructions to solar collection i . I j . 4. “Y and. .the design of ,fixed -,ori movable sha’ding devices. And finally, ‘in bthe ‘,b.‘ ,, ;Appendices;~‘d$ta-necessary to accurately design and. calcutate a’ pa&e ’ a $,;,“’ system is +zse.nted. geforeyoubegin reading this book, ‘however, keep in j -. ; . .__ * “mind If’hat good dest’gn is the integratiliii~~f-many concerns of. which so’i’ar -*I energy is b,u,t dhe. ’ ii*. .” . ’ 0 4-l. ,). ‘;-.,,‘._._ 1 ,’ .” *’ 1”..._____ et . 8 ‘. ., :-..__ ‘iThe Form&t * t ): * , “y’ / -*, \ ., : . . ~ ’. . .. .’ * . L* * w ,j:c ,’ ., The ‘Pass&e Solar Energy Book covers a wide range of passive solar concepts : a6nd .information. In.order to understand the d&Is of a particular; passive ‘s’ys 5_-c a: tern, .it is ‘impoHant to first * the systems. To help you ‘derstand .the fundamental principles behind all 2” ~GZ fundam,Gifa~s, chapters 2 through &are , ,, *a c,.;*- Y‘ ti b ’ & :*,- I. -0 . a‘. <,,.r * w-ritten in such a way. that the sentences in_bold’type+summarjze, the text that ,, Y . b ,, ,,(.‘a ‘.. ~YIows. By themselves, these s ntences+&ten read in sequence, form a con-. ’ ,, . (. i xl,! Ir’ ,:.1 . . tjnuous text; To read the book, first read only thh_b’old type, consulting the text Yo clarify and embellish .particu.lar po.infsbfinformation. This’ will iake you only ;, A,y’G) s\* , ‘. ; \ “’ , ‘a ; .:, . * :a’ti hour or so. On’ce you :have* read the book in this {way, you can ,go baik . 1,. ;’ * -s . ,z ,‘I. ‘, ‘* and read,‘the entire text to acquir+ a full understanding of the detai.ls.4 ‘ ‘” \,., ‘: . * . .a -. . / 1 . ..- _ . _ .e ” D : .1 *. -. .--_ -.. d- :s i . . (I, 0 .{ “- . D.C * _~ I ------ L . ;I1 I : ---;,-_~~--_-~-* i: ' . iI/ -' f rogen. was ccmverted into sun loses only + The thermonudlear fusions at the core of the sun release energy in’ the form high-frequency electromagnetic rhdiati.on. The theory which Furrently is ,- i ‘a “\ ai !;-?- ,r u,‘ - f” .. . : ss_. t , d” *‘.’ . 4 . ,- : 1 . .. / ./ . * + I : I.’ L .. , ’ _.,I ,, I , ’ I ‘*. I., *, ‘L : .. __ .- _ _. - ‘1~ i. f~ *, F I The Passive Solar Energy Bbok I I 1,’’ 7 . z, F&o 11-l‘: The sun. 3 ccebted states tt-rat electromagnetic’ radiation can be represented as either a combinak, of rapi y alternating ele’ctric and magnetic fields (or waves) or r energy particles calle photons. This definitioh of radiation is difficult to under-stand and visualize, But.~t& theory behind i-t ?Itcrws usto.dexribP and predict how radiation,will hct. Radiant energy is produced at the solar core at ” temperatures estimated between 18,000,000” to 25,000,OOO” Fahrenheit UO,OOO,OOO” ,to 14,000,000” Cqlsius). The average temperature at the surface b o Of the sun is only Io,ooo”F~(~,~~Q”C). ’ D ‘, ‘\ \ ‘3 , 6 - .. * _\, . ?_. ‘\‘. + * “‘y, .._ ----Lezz:_Y ‘-‘- i. ”i I .I ._ (I 4 .,. ” P : : ‘) , Natural Processes .f * I/ r?i A/ , The energy traveling’through space is made up of radiation.in different wave: .r . ” lengths. Electromagnetic radiation’ is classified according to its wavelength- jz. ‘,a \ ., I s,a .*1 :3 . ,.* * “ _. __I \ .,-_ . 1 -- -- ‘. ;~ 1.1 ,.. .;_* . I. ‘1 1. .- ._I ,’,,’ ‘I . ,I i /1 ** I’ P. F- .-~a _- I. 5 i the- more energetic the radiation, the shorter its wavelength. Radiation is , y 3.‘3 emitteti from the surface of the sun in all ~avelengths.+fromlmg,wa~velength --+~ + T- radio,.waves to very sport X rays,and gamma rays. I --..‘. . 1, Although the sun radiates energy in many kavelengths, it radiates proportionally mdre energy in certaio wzilvelengths. ~.._.__._~~-- - r c At an average temperature of 10,OOO°F, the sun radiates most of. its ene& at ,, ,1-1..1;,.,,,.,, very hrgh ~~eq~~~c~e~,,~sho~,w~v~engths), Visible .l.i.ght ma.kes up 46% of the _, total energy emitted from ?he sun, Visible,light, or the wavelength to whi&h ‘i.‘j & the human eye is sensitive, extends from 0.35 scientists doing, detailed calculations out in /space, Ibut on the earth’s surface the variation isso*slight it has little.effect onthe solar heating of buildings. . 1 1: ----...:. - .:’ The Passive Solar Energy Book JC , i* ,! II ,_ .,.. -. .’ l .’ . 0 .g a0 ‘5% / I.- : ,-‘_;:k 1s,:b i:( 0* L’ ,a ., ’ vlsmLE’ WEcTRiJY * g Ib :.: : - , & . _. h. ‘g g :: ‘1 ‘; “:. 1 e 1 ‘:::I::..: , <.T : 1 : ., L ._ . \ r” : *’ A :. : .. . . : * -. .. .h-:-..e:.:..-* .-.,.?’ s: ’,..” . B ** a I .s 1 1,s L2 3 1 2.6 . Y *WAVEl,ENGlH OMICRONS) ,_ /’ ’ * c c Fig. Wl; Wavekngth cha;actqistics of solar radiatioi ire given for? ii - ‘- . ,J the toij; of the atmdsphere (dottedl’and at the earih,;s surfrice. .1 * ,’ . 4 4. : I . ,P II ‘.. I/ I_ i -_ /’ .s‘c:, 1 ‘Ra’diation ‘and tlk.‘Earth’s,, Akxphere ’ ‘J ? ‘; ,.-Gj < I .‘ b. .,. .I. ‘Of all thq solar radiation intercepted .by t&.‘ear+ (including the’atm&&&re), as much- as,%% of it is refl;ected.!bick into space. The ~~lect,.kf ‘energy- \. . :I 9 4 * 1 j I -i ./ / ,:” 2’ _ _ *t ‘3. : I II *, ?. * ; I) 8 B .’ 8” ‘1 -\. ‘. I’ I +.: ; I ! . ., .I .._,.-._ “. I ‘__ 4. 3 ~.... ..__._.-_.. i _ _. - _ .___..,., ‘.Y...~-. --- , -- ._... L. ” , / :. 6 * : . ’ -, -1 i1 ’D t *’ c r ,I. “$ .*, -. . /< 1. i !. . * ,? Natural Processes .I’ r. I ’ Y’, L -“from an object is,called the albecJo of the object. The GIbedo of th; earth taken as a whole is 35 10 40%. Most ,of this energy is’reflected back Cnto space fro; clotids and atmospheric dust, but some reflection bccurs at the surfa~ce of. the earth from surfaces such as water, snow and sand. ’ ._ \., ._ Part bf the remaining portion of ,sdar radiation, while passing thiough*the ‘. earth’s atmosph f re, is scattered in all directiooS as it inte‘racts~wit~--ai;.rnole 1 cuks and dust -partijcles. As a result, some’ of this’ scattered or “diffused” radiatiQn comes to eaith from all parts of .the skyd.pme.’ Scattered radiation a primarily in~the blue porfion of the visible spectrum, is re;ponsible for the blu2 c.olor of the clear sky> k?. ” : ‘_ . 6 .‘&,.&. >4 :i. ’ Fig. 11-2:. WIhat happens.to sol’ar radiation intercepted by the ’ * -. ‘earth’& atmosphere. _ 0. I&. , (‘m \ , ” \ -b 1I . II ; 9 . ’ . \ 1 ‘: _ :ido ’ p’. .., \, t 1 , ‘I. D ‘1. --- --’n _,. “a 6.7. r” -- 8 I, iv _ --.- . -. /‘ \ 6 ,_ I : -% I . * ,” i_ :I ‘ ~ ,i ‘L. I * , il ,i * h 4 L -5 The Passive Solar Energy Book . : . “. . .- . : ” - .s * i -\ .. ‘: While #&ds and dust,scatfei and reflect,Ytipproximately,a third of the incoming r .. energy, the .watet vapor, carbon diqxide and ozone in the atinosphere absorb . ” an&her IO_to ?IS%. In the upper atamosphere, ozone removes.yi,rtuaIly all the * high7Cequency ultra-violet rad$ation reaching the earth’s surface. This is . ‘. ,/a y _/’ eisential since ultra-violet radiatlori. can. cause skin burn and eye damage and , D“‘. ’ ‘0 .~ it can bq let’bal even in moderate d9ses. yater vapor and carbon dioxi”de in .th”e lower atmosphere .absorb portions of the radiation, primarily in th$ ,_ ‘. ‘,infrared band. 2 . *- ‘I . I r. Besides the composition of the atmosphere,- the most iTp&tant fa&or in , ’ determining the &ng+,, of solar rac&tion reaching the ea@‘s surface- is the :a . . .l&ngth of atmosphere jhe-radiation must pass through. Durir)g, the day when ” the sun is directly dverhead., radiation travels through the least amount-pf ” . -. J C. . .I ‘, .I _I 0” : ‘gx’.-,<~ .,’. I - ,y h ‘d -‘k .. I -‘. 8 . ’ ,’ “’ ” . I) .. *. ’ ._ \ . > . r -* ,‘ a IA, I.“I I Fig. M-3: Aiir mass dktle~mines the intensity of direct. !unlight. ,,;, 4’ ’ i ! II , ‘, io .= . . : x : I \ ._ / .., r ,_,, .,. .., ,.. .. .1 . 1 c_,’(r- - d L Ai!; .:_.._.... ‘_ 1 ,i . :-I ‘1 ‘; “‘, ‘L .____..-.1_____,.__ .... ._. __ _,A- ._-...- - ...-_ --. > -.---~ - L i ,. I I x i .. ’ ‘I *_‘_, : * / ‘~‘4 . 0 XaI, . i _. il - . i .’ Ir \1 \ \. / 8. 4 &&al, Proces_ses R ,’ L *l c i* tmosphere en route to the earth’s surface. ,As the sun’ moves Ftoser to the orizon ‘(sunset), the path of th,e- radiation through the atmo$here lengthens.. he more atmosphere or air mass that ra$ation must pass throughl;/the less its energy content will be due-to the in&eased, absorption,and scattering of the /radi&i.on. At sunset the,‘radiation content of the solar beam is sufficiently low /to enable us to glance d,irectly at t-he sun. As th.&“;!height above sea level I increases, the amount of atmosphere that solar radiation must pass through /.decreases. Therefdre, the energy coptent of sblar radiation at high altitude locations will be somewhat higher. . _ *: i’ : . ( Because of the eatih’s tilt and iotation, the, length!of atmosphere that solar - ’ radiation passes throkgh will vary with the time of day and month of the year. . ’ The path of the earth around the sun is a sl-ight ellipse, barely distinguishable I once a day on an axis that” axis,is tilted’23Vz o (exactly ! around the sun. n ... _I. 1 i \ .,-.... 2; ‘. i- -, s!2T%wm :. -1.- - i--.-- ’ __.. ^ ‘, i” FigJl-4: The earth’s tilt remains constant. ’ .I’ 1 :. * . “Y i _’ ; * 4, Y .‘,, E. * * _ :. ..9 I, li . n ‘a /^ . : ; . 11 c _' t .s "* * . . I 1 . 0 : ', \' ;f A' ,* i I , 4 ? ~. / .' ., 8, 'c 1 ~ : I ,’ . 1 y ‘\. \ 5 ~, \’ -. i \ ;‘*. e .---., 0 5? 1 The Passive Solar _ , & ‘j ’ iJ .’ <. ’ toperpendicular to t (1 HFrqisphere receiveq fewer hour: of, sunshine, pr&ils in t& Southern Hemisphere. \ \ ,I 3 \ - /d < Ii .i’ 1 i .,.*_ j i /’ , ?, r */ :/ ‘* . a. , i -I ’ Fig. H-5: ” /;, :’ ;. ’ ,,i - ., i :. the seasons. _: ~* I. _ 0 <.’ .._I L ..~. .-. ” \ __.. ‘L \ 1 .. . -. /a- *. 1 b Natural Processes ‘* I .\ I The angle the bun,% rays rqake witW a surface wili determiye how- much ehergy ’ ttiat surface receives. Since solar radiation comes to earth i,,nessentially parallel I rays, a surface that is perpend(cular to those rays will intercept the greategt amount of energy.‘As the sun’s rays mosF,away from being perpendic’ular, ’ the energy intercepted by a surface wiU decrease. t 1. y---- Perhqps the best way t.0 imagine this pi; tq think of- the parallel rays - :, -==a%<-.> of the Sun as a handful ,of pencils held with thebr points touching a *a _-- ‘c~--_Y...-._-_“!abIetop. 7hd dots made by the poin‘ts represent unifs of energy. ’ When the pencils are held perpendicular toqthe tabletop, the‘dots are ’ . ” p 2’ .’ 9 as compactly arrariged. as possible: enefgy density-: per -sqciare inch is ,;’ \ I 54, at a’maximum. As the” pencils are inclined towa&+ the”paralIel, the h 7 *’ . :. . . I J. d ‘1. dots beg;20 coyer largkr and !argQr areas: en&rgy density per+square in:*-. :‘ &easing. -2% -3 , ..’ BarbaraFrancis’ + ,,2 7, . I .. Fig. H-6; Energy density is determined by the ahgle of .incidence,. ’ . I G= -0 *Master’s.fhesis of BarbaraFrarkis; Univetsity‘of New Me&o, 1976. 4 1 ” ’ ,. 0. . 3 1 ’ -i -.g, ‘=;* * ,i3: ~,, ,; .: . ....._ ., -. II .I /.+--. ./ i 0 . Y --. . c _ . *” 0’ :0 . .. ,’ ” ” / 1, 1 -/ . i. . v. : I* .i %“ : ’. e . / -. P .. ‘1 The Passive Solar En;rgy *Book 6. ” _I’ , I i *_ ., ’ , 4‘ a However, a surface can be facing as much’as 25” away.from perpendicula; to * the sun and still intercept over ‘90% of the direct radiation. The angle that the rays of the sun make with ‘a line perpendicular to a surface (also called the angle o‘f incidence) will determine the percentage of direct sunshine I i ” z, . * intercepted by that surface. Table II-1 lists the percentage .of sunshine inter- ,_ ., cepted- by .a surface for different incident dngles. ;., . ‘. . d / : Table II-1 Pircentage of Radiation Striking a F !’ .‘,?‘i,” n * / Surface at Given Incident Angles ’ ; . ;. t 7. c a. ; . Incident Angk . Solar Intercepted . ,@legfees) (perce_ntJ. ‘2 ? . // \ s .I -.. e , ” c --. 1 \ i 5 (J. . 1oo.b ) 1 ’ ;r \ i. I 1‘i, 5 99.6 . . , , I i 10 98.5’ 1 -D ““\ 15 ‘. - 96.5 ,’ ‘I’ .c, 20 94.0 = 25. ;,90.6 1‘b . ‘1 ,’ !,30+ . ” 86.6 “= .i” - Y 1 .7 35 81.9” : . * . L9@’ L 40 76.6 P -0 ‘ . .45 ._ 70.7 . ” 50 $. 64.3 . I <,+- - I o 55 ., : 57.4 - \ -.. I . . .: 60 “-‘- sg.0 _. 65 ‘. 1 42.3 - u &’ . ‘* ’ : h ‘. 70 34.2 * .’ ’ . *>-~~~~~,~ r.,:. / !75, 25.8 *- / .2;.” ‘. /’ 80 -17.4 j / ‘. 1, “II ‘0 85 * 8.7 / D .. 90 L 0.0 ’ ., se ,a\..-- . 4 .r I. - I P / /I’ ., ,.:‘; . ANGLEa=+LEC?F~ - I, :----- .I ,. ;*I &UaJG&b=%m- . I ..5 \ I \“, L .e. 1 .~;.’ ? ‘a I.8 a_ .* 0 \c . i , . - -. I ._ e 1 .. ; ., / . ..,*, 0 i* ‘. :~, /i. ‘I ; . .: ,*/ .i.’ %. ” 5 1 J’ . .e. *i I :,: _. , I ; f 2( I .i , . c - Natural Processes , I/. ,3 r > ’ , ‘, 5 The totql amount d energy interce!pted by a s&-face &mists of not only direct radiation, but‘also diffuse and reflected &djation. The total amount of radiant energy intercepted b,y a surface is greater than that from the direct rays alone. Diffuse radiation, 0~ the energy scattered by ttie atmosphere and redirected to the earth’s surface, can be as-much as 50% of the total when the sun is, at a lo& altitude: and ltj0"/0 on a completely cloudy day, However, on ‘clear days /diffuse radiation comprises. only a small fraction of the total. The intensity of radiation reaching a surface from a reflective material. depends upon the quality of that ‘material’s surfa% finish and the angle of inci.$&-rce between the solar beam and the ,reflector. The larger the angle of incidence, the more the radiation will be ref!ected-. S - : -. ,1. ,; ‘It js important f” realize that. the collection of solar radiation is deperident on the area of -the col,lecfing surfac.es. The energy content’ of solar radiation is A fixed. by the output of the ,sun. To collect’s certainamount of energy from th’le sun, an area’ large/enough, to collect it is necessary.., This applies to all solarheaiing systems from south-facing glass in a.reside%ce to collectors”that focus __b the sun!s energy,. The area intercepting the sun’s rays’ will determine -the . :.Y- p . .’ R * maximum amount of radiant energy that cat-r be collected. ..j + 0n 1 \ , I. .<- . ‘i -,-, Reflection, Trans~tiissi’bn and,.Absorption - ;. t p, -,, , I’ : e f’. -3. ‘. .* n i’ _’ -’ - ._1 a* c o ‘a. As solar radiption strikes the surface of a material, three things can happen. .I .^ . ./” The radiation. can be reflected, transmitted and/or absorbed. _ c I” J I . s1 . .. . ,I =. ‘[l)epending on the gurface,&&re of the matdrial, reflected radiation w-ill either C * : I’ 1 be scattered (diffused) or reflected in a p‘tedictable~~‘~anne;:iRoughi~~xtured .. ’ .-_ surfaces will scatter radiatio,n,.while,surfaces such as aG’Sirrc%$ highly polished i ,aluminu.m wili reflect’ii’ght in p.red;ctdble parallel rays. For example: a masonry, . wall, because,ofthe irregularities of.‘its surface, vyill not reflect $adiafion ina I’ \ predictable ,manner. It will &attersr diffuse the radiation. in‘ all*direct-ions. In ‘-. .. . , >! ‘I ” .’- -m-contrast, a very smo,$-r z$d’highI~$olished surface will produte a predictable’ >. -,,.. - . -- _~. reflection. (!n this manner, lig&@nd other radiant energy source3 can 64 * ‘1 controlled.)‘Yhe at-&e &which the:rays strike a .refle&ng surfacgW$ill *be equal ‘1 ::* : ,’ to’the angle of tt$. reXJc%d ra‘ys, q-5 to ;put it anothec way, ‘the angle ,of SC : : 't i ., in;cidence wilLequal the. ;iijg’le of.reflect%n. 0 1 ‘._ UI’ ” 2.. iL II . * 6’ ’ * L 2.’ ‘.$ I I : -. ’ .I h&t. v& ‘per&w as color is ‘the resultof~ v&X&-radiattin in ‘certain: wave ,t 2 ‘. j lengths beitig refiected, f~om%~&rface;~ while, all the other tiavelengths. are * _ . 1- , .i* / ‘. ../I *.<‘l -’ I> i 1 ., r , -*- ,’ .. .” -. .- $3 ,.I . -*- “Y 7 ‘I y’- ” ;sr .. 15 “. - + ,i : “.. *yj ‘1 2 i :* ,a:.+A : y: . - * :. . ,. ...--..i.--. 1 ' ';"..,A, ,. ----\ -\ . a_ . *7.._ ,, .*. I* ') ,,;, .. ,,. ; _, -, -. . : 'I *.. ; .. 3 ., -\ Solar Energy Book ; . :. ; ‘. . .. , SPECULAR ,bREFLECTION ‘\ MFFljSE REFLECTKIM ..’ _. .‘:: 1 *1/; , ‘i+G -31.+ \ Fig. M-7: ‘e,Surface’fjnish de&nines the qual’ityof reflecti&-7 pi ‘/~ .a , _ . ‘. ‘> .. i _ -penetra~~&na~&~~w~~~ -either be *transmitted or . ;: ” .. . _.. .+A ,<*Lb! It ‘- *.. I 1 ._ : -, ‘L -, 0’.P & ;-.--___‘_ .* .-.._ . > ;, : ‘* - s ‘, i ‘. /, s 4:’ _” *_-1,K*1, , . ~ . T . *. s. :;, 0 I’ a :I r (I ,+a *- *L :i 1 I Natural Procisses _ _’ .$ I ”. ‘. ‘.n- k mate‘rial that tra&&its most of the visible radiatidn that Strikes it is TRANS PARENT. The direct passage of sunlight through. a material is’ best illustrated r *‘I_‘:~by.ordinasy window glass. Most of the solar. radiation passes through glass wjth’ ’ .i v&r-y little distortion. i2. During a clear ,win.ter, day, for examtile, ‘a vertical single .< pla)eglass window transmits about 85% of the solar ene&y-strikinh its surface, . ’ doutile glass about 75%. Other materials’can be equaily-t.ransmis;ive but will deflect or scatter the radiation that passes. through .it. We refer to, these materials a5 being TRANSLUCENT..’ , . ‘3 . .;a,.> , r _0 > ,- . ‘. . Fig. 11-8: Color per&p&ion. .I -I .. f - . The IPasSive Solar’ Energy Book , I,. ;. . . .. . e; ;i * , ( 140 1 0 tp c i . 3 ,5 c 1 TRANSLUCENT *,;‘. kg. 11-9: Transmission characteristics ofoilazing materials. P * t_ I *B , ~ I .. ,-. I \ Some radiation is reflected and some is ahsorb. by the glass. Reflection losses are greatly dependent onl,tt+e angle--of incidence of the radiation striking the _ . .&‘, . $1,. ,j’ Y ” -I i _. ) I .+. ’ I, .> 1 ,w’ f ‘\# P r. .’ \ .’ ‘% Nathcal Process,es \ ‘I 1, 1 4 :q ‘has a lower transmissivity. This can be seen by observing the edge of a glass, ‘h she,et; edges .which’*.appear greeri,have a high iron content. , 4\ :. , i Y ,Phpto 11-2: - Qiffusing diiect sunlight. . 1 - -i _’ - < .> , 19 Solar Energy Book .‘._..,, I .i a -v .The Passive I ’ .! 0. 4 -I I kg.?&IO: ~Tr’;lnsrniss~on.c&lines sharply at.‘t.nctdencr angles 1“ . greater i^ha‘n SO”. . L1 “.$ .’ . *.-..> . .I ’ ’ . li . ’ ,. :. I .- . . 0 .-2, : - . * -- I ,. 3 0 * i. - .; ‘; t‘ ’ + ‘./ , ;‘+ *- .-$a Solar rqdiation $bsorbed”by a .s&stdnce ii conver@ itSto iherr$ svqy’.cfr heat. Solar r8di;itibn ,absoybed by the molecules’at t,he surface ‘of a material will accelerate their movement. As the vibrational inovempnt of mdkules. i in a mateliol iryreases, tha heat conteqt of !he rrfbte?Zi.iqi&$y~. %:.i ’ . i: . d. ,- : .. + . 0 I . L .- . As hei1 i+zik’dleda to i solid “rkatekat,*ik temperature will r&k Ther~fork,‘~tem’~ . ljera~re~is4\F$ meku’re of&e intensity bf heat, which is defi(;ed In tey oFt,he . a’ . i .,! . I mgverqpnt crf’ molecules’.:. ihe, ,&ore’ rapid,this ,moyement,. the” hkghei the. - ~ ~temgg?ratu@ie.:.; ’ 9’ I * . -’ _ m’, .V’ . ,:’ L .’ . . ?I ’ I ‘ .’ _-... .-“,.fr*’ 4 - .* _ P’ . b2 ./, * ,’ . . \ .i, * ‘._. , - _,,-;--- ,-y”v- ;. :_- _ .:: I , --. ’ 4, , r b ,* 4. e ‘% ..- 3 .(’ 1 - .. a \ * ‘_ ’ i ‘B‘.-- *Characteristics’ of Heat’ -‘. , Ia‘.’ .. ,. --. . P . ‘,:‘*. -. 1 0 .’ ..!!..u I r c .. 9 . ’ Y’ & it is h&ted .by soiai radiation, a material seeks to achieve e&ilibri~um with 3 - .’ I . t “itsl&rr&mdings thrdwgh thrke basic heat W&r processes:-conductiqti, con-‘,,‘: l 0 * %&tin and radktiqn. ’ ,. I - .c .._ - ._ . L ,, 1., ., I . _ i . .E- ’ . * ., a 1 ac -. 9 ;:y.. x, .7 -, TC -.- -- -- _- -~ ~~~~- _~.. ~.- -7. -~-- 1 r ,‘.’ I .<,’ ., _ WC. 2 _’ ., ._. j .I _.. . .c; -> * ~..T. ___. “i !.” ‘, . L PL -“r --” . * ‘i;:’ ‘ibatural Prqcesses I ‘: \A ,..- . c ‘, ,. \..A ‘,_ First, as solar radiation is absorbed by a/material, the at&orbed ..\.‘... -...L ~ redistributd itself within the mateiial as ,it is’ passed or COru’p’uCTED between P : ‘“’ I mdlecu,les. Conduct$n: @‘the process ,in &ich heat ene\gy is transferred ’\ :.a , _ betweT molkcu~eswjthin a substance, orbktween two substances in physical _.__ 1 contact-,, by-dil_ectmolecular interaction. The &qmer molecules bump info and 1 \ I rjass some,of the+-vibrat&naI energy to adjacentrnolecules. The dilection of heat flow is always frot?warm.to $‘ool.‘As the’molecules at the surface’ of a I material are heated by solar radiation, they $ass this energy to cooler adjacent++ . ’ ‘L-molecules dispersing the heat through the rr&$ial- so th&dt. takes on a more --, -tt- wdh-e rate of h&t flow or the thermal co’&c@CtjVjt~ (k).of-a’ * ‘,_X-- , subst$nce is dep@ndent on the capability of its molecules’to sendh,and3receive ’ .’ .,., ‘ . heat. Forexam$$q,-metal, dill feel colder,to the touch than wood c&the ,.same . low temperatur$ This is due to the fact that metal/has a higher con?lu&ivi~ i ‘._ hnd it will absorb heattnd pass it from its surface to its .A than wood. The more heat conducted from the hand, ‘,. In general, because gases are poor conductors,’ “-:.--- ockets are usually poor conductors.‘,A goo,d example of this is ‘building ,- ‘, ‘‘.$ - * insulation.which cgnta’ins- thousandsqf tiny air poc.ket:s. :. 8 k--__- . ’ .. .:7. --L Second, H ‘hate!ial will Yransfer h,pat &&gy from its kface’to the moiecules ‘0 --- ._ : of Gmt$!_u_ig-?-.by CONVECTION. ‘f;onvection is -defined.: as 0) the “:’ ‘, . ‘. . ‘L-‘transfer of heat betweer&urface. and a moving flui’d, ‘or (2) the transfer of . ’ hea,! by: the movement of the molecules from onepo&t-in a fluid to “another. .-....I.. __ .‘.\a ! . ‘,.;l-n-canv~ctiop pro&seS, heat again always moves from warm%-c&LA&e - o : .,, ;... ., ,.I. ;cool*m’olecules’of a”?luid such.as wate-ror air come into physical contact with a I!,’ ” ,5’ l yarm surface,,sdme of the’vrbrationaf energy at the surface &f the material is. : / near The P$ssive Solar Energy Book . i .l 5:. .. \ )-’ ’ _!\ \j n\ u ,I .r , . - Fig. M-11: A downdrd’it creates uncotifortable c6nditions. I ‘$ , --. 0 I ,’ ._. 0 I. .-L.. --- _ .^~ . Ic=y-.--- -- --, -- 8J .. ’ .& - -.-. . I , ie * ,~ if th? fluid .is pumped~,or blown across-a surface, the rate of topve&e heat . tra&er will increase. AS a cool fluid comes in coittict with a warm surface, - .’ ‘t.~~f~~~.-i~~~~~S~nce~ the rate of h __ ..- ------ \ ‘eat flow fron43e surface EZFiFfid. t increkes as’ bhe temperaturb difference between t’@~ sub&nces increases, the ’ 4 ‘ faste<.:the! wcmed fluid moletiules are removed frc$i tt$.surface tnd replaced .I -‘.‘- l by cooler molecules, .qke ofaster twill be ‘the rate qf heat traiisfkr.-For example, * . . . ‘. ;I * 22 *, 1 - .~ a - Y r * .. \ . .‘\.\. ,^, l ..I ,s f \: 1 i e% ,--.-- 0> i ‘. ,‘,, ,__ ‘\ ‘1, : t .\.“.*.‘ 7, _ ..- . .~-.I --. --. r I m &l’ . c -/ 0 .I .e.* f Y’ \’ 1Ii Natural Processes C, .‘,& . 6 \ > . ”. ‘. 1‘i when ai:i.is bagwn against the surface of a’hot spoonful of liquid, it cools faster. ’ r : . The air molecules that have been warmed at the suriace of the liquid are blown away,j&d replaced by cooler ai”rimolecuIes which are,capa,ble of absorbing . + 2 more heat. This protess is.called FORCED CbNVECTlON. L: P/ w I’, i/ 1 Fig. 11-12: Cooling by faced convection. ! .* ‘I f, cl ~1 Q \ 7. , . 4% ’ And third, all materials RADIATE en ( stantly radiating therm;1 energy j-n.. II ,dlrec%ns bkcause of the continual 1 rgy all the tim:. All. m?terials are con vibrational mavement of~mole$& (r+easured as temperature) at their surface. i ‘ij c ig contrast to s‘olar radiation, which corisists of shortwave radiation emitted c .= I’, P at.very high temperatures, thermal radiation experienced as ,heat donsists of ’ ’ longwave infrared radiation emitted at a much lower temperature. ,; ! ” D ,I: , L 9: As the fice dies dowrrayd the flame an,d coal’s becorrie more@red and I give off less light an htly-less heat . . . after, awhile .the flame disappears, the coals ome dull red in a,ppearance, then a darker I red, and finally they no more? Light is no longer emitted from the war,m coals, but h,eat contiriues to b& g.jven a&. Th6 warmth ‘, I --- 1of the. coals-;is felt for- hours as ‘radiated heat or infrared radi’ation, ‘Ijut jris not s’een as light. $6 -__- . .._ _ ‘, : I . * John Mather* ’ I, * -= 4 : energy a material radiates debends on the temperature .L1 -.--; - EI i ,- !I P The output’ of thermal radiation from a surface not only varies Gth surface tekperature,.bAt also with the quality or EMkSlVTTY of the surface. In general, z .+ *John R.Pjather, Climatology: Funda6JentaisandzA&lications. i . ‘23 ’ ” 3 , >, 0 ,j ! ‘.,: e i IT , >:. , ., ‘. I ., ,.:-. 1’ _l--i.-..-- .-.-_----, - -. ~- 7- < F-J=--““‘- I 4... ,..~ 1.. , ‘b -J ] ; jJ!-”‘Lip .._“_ ” -” ! / ,* f L -1 , ’ 1: ,c 1 . .Q b / P I l .” , ,/J’ ft$“PasSiv~: Solar Cn&gy Book -L.. ._ - D. . ._~__.._____--...-----.- I~ .__ -.- ..-.. --- .‘-.~--., ,__ n _ I P. 5 .* . ‘.’ ., 4 . . --\ most materials are good emitters of “thermal radiation”, that is, they radiate. _ ’ . thermal energy easil). -‘ihe emitGnce.(E) pf a material is afi’indicator of that . ‘material’s abilit~,~~ give off thermal.‘radiation. Mos,t building ,ma@rials,. fgr - ‘,I example, haye erm’issivities of 0.9 which means that they radiate? 90% of thei thkrmal. energy theoretically possible at a givbn temperatclie:’ Norma’lly, highly ,.: ;,polished-surfaces, slach as shiny,metals, are’poor emitte‘rs of t ,‘mal;,r8diation. T *b- This me&s they radiate very Iittl,e,heat at a given te&perature: \ I ,,o I . “_ P I \,,; 3 - NoI all materials,-howekr~~ -bbsO’r& tbermai radiition; “some w~ill jreflect it .. reflect thermal, radiation will the surjace rather th’ n on jts i_s a good indic,$ion of the ability uo P ref ect solar :! the ability to reflect the-rmal radiat!o,n. Mdst t 01 color, act as a “black bc@y,” * 4bsorbihg p B - .I >L- n n 3I _I, 1.111 i e *- \. t ,r ,I .i 1; ‘general, &&‘higl$ p&shed oi shiny Sirfaces, such as, altimqpuk foil, * reflect large amoknts of .ahe thermal iadiatiqn t-hey intercept. The/ designers of .air@~n& tak6 advantage bf this principle bj/ provid,ihg the unqersides of : airplarjes with, a polished metal finish: so tha,t ihermal -energy or heat ‘radiated _. ..! 1 _ Jrsrn ti hot.asph$t rqnway will be,refl@ted, this keeping the interjors of th: pldnestCcoqler w,hen phrked at a terminal. - ,, 3 . ... I b.> / ” . ., _0,,..4. ‘ .IThe’ amount bf thermal radiatibn/A shriace intercepts depends on th% angle the radi&ion mak& with that surfi&. This. is- the-same $priiicib e that. applies to ‘1 0 ; ..I . polar r,adiation. Two surfaces that lare+ar&lel ts and facing each’ other will . _~ i .‘-- ... --’:c--..-----exchZije. a maximum Gnouht of theC?iKGdradiation, while suriaces facing each , .. t: \ 5, er.at an angle wil-I exchangc”lesG If both. bddies have the Same‘atjsorptivity, ” e result of this ener& excharige is a’net radiant heat trahsfer frpni the warm :,, .\I. body td the- cpql ,body.. .,-- --: * ,$“,S “’ . I O. r 8. I;‘. ? , .- - -2 .__-~ -. ‘I 6 5 -- I : \\ . , :y \‘, * ‘A.\ \ soi‘ i t’ _‘_a ’ .(. .Materials that transmit visible ~-~&i&err-do GX&c&sarily transmit c* -. is c thermal-radiation. .,-A- .-’ I--- i< 0 .h . D ..- . \ ‘< .5 * Glass, which allows virtually all the visibl pak’through, will absorb most of the I ¶ rddiation it. intercepts. This collecting &lar ‘Gnergy,~.,.Qnce - -_- ” -1 . !*In physics, aXTkKbo~&is an ideal material that ,; . _ = ‘- :24 . ~ ,., ” :.. --.-.._,__,:_.-_:,._... .*~_1;. .--. _.,_.___. .. .- -I:l----& ..-. .._ .,__ .; _, _: . perfectly. @ ,; ’ :. I . ... . --5 , . ,/ ‘* .>’ ” ‘, ! r i SC ./r a / . , .i’ I . ” v 0’6. . Natural Processes * n; k e absorbed by matejials in a space, thermal energy reradiated by these mat.erials will noI pass back ourt through the glass.’ ’ i ! This process of trapping heat is c’ommonly known as the “greenhouse effect.” A good example of the resl‘llt of this etiect IS the heat that bbilds ilp in an ;lutomobile that has been sitting in the sun for a few hours. Other materials, s,uch as some plastic glazing materials that adniit a high percentage of solar radiation, will allow as much as 4O%*oi the thermal rhcliation they intercept to pass through. In this-aspect, these maderials are slj,$?tly tess desir‘able for . :‘- ./ -’ usp in solar heatin,g. 3 L : 7, 7 .s / :.\, b c . ;\\ .w e 1 :: \ i‘ c F’ ‘4 . I i. , Fig. 11-13: Greenhouse effect.. ,(;“’ [. .-:. , ,,‘F - ~ -.” .; Heat Storage ‘* ” ’ - ’ n , All solar-heating systems .hre based on storing solar energy within. a tiiaterial for ‘a period of tinie. This is accomp1ishe.d by hea4ng a material which will store the tieat until it is need?d. Coojing systems; on the other hand, do exactly the opposite. A substance ,is coole.d, or heat is taken out, and kept *This does nbt imply that radiation loss.esfro& ‘2 space a‘re eliminated. Although glassdoes iot tr_aq,Smtithermal: radiation, it absorbs this energy and then reradiates and conducts it to the / 7 [ outside, but at the tower temperature of the glasssurfa&. ’ /’ I. ’ ‘.. I 25 L . “. s ‘Z __ I’._ .-T ,” - ““:‘. .’ I. .. I /. I. i,! .,/ * 3; ;t , “‘Z) i’ a I .I t ,. -/ . . , I .I ’ . I’ ’ ’ I’. -_ Ij I,. ‘. ., .-,. 3:s; j . i’ ,’ -.. , ?he Passiv: Soliir Enet@ B6ok ’ ,; .i’ p _ ,:, I - - : ) I /P rn .” . ,,. , . ./ r _,&- * thatwayso it cai‘absorb he& at adater titie, Heating and cooling a space is +entially..based OF the same cancept. Very simply, the i$ea is to keqp a 1 q ‘1.’ ” ( “te?‘%perature difference between the substance and the surrounding tempe’ra tu re. 0. .. . ‘. ‘9 a. * ‘Eqr this reason, when solar heating a building, it is impoja building of a substance that can store enough sol& energy (2 to con+?!. the heat) ic the day-<; d p .t P ?, 1time t+ ke.ep& building &arm during a Cold winter night. The capaci,ty of a .-’ .,/ matCat to 9tare thkrmal energy is &lled=its specific heat, which is defined as L c l A’ i the amwn[ Of heaf (measured in Btu’S) &-te pound of a substance ca‘n hold 1 ’ 1 when its temperature‘ is%raised one degree Fahrenheit. In the construction j.’”. ’ &trades, however, the-quantity of a su,bstance’is t’requently given in cubic’ feet . : &-‘*, a i’.’ ’ rather than potiiids. ‘The&fore, the volemetric heat:capa@ty of orie Cubic foot , \ of,a substan& is simply its -specific heat multiplied by its density (number’of /, peunds per cubic’foot). * I.. ,\ I .i I/< I :., -; *i \ Table lb-2 lists boih the specific heat and heat ca’pacities of various substances. 0 :. .-, .: ,. I\ldtice” thy! alth.ough brick’and conctete‘ have’~+oughly half the Specific heat’ of expanded ,polyurethane, their .. ,., they can store substtintially sity is much greater, so per unit .volumg L . ?’ _ ’ .\ r i .? a- \ l . 1 : ‘? ,_ _ : _ .:r. o 3 . . ., .;. ,. ; _. : ‘b ) ) \ Table II&$\ Specific Heat ‘a!! Heat Capacity of Vari’ous Substances, ’ ‘y’ # :- I > _\, s : 0 . t ,: \, -:: Substance ,, Density Hbat Capacity .’ D t _, (lb&u ft) (Btuku ft-“F) ” .\ G ,1 0 --_ , ,) . ,, .“’ .’ ‘II, 5 144. .: / &0? . ” ;>. -. 489 39 _ .’ 1 y-A”,.- . \ , -*,,,I)..’ F”\ 8, ,- ‘.X,, ‘j:’ ‘,‘Ih_/ 4.:2I ‘i,+‘. .; ..i $g-;:.:.. a; ,_. ..Y/ ,-,. . ,) ‘) .’ ’ .. - ;. i - ‘+ I’ ~ : D ’ ,I’,,(,i -* : II .%y..,,/- .n $‘i ?I I,‘,,‘,,;,i &j\;,:,.:;:; .;.,.:;z:::..;..y:.:’ ,,, .: ,I’ f “. _, -‘: . .:. .I.’ -‘n_ ._I 1 i *. *:- I P ‘---.. --.. ,,,, ““// --55.... .f cc.... CC””‘‘-- ..:: .’ r. ‘-. c--:,i _...l~. I* ., ., ,, ; / ‘. :_ ^ ,I ),, :::: ,, ‘,,‘<, : ,,..II * * -3 0 :/’ ,p, -3 >_I, : .,. : ‘\ . .. * .I * , _,,* * hY v .* “J , ;.. . - -. ; -- II,, )) ,,‘‘ii’’ .’ c , 0 :;/ “’ ., * f ,‘i __LL ‘. I - 1 ~~““11 ..,,,,’’ ‘, D . HHqqwweevveerr,,.. aappaa$$ffrrooTT hhaavviinnii ““aa hhiigghh hheeaatt ccggppaacciittyy,,.to.to be effective,_as a & t : ,,.2 . ‘storage medium a $&stance must ,&o have a relatively t ‘storage medium a high .conduc&j~. (._ Y“’ 1 ., :’ ..” WWooGGdd aanndd.. bbrriicckk..hhaavv$$&&oo;;tt tthhee ssaammee hheeaatt ssttoorraaggee ccaappaacciittyy;; however, wood”is’ ‘/“. t uussuuaa!!ll,,yy nnoott uusseedd ff&&rr hheeaatt ssttoorraaggee.. TThhee rreeaassoorrrriiss ssiimmppllyy tthhaatt wwoooodd ddooeess nnoott ‘. f’ .a ccoonndduucctt hheeaatt ,,aa$$ wweellll aass bbrriicckk aanndd.. iiss,, tthheerreeffoorree,, ?ot capdhle of .transferring’ ssqqffaacckk ttoo iittss’’iiGGtteerrii,,oorr ffoorr ssttoorraaggee.. ”” / . . ,.* iI 7, ;/ . T’ l c D’ ;,j,.- . .. I ,. ‘II ‘,l q 2 .. ,,1. *a,I y ,;,/ .’ ,-f+- I ,~ . ’ , 1 i”. ;: %. ,,:. , . . ‘i , I’ .,s ; r . /,, ;,. / I .* , ,_ .-: ,’ /’ -1 11 i.,c v /, I. ” -.. .- , ,, . ,, ,’ ;’ ” h I 2. .a ,_, ,k -I .+ .-A,*., ” .i .., ‘-! :, . .‘. 1: i; . . . * ,c\l - i-i’ . ,. I .< -.* \ 1. ,:~., I‘-’,. \,, .5 ._ I,‘o G 3. ;‘:;f / * \‘2,” 1 .._. ,’ -\ ‘. i” ,,.’ ‘. ’ a.- . r) R . ‘,F i r" 40 '. .. 't -. I 4. B. ‘. . . .. AA ‘Y - : .. - . I0 .. ._ 271 ’ -; Passive SdzW Systems. i _ Approadjes to Solar hating _ / _’ i /I. i. ,,/I . \ (:,, ‘, I; There ark basically two distinct approaches to the solar heating of buildings: ‘% LI active and passive. a / .;p.. ,/ ‘! ~I . * .. ‘In &neral,.active systems employ hardware and mechanical equipment to -- n “collect atid transport heat. Flat plate or focusing cdliectors (usually mountedion 1 the roof of a buil,ding) and a separate heat storage unit (rock bin, w.aier,.tank or , _:(‘* co’mbination of the two) are often the majo‘r.elements ofpthe system. Water OT .“ .1 air, pumped through the coHector, absorbs heat and transports it to the storage unit. This heat is then supblied from the storage unit to the spaces in a bujlding ’ , ” ’ by a completely mechanical distribu’tion system. 1, F , Passive systems, on theother hand, collect and transport heat by nonmechan‘, . * i&l means. The most,common definition of a ‘passive solar-heating and coolisng . system is that.it is a system in which the thermal energy flows in the system are 7 by natural means, such as radiation, conduction and natural convection.. In 17 . essence, the building structure orsome element of it is the system. There are . no separate collectors, storage units or mechanical elements. The most striking ‘difference between the systems is that the passive system operates on the r energy av%ilable in its immediate environment and the active system imports -e--- - -: energy, such ‘as electricity, to pow-t&-&s and pumps which make the’ . 2 system work: Q -, ‘. c G 1 F There are twb basjc elements in every passive solar-heating system,: south “.; facing glass (or transparent plastic) for solar collection, and. therma! mass ‘for _’ * I .3 .d I ’ & 42% ,; h i? ; ) ! ,* &.*I. A 0/ . “*., .. 1,. i .J ,-. c s, Passive Solar Systems ? heat ab&rptioq, storage and Odistributi?d. Popular belief ‘has it that iiassive i, . ..-ovI.T-”e... _. ~. _-, _. building. must iriC6’Lpora’te large quanlX& ‘?if?hYG? two elem”Gif~~.‘~‘-6r~~studies ” -1 ’ ;how, hotiever, that while there must be some thermal mass and glazing in ’ n . ,?.-., _’ : each space,‘when prope”ily designed they are not necessirily excessive. This will become evident Gh&Y you read the sizcing procedures given in chapter, 4, ‘.(pes,ign Patterns.” ’ _ a ’ I. To establish a framework for understanding passive systems, three concepts ’ will be “defined: DIRECT CA\N, INDIRECT GAIN and ISOLATED GAIN. Each explaini th& relationship between the su?, heat storage and living space. Within each of these categoric? we are able to identify various systems, ’ ._ . birect. Gain _ _ : , The firsi and simples’t approach to passive solar heatirig is th@ conc”ept bf Direct Gain. Simply defin.ed, the actual living space isdifectty Heated by sunlight. When the space is used as a solar collector, it must also cqntain a method for absorbing and.‘.storing enough daytime, he’at for cold *winter nights. In other words, with the direct gain approach *the space be&mes a live-bn’ solar dollector, heat storage and distribution system all in one. One important note, Direct Gain Systems are’always working. This means they collect and use every bit of energy that passes through the glazing-direct or diffuse. @sj Because of this, th& not’only wart well in sunpy climates, but also in Floudy climates with great ,amourjts of d&use solar &nergy, ti,here active .systems can hardly pqrform as effectively. ._-._ - -: - In this approach, there is an expanse of south-facing glass and enough. thermal mass, strategically located in a space, for beat absorption and storage. Southfacing glass (the,coIIec,,tor) is exposed to the m&in& amount of solar energy i! winter, and minimum amount in summer. For this reason; it is the Pdeal location for a’dmitting direct sunlight into-a ,pace: ‘Since a portion of this solar heat gain (sunlight) must be stored in the s$ace for, use at night (and pos$bly during periods of cloudy weather), .tRe floor and/or wal.ls must be. cpnstructed of materials capable @fstoring heat. 1 -. t’ ~ 7. Today; the tw6 most.common materials used for heat storageTare masonry and ’ water. Masonry theimal storige materials cnclude concrete, currdrete block, brick, stone .,and adobe, either individually or in various combinations. Typicallyg~at least one-half to two-thirds of:the-total surface area in a space is construFt@d of thick-masonry. This imb!je$, that the interior be IargeLy cdn 3. “4 s- ” i ,’ 0 29 u ., 1 i2 df e,xposed mass the other hand, ~A,, ’ ’ door-and sp$ce tempe,t+t;res begin to .drop, this-heat’ is returned to the space. . u ” _ 0 (/ .i : I' i., 0 $1, I i '. : :* Ia ‘, i&rs%tl~~ one wall of a space. Thelwater wall- is located in’ ‘< . the Space in such a way that direct sunlight strjkes jt‘for most of the day. ‘~ M&terial$.commo$y used to construct- thg. wall are plastic,.or metal containers. R During the daytim:e, the mass is charged with heat so that at night when out- . .D . ‘. 0 n 3 ,, a u : 1 *c ,$ 1D Fig. Ii!-1 : direct gain.sy&riv. a , ~^ D :. n .. ’ .I 0. b -we\ 0 ‘, -- .. .c1 ; . ‘30. .. D’*., f;J ~ ’ ‘-i\o ~ ; I \ 1, ‘* ’ .- ’ ; 1’ . 8 F’ ‘. 1’ I :‘. E . . II - , ) 9 ,,, : ’ ‘. : -- ” , ’ ,_’ I/ - , : ’ ., I.t*,.’ I _. _ ..;....,....... -.___I _ ?/ _~.. ~~~-~-_~ _~~ __ . , r $9 ;,_/I__’ a : : 6 ;/: /’ a .\ *<. Passive. Solar Systikis \ v* *<. -jl e ; . ,: ‘ .+ -1. II . .‘< I’ Y ‘\,..” ‘~‘l~n’ho~ summer climates’with’cool nighttime t&nperatures,*the mass ‘can also B; .. ,’ f . act’ to keep a building @cool :during the day. First, because of its time-lag&a ‘?l* properties, massive walls keep heat from reaching..the interior of the building 0 ‘.’ _ , -.- until the evening when outdooretemeeratures are cooler. Second; outdoor air ‘ , .I ‘7 circulated, through tlie buildingTat night cools the interior mass so it absorbs c heat and provides cool i.n,terior-surfaces du$ing the da.y. I *\ ’ . e ‘,9!1,P%. 3 “PI <0 * e 1~: I one-of the earlikst and largest contemporary examples of a Direct Gain System n is thI! St. Qorg.e’.sXounty Secondary School in Wallasey, England, near Liver.*Ap~ol. The building, d.esigned by-architect Emslie ‘2 Morgan, was completed in ‘I . ;P.,, 1962. .Public reaction to the building at that time was that the architect flad somehow harnessed. a new physical principle. It was not until the late 1960s that extensive research and testing of the building was begun. @ \’ .- p ,. <\ . ‘1, 0 1 - . x“Xj The -build$tg, constructed ‘of masonry, hasEla transparent qouth wall for 4 = ’ m@mum solar.gain in winter.’ Concrete, 7 to 10 inches in thi’ckness, forms the /I = roof and floors, with the’,north walj and’ interior partitions u-?ade of %in.ch br;jck. Th;s masonryis the principal means of heat storage in the building.,..lt is ,I’ , “, exposed to the0 interior and insulapd frqm theV+terior with 5 inches of / 1, , expanded polystyrene:.QBy contrast, the eni~rk south wal! of the building is ,_ esserrtially transpayent. Tti sheets of gfass, the outside layer Clear ,ahd the insid,:e translucent, make. up the roughly 230-by-27-foot wall. The translucent _layer’refracts~d(rect sunlight diffusing it over the surface area of interior mass, somewbat..uniformly. ,‘r c> - 0 $y . i L.. ..“; . m . ‘The ~masok$ krior stoie$. heit and acts to p&venk large fluctuations j,of itidoor temperatures over the day. Becorded classroom flu)ctuations are on I* the average Gnly 7’“F throughout the year (cl&r-day ftuctuations are ;omewt+at ;\;, ’ higtier). Thticlearly illdstrates the effect masonry has in keeping indoor tem ’ peratures rel$tively stable. 0 b c m %; ,~ 81 .c- : :1.’.:.....l;i,~.’ .: : The south wall ‘&nits enou& S .building’s heating needs during rgytosupply, roughly 5O?b hf he .i-- : . \ ?.e ., * climate. Wallasey is located on, ‘the wes r; kd all this i? a less-than-ideal . f England at 53”NL. Its outdoor o - ‘r& temperatures are moderated by the f Stream, but the current also ’ * i’ )..“-i := .’ , .brings,with it much fog and cloudy weather. te; at best thought to be . ‘, .. ’ “/ ” ,I ‘margina~l&suited;for solar energy application, .Bk\ -the sun with the remaining 50% supplled ‘by lig utlding is heated’5d% by students. The conven- ‘i b.. . (\ .. \ tional heatjng system, originally installed, was Fever and su bsequentjy @ ‘, removed. . B .c 0. ;,>.8,,I_: &’ ‘< -2. ,. ” jai \ e a .\ 0 y! _. 9 ..’ . _L, _ 1. \_“‘.. - : *‘- x ‘31 . 1- t .: 0 ”0 D . ?, 1 .n ‘. L) . . J < .J.-. 0 _..‘. -i .. t.: ,,,_,, ‘.’ . ;, ,_ .. .: ,, i’ 0 ‘.( f - 1 -. .a. / The! Passive Solar Energy Book e ‘_ ; D _ * . 1” “--hL’E Table *!ll-1 principal Heai Sources a t’* 1 Percentage of Heating Supplied c_I B----- _I_____,.._-~~j--v.- LE.--,-i ,-___ cGiIijjh esttmateT-‘- _~_._ -. -_ e 4$. . Sburce (196&69) m ., I’ .! Soiir energy - 1 50 - ,’ Incandescent lights , 34 cl l.JOO‘i~n classroom ’ I 2,400 in art .rooin + S&dents: 15 tq‘35”students ” 16 ‘r< . 0 ! per c!ass L SOURCE: ]osebh E. Perry, Jr., <‘The Wallasey Schbol,” Passive Solar Heating a.nd Coo[ing Con *, ference a‘nd Workshop Proqedings (Springfield, Va.: National Technical Inf rrnation c: .’ ’ Service, 1976). o s6I ‘. ’ \!‘r u * I) “is mq‘ k il. a L ’ ‘9 ; .I a ‘\ _ .r fJ” bflck wall faded with pfartor, - 5” tnrulation t ” .!... ,,, ,‘1~ j !*l 0 [I . 0---- ~.“_-- ..; 2 ._!’ . i1 63’; I -i ,Q .. .. ,i-.‘.Q‘ Fig. 111-2: Sunlight ii’diff+ed over a large.i&ace area of mason&. 0 .’ ‘S ..’I ; -+ 1”. _:,,, r 32 ,_ : y s ‘.., j ” - ,I,,” ‘, :.’ _. .. <_ ) ; . 9 L --,- -. -_ !_ ,‘P., ,: ?’ .- ” ^.w .- _’ .’ . ..e ,. ‘,’ .,, .- ‘8 ‘-.. “’ -. . . < : ..._ :. ;..4_., * , i -passive Solar S&ems ._ Photo III-I: South and north face of St. George’s County Secondary School. . I . -i ” =. .._,,, .~ 1 10 J 9 1 e i 0 .’ . -, 1 1 3- * ) .i.. a ,-. ___ --. - 5: ..i . 3 ,‘.. _ -. ” , .0 _d Y .. )I i .K\\e . , ..: , .Aeassiv.e* Ej&gamk-~.- .I 6 R ~1 -- ,. - ,’ c ’ -* Another, very different applicafion of a direct gain concept-.is Maxamillian’s ’ , . restaurant, located in. Albuqyerque, New Mexico. The restaurant employs al ~._____.~~__-....._...._131i~~c~~Gain~~em-~o.suppI.ya-m~~por.t~ion of...i,ts-wioterheating-creeds-anda--’ .- _a.. . . --_ ..(“” natural cooling system to me:t its surhmgr cboting loads. I 4 I 2 .* 0 “\. ” , *^ I -1 I- 1. 1-L . .” , ~--*f a 3 6 9.12-3 6 9 P 3 6 9 Q 2 3 9 .Q h 6 9, Pi?-,6 0 Q , -- --+I. / I-, =I ~___- .; htDOORN ~~qg&Jfp~&j#j&& 7, -._-. i. ,.a.. NOVEMEjER 25; 26,27,.1977~ . e ’ ^- . ‘. D . , 6 (’ i’ r . sc .-~ Fig.,lll-3: paxam/llian’s restaurant (here and fddng page): j I : ;f ..’..I 34 “-, -~. .-. ., . - . _ ,., , .I .B .- ., _” “; ., %.t/ . ._ . , i,‘. b I,), ‘: . , : ’ :_ ,O .., ,... ,. . . . , .. I”-. ‘c ( ( ,, d $ ,, 8,; 1 :, ‘4 i. -... .b . . .,li^- ../ _. m-. -. ~. . . . I - ( *uMrirC& .- . ~? I -- I SU: N c : . ,. . ,. 1 I 1 . . / .--i ! .; I 4. *,*,-; B I rL .i ‘4 SUMMER ANC&i%i OPERATION’ ’ c (I . . ~, . / -. Passive Solar Systems 6i r L1 3\ , ~NSLOUWCIEN~G) g!@gQ” . i-._- . * to evenly and effectively absorb and store the incidem energy during the daytime Bi * . “_. -. “-, d. auxiliary heating , at night when the : being warmer than a conventi in .a radiant .heated space, is “felt” as i I nally heated space at that same temperature. To ’ avofd the possibility of,overheating in winteP, the.clerestories were slightly undersized to allow%r’the heat gains frpm lights, pe,ople and appliances. ;r - <’ Y ,,?. ., . ------:--..I .~. --~ - -- ...-_.- _._._\ . _, __ _: r i _. .~. ,__ lr-c - . ‘=,,. -7 3r : o ‘d b’ + (_. P. ., . . ‘. , e = ~’ ‘. / ~ s :: / ‘3 ( I’ ./ i- ? = - j. I d .? I. * 8 . .= : .I -. * ” The Passive S*olar Energy, Book L? c +L . .4 -. c * 2~. .-3 .4 ,. _I__~_ .’ ” .,....,.,.,.,. t ’: I -> *Photo 111-2: Interior.of Maxamillian’s restaurant (here a;dI’facing page). ., 3,fj .; . , _ ;\ @ b i \-Y!l/i _‘ ?, _,”I“-14 1 .. \\\’ , ~ ‘j, \ “; A * ‘, .>xy ” I, _* k I’ ‘. $2 c. \ Passive Solar, Sy’Stems . -_ .’ ‘T ’ ’ ‘,/ ‘, j> _......._ .p--- . ‘* .t In-so-&m&, cboli& is accomplished by ,ket$ing the sun out and by ventilating 5’ a the space gt night. Most often, nighttime temperatures in Albuquerque drop into the IOW 60’s: By opening both,windows on t&e main level and the vents e po*sitioned high in the clerestories, 2 convection &irent is ind’ucek; cool air is drawn in’through the low openings and warmed air rises out thcough the hrgh ‘. vents. The masqnry in the-space, cooled throughqtit the evening, by this . 11 , 1 c * 1 ’ . I ” * ’ “, .* a’I t. i a : _ 1 i 3 4 - 1 37’ ’ , ,Y’ .*- , .\ i , * 1,’ I . / i ..P \ 0’ \’ e ’ . 0 f. ‘ I. . ),” , .I :, I .._. _. ,i .---: I .' p 'I) 1‘ _D , :a * ’ The Passivd Solar Energy Book , . , ,: ,\ ’ .I r , m * .?’ ..‘. I * / : natural flow of +jr, absorbs h,,&t and provides cool: interior surfaces throughout ,&----z.----..-e,*’ , the ci - .-” ,,. _--- * I . ay,> -A&o, when ou@Zir temperatuces;ana..j.~~ti~~-~re most rrifFiiSe , shading devices p$rtiit~only’indirect tight to filter into the,restaurant. h‘r ~,-,,-:.,*._-C~A**.l.-*-. Duringjbe++$-+f of 1976-77 the restatiraqt qp&!ed .‘%-..+a,~.%., ,w...B*.A.A.l.l. ..,...,....a.-.*...L comfortably ‘with the ___._. s?ln (and people) as itsonly heating source. -.-.-Io.a.I “‘.>..f” .,.a_. . . . . ~.,:. i- ,. * .IoI ’ . D’ * L2 ..r +d yet anotgei example; ‘the S‘chiff residence in western. Wyoming, demon; stcates $h&t~ iassive solar -.heating can work effectively in very cold norttiern * 4 l . climdt&T$e residence design.ed by Marc Schiff and Robert Janik ~8s corn~- -. pl&?d$%PZ. t’t is sjmilzir to the pievious example i.n:(hat it has a south-facin’g, $awtoDth ti[\erestory that admits direct sunlight’into the. building. However, ; :\, .-. . ‘1 ” ^ _ I c 9. .,. ; ‘, ‘. i‘, I i.. * 1. , , -10 “r ,I .-? ~ 0. i i,,> Ii.1 1 I1 I I1 I I I I I I I I I.1 1-I I I . 12 k 6’ 0 $2 - 3 2 2 ; 12 3 i.nl: I r..p 12t3 ’ AM. ‘-, 0, ? 12 3 0 9 12’a.a 0 1 b’ . I A.M. PY I AM.’ .I P.M. u ‘/ ,’ I - G,T NOV.9 0’1 ,I’ ,” yovALj * ’ .’ , . NOV.40” .I .: , ,‘, I’.. .- _I a, ,.. : ~ s i. . . ..,,, :.. ,PERF&@ANiE ihi NY);EM,BiR ft9p .. . ’ ,.;;, f, ’ / .I ’% F 0 1 / ‘2 . ,p y,-.+ , . . I. -.,e c -7 ,. a b/ I Ip 0, Pikive Solar Systems Ll R 3‘. * . r ’ ’ ‘. ‘1’ SECTIPN Q:yI.*K :,’ :;:,>’ ’ . ..:; _” t ’ “;,a;a..~. I . :.,,’ .;.._ lmnlalun’~O * b’ , ,. I i 18,’ 6;.‘,,(.7,;‘, .:’ L*c?7.., ,F’ Li’ r ‘1, ’ ._ ,’ PlqN Fig. 1114: * .I * $zhiff residbde (here and facing pa@. Y / Ib , I. 6 0 ’ ;s:- : i ‘39 \ ,/ . . .‘. . _ I Y ‘.. 0 ‘, - >‘. i;. !iL ‘eo;’ ,< -, _, I .., ‘I ,* r’,. 1 The Passive Solar kn, :gy Book ii I- c - _ PI I’ i , ^, : mas.s for heat storage 1s con~~~~nccl 11;1COII( rcatcl hlc)( L. \\A\ tIIlr~(l \t,t(t> ( one rtlt(x and flnishecl \Gith pipster, and scntl,lllX,, thls Dlrryt (I,lln SL~ivn1 IU~C rIon\ in th(> ~rll(’ way as the ~allssey School ~&fit1 ,\~~.~~~n~~ll~;in’~ rvqtCjurClnt ,” Figure III-4 illustrates that even during periods of 0 F weather t,he buildipg maintained temperatures which were 56 F above outdoor tcmpeA$ures. It I\ I inmesting to note’ that there 15 no hta,lttn$ \\stcam 1r7 Ilit\ ~.cs~d~~fic~~ oltjclr thdn ctwo wood-burning stoves, one in thca II\~I~s ‘I)~cc’ d’ncl oni’ ~fi tlitl ni,l>tvr t)(>(l2’ room. The owner >tates that “ahe house feels \‘cr)’ comtnrtablc clokvn to ahou~ -,,,62”F a?? temperature and tolerable to about 5.5 F due t”c~the fact that the \v*aIJq and floor are from 3’ to IO F \\,irmer In the evcnlng tl>Jn--the,alr ttamper>ture _. ? _’ i .~ . ’, i 0 I ,I > ”: +k!x+~_.,:-.- r , + ,, ., 1. \ :, i/. : 1 *. . “” ,? , .$d \ . ‘, 1 ‘.) > ) ., i b ,I 0 ^t .. Y’ P I” $ /,I , a .:’ ‘i. 1 / \ /;, .’ :: I*’ 9 i i ‘a : A 1 o.‘a L ,’ ./ I C1 f ,I * .’ I .” L Passive Solar Systems . .. L’ 4.” _1 -’ Photo M-3: The Schiff residenccsouth-facing Clerestories admit 0 * direct sunlight; YJerior (facingpage) and interior (here). 1 1: . .m 3. I s 41 c ,. c 4) .. * > . - ‘Ln 0 ---i-J-- .,..4+ ’1 1 i, ”1 -i 1 \ Y .A b , ~:ms, ,. ‘: -. , <~ ._ I -_ b *. .I The ,Passive\$dlar Energy Bdok Many applications of interior water walls employ a combination of materials. For example, the Karen,Terry house in Santa Fe, New Mexicq, is a Direct Gain System with both inter:& masonry and wat.er walls. The house, eloggated dong the north-south axis, follows the contour of the south-sloping terrain. Tl-ie interior, separated into three IevCls by ietalnlng ~~11s containing ivatrr, IS constructed mainly of brick, adoh: and concrctc block. Th consist of Twenty-eight 55-gallon drums filled with water and ‘p retdlnlng wall5 ~rl’,lnti(-orroslvc 1 additive, and covered with mud plaster. Sunlight enters the space’ through ,t south-facing clerestories tilted at a 45 @ angle from horizontal. These Aerestories are plated in such a way that sunlight, at mldday rn lvlnter, strikes the water walls for maximum heat absorption . *0 1.. ‘,’ ‘L’ . I L ” 1 i ” ,~, , * 6-r. (_.L.,.,. _ ,.; . I‘ 1 - P i I _. I_ .. > - .a Phato Ill-& The Karen Terry house-terraced to the south for *, maximuni winter solar gain. 5 ,( !’ 1 r ‘I \ 8 ‘, L, \> Indir& Gain\ ., _:\ ’;,,” 3 -- i, f 9 0 i* i i”-5 Another approach to .pa’$ve solar, heating. is the cb&Bpt of Indirect Gain, ’ h b --+-St . ,where sunlight- first strike a thermal mass whic.h is located between the sun ’ c 9 ’ I3 ,pnd the space. The t absorbed by the mass is conv’efled to thermal I, )( % < ------>I ---- -.w’ - ,, 4 aI Lr. 10 P “L _! ~_...__ _..- ~. _.i .._. -. i_. “.__“~. A---. Passive ‘Sblar Systems . Fig. $5: Section, Karkn Terry house, Santa Fc, New MCXICO i: * , In the winier of I’b75-76, the auxiliary heating supply for this hwse consisted, of one-half &ord o(,wood, burned ih a small adobe iireplace. Wi-tt/lout applying insulating “‘shutters $ver thP dazing ,at night, the house t$aintai’~ed tempera b tures in.YqZnz +&&high 60s for most-of+& wirliel. w+aest recdided t&mpel;iIure in the hbuse that winter, was 53”F.early onq morn’ing. ‘ II between tFie two systems 4s the location of ,.“1 being heated. ‘I, \ I. i -I, \ i *1, . _I ‘, ~ I .) , ii < _ :; I ., \ Y @ * a 43 _ I ) - \I~“’ ^a II 4 ‘ ‘P : > ‘? ’ ” ‘I .i. . : a) - -. ‘0 . .. i .B \ i). i \ I ,. ‘6 -~ e - D .’ . ‘lh’i ‘Pass@ Solar En&$y B&k ‘Y ‘? n i I.‘< I,: ~’ us. - * I _) .d’ .Y 4 , : ----.. j- --. e*x The reg&em&ts -fir 2.: Thermal Storage ~lT~~S-$tGK% ‘&&&kg glass %Feas! (or: tranq@ent plastic>- for-maximum wint{r solar gain and a thermal , 1 + mass, lodated 4 inches ,or ho& directly behind (then glass; which s’erves for, heat storage’anh. distribrition. _ z -2:: .I’.’ _ 0 ‘. 90 II s. ““There +‘g^wide range of appropriate thertial stordge walC~aterials; however; ’ ’ ._ * , I,. mo& fall into atwo categories: 7 .-? ,iither maspnry oi water. Masonrq materials . ,?.,- . . i, ifi.c!!‘ude’corqerete, concre!ti block U(solid o,rfllled), brrck, s,tone and ‘adobe.’ . ’ Coptai~er.s++..(or “wat(r idclucje 1metal, Ijlasjic and’ cbncrge with a -waterprbol ‘b lining. ’ ’ -. -, “s, ,A 4- ” :‘.Ib‘ . ‘1Masotiry 1 ,c.. /‘ I ” .’ .. b 1 .: -tl . ” (. ,A m?so$y ..wa _I I 6. ; ,: ferring &i&he sunlight O,J-Iits oute,r face and Ihen &aqti 9 ndktion. The outsidebsuriace ot;. the’ a. ^ . wall is usually pajn,t or’rhc bc5& ~~ossibl~al,T-;or~~~~~n Or .‘_. , . .’ of sunlight. Heh t. cb L- s then distril3.utcd 10, ll?r sphcr , .by radiation, and to n,‘-fTom~the inner fact. . * I .a. ’ ? I! 111,. .’ By adding yeants +o the wa$ i-h.; di,stribution’o _‘> : r :;.,:, (thermoe.ircula-tion) from the extirio;\fqce-of the 4. ‘, ‘0 ..:., dicring the daitime;rnd.qarly eve+ng’Solar radidtion ‘1‘ .‘.i . . “.. . I . p_I’ . $.,:’ b hhii..’’ , ! x )1 * 3 .I ” jl I Q&Y--, ____ PG‘’s _ “’ _’ , :’ . ,. j MIGHT -;s 1 ;’ . L._’ : \ 1F,i.g. W-6: lndi$ gate+ tiasonry themal stoi&e wall. ? *. .-‘I b ,. / 1 . - ,:.. ... ..& I” ; ‘.*,. ‘_ . . .‘,“*, i. .D*f .* s .0-s.. ,:~ .,.*1. .,44, a 1 u * I :?i ‘* “ID 0 * n * l *’ ; 1, ~~~;,;; . I ,_.~ I 4 “0) ‘. -. .I .> .,, . . ,. _ , b -“. : ’ 7 :.’ #* ” . .L ;-. 8 ,T, : !;,,’ 6 ,. F& , \- 8. ” ” _ u 2.. * . . ,’ __-_ .\;,,.: rT <“ ,./ . ! D*‘.,. ’ _ l t - ._. -1 . ;‘. 1. , _. .QI .1 r A ., . L_ I” : : ~._ “- Passive Solar Systems 0 TV .r c”yy~“.‘~w,”..,,.“,i,l..‘“.,.,+ >v*eitjng Its surface to temperatures as high as 150”F.C 0,. : , ’ This ‘beat is 3 -I 0 2 i- . 1 ,a \t A well-known itxample of this systUeQmis the Trambe house Od.eillo, France. The hous&, built in 1967, was designed by Fe’iix Trornbc an$*a.rch’iiect, ]a.cqucs Michel. Phe double-glazed thermal watl i.s..cor?‘structed of codcrete, apprdximately 2 feet thick, and painTed black to absorb the--sunlight that pas&es thro;gh the glass. The hou”se is heated primacily by radiation and canveitibb fromfhe inside face of the wall. on “53 . . .Re,sulis from stbdies shoi that appt’oximately 70% of this building’s yearly heating, needs are supblied by solar energy. .Rcscarch’“un(lcr.taken since 1974 indicates [hat ,Ibs~t 36% of ‘the energy ir;lciiclcnt on the glass I\ *piiccliw in heating the building int winter. In this spn&, thci systtlfii’s ctiiiclc~nq I\ co&~parable to a good active solar heating sys\cm. WELL-ItiQULATEb ROOF I , , ” ‘. . . ‘. . , .” .’ .-. : t. iI’ JLr 0 l:. :. , . .’ . L a . I# .D 1 c_ Fig.^ll117: Section, Trombe house, Oieillo, France. II s2 * 7 ~ : i> 45 ‘C 8 _‘, I ‘j’ , -_ r the low vents in thYwall. In this%ayjcjclitional heat Can be supplied- to a @cc &* . ? : : 0 :!? -. d ‘2 D ” f ,$. 4 ? tP .G I Passive Solar Systems ’ ‘L Y’ 1b a 9 \ I 3” 0 . .? F* .! e -1, ,‘B . 5 n .+ “.. i 6 . . - 1 ,. ‘_ _. 1, ‘, The Passive Solar En,eFw Book ~” o ) o o . ’4 . .‘\, % a .a ,(,“’ r \I j_ I_ locatjon cjears the ihadows from trees in winter and alsd.provides for a large s i r .single south-facing o&door space, r8 / T i 1;. -’ 0 . 1; .-. L *.-L The solar collection system con&s of a IS-inch concrete wall, paidted black, ---- I e i --~~t~--t~&h~gt~ oJ d ou e-s rength’ windoiv glass placed in front‘of the wall. ,,I t ., :‘.. - Heating is ‘mainly accomplished by radiation and convection from theOinside ’ :.. ,,,...... . ..,a; face of the wall. H,owever, vents located at the top ‘and bottokn of the wkll ‘. 1 on each floor p&-n-tit daytime heating by the natural convection of warmed I .= air from-the front face. , a b ‘A PE AC&ding to data gathered i; th&Ginter of 197s7$ ihis passive jystem : 3-%edu&dspac@ he&g costs by 76%. Most often,‘tegnperature fluctuations in. I .. J * the house during-this period were small, o.n ‘the 6;de.r. of 2” to.6”F. Down- ’ stairy the seasonal high and low teinperatuves were 68” and 58”F, with the _..: i avkdage about’63”F, atid upstArs.72” and 62”F, with an-estimated average of - * ** ” ; _’ 6;I”q. The up.stairs experienced”*slightly higher temperatures die to the A- migqatidh of warmed air through the open stairwell cotinecting the levels; :.L 1 . T-,’ . 4 ; SeGqtiaJ mogifications, such as the, addition of operable datipers to pr,event ~ Q reve se ther’mocirc.ulation at-night and a door at the top of ttie open stairwell f o -‘.i .. to r duce .heat migration tb the second #loor, wkie- madedbetween 1976 and . J9P . This ‘improved t!e system’s.pe’rforl;nance so that the solar contribution o . d. ,:.. %$wai.greater that year, feducing heatingcosts by 84%. I L 4Water Tk~mal~ Stoiage Wall ,9 - .e .’ : ’’ ‘,~ ., , .‘: (“,,.,1I...,>y....I...I..I....ll...”..,..‘., ,........~<,...~...... j...“...-- - _ \’ ,I o. * - , ” Essentjally masonry.and water thernGl St&rage wills collect ;tnd distiibutq’ heat 0 ’ . . to’.a space in the-same way only a ,w&r .tiall transfers this heat’ through the’ .w&by convection rather t ‘an by cgqluction. The exte’rior face of,a’wdter a ,I ur;ual!y painted,b!a_kl.~r .a &&&&Jor-for maxiniu.m s&G absMption. ’ = .- ---.-- -. As thk wall absorbs sunlight;its stirfaqk temperature rises; however, ednvec , tioq..curren~..-wi-thi~~~~- r,~ti=T&yz’” ~’-~ jC t -$ . ’ tribu’titig the collected he& throughout the entire volume of water (see pdttern -- ‘. 12 iti :jhe next chaptei fpi a .comple& description of this process). Thi”s heat .is ibert supplied to the sbace mainly by ;adiation (and some convecti&) from ‘the interior faqe okthe’tiall. ‘I, . -~ ’ ’ .’ 4 L- iL----f$~. -- i , ,- ‘s I .: *’ : r The clas$c~ ex&ple ;oof‘the Water, Wall. System is the St&z Baer residence i’ti * ;ColYrales,“$Je\?i Mexiio;-T)eXhouse *‘s a series of ten so.nnected. doies which. i 1 enclose 2,000 jquare fe’et,.,&, floor area. The domes actually employ a co’m- . j .,’ ‘. ‘I ._.-.-. .w/ .-....,., _ s ., .- - .~. BI 3. ’ *Passive+ Solar Systems I’ . , .I, =@a * L c MY’ -’ NIGHT \a ; ,e c Fi*i III-91 ‘.Indir;ct gainJqwater tberinal storage wall. * . I I *I .. /’ ” ~_ * -L ; < ‘j 1 q . ,: )_‘, , 33 I* u biiatidn, of passive beating systebs-dirgect gain Bnd ft,hermdl‘ $t&ge ~+tlls. f’ * ,ii Some of the south-facing walls are vertical and contain water-filled 5%gallon , metal drums, stacked horizontally in a metal support frame.--The. walls ’ 440 square feet in area, are single-glazed and fitted with eiteri alf S These panels: a,re hinged t.o the wall at th$ bottom SO .“that b their “open &&ition, they fu’?($pn.a!, reflectors, incre.asing ‘i through tde sguth wall. ‘Atgnight, hoisted into a-vertical wall, they insulate l&e wa’ll*~o keep the heat cdlec&d by. :. space. control ove;‘the heat output of&e system’has been : +lL,q , Ccriains ar*e drawn over the: inside face of “the wall when L ~ i1 _, ” )I’ - ..?-d___ .I _ .:, f I This system kee& temperatuies inside the b&lding ,. I betwe’& 63” and 7OPF throughoht most of the winter. The water wall, tog her w$h‘- in@hor adob;! concr$c floor, moderates. th’e daily fl tuatiomYLof temperaturs uilding.VFluctuations tire small,,on the P rder of S 53 _’ f -.- L ‘.. . ,I .f J ” *” r a ‘, , d / ,. ,’ .- :+* ,: c , , I The Passiye Sol,ar Energy Book e __. * , _ 7 . .J ,. x? q 183D-IA’,Y ,w 5 .; ~:i , j j, t1 “,i ‘n,‘. \ ‘> Fig.‘W-10: Indirect gain-attkhed greenhouse. n3 I i\L .a . 8’ I - ” 54 e _s % \ ‘_ ,. 3. . ^ . , ,I , : Ii i .--_ I Passive Solar Systems 1 7” . r * d Photo Ill-8:, Attached greenhdqse to the south, ‘I 1 t P -,-, c In a Roof Pond System, the’thermal masj: is locaied on the r&of of the building. In this case water ponds, enslpsed i; thin plastic bags, are supported by a ’ roof (usually a metal deck) that,also serves as the ceiling of the room below. The system is equally suited to both heating tn winter and cooling in sum’mer. I * 0 i ,, /. I’ si \j \ .J 43 55 ‘F - “. -. ., ., : .I. ., ,.i, * * e I, , p _ , zz+:*--. ~-‘- -7’ YE .-- ,,n_-m qml 1‘,; _: , , 3: -( “’ ;i’, I” .. ’ .” ‘-* -.a , ?’ ~ _ yd I 0 ’ L-2 I 1’ ‘16: .. Sola; Energy Book l .. -. -, I ,* .,. I >- I f I \L ,’ ’ I. I In w&&r, the po~~qls are exposed’to &nlight during the day and then-covered with insulating”paiiels at night.:-!$eqt collected by the ponds is’mostly radiited t I from-the ceiling directly tojhe’ppace below. The con;ection of h’eat from thP _ .ceili.ng to iir i&he sp%ce pla’isa relatively mi& role. ” . ’: -.’ 0 Ir&umme~t~e pa?el;posiiions are reversed, icovering the ponds d.uiing the da)’ ’ !G protect them from the sun and heat ind removing thev at night to allow Ahe ponds. to bee-cooled by n;lturdl~ con+vection and by radiation to the ~901. night sky. After being cooled at night, the ponds ar% then read9 to absorb heat . c’ ;: ftorn the space belbw the following day. * .b ,based on Hay’s desigri, was built. The. residence, pesigned by architects John Edmisten hnd Kenneth-Haggard, is located in ah area that has both heatihg a&d coolin$ requirements. ‘P . . 6 i ;. 0 A ’ ,. ‘,1 ; .‘. ._ ,’ .- . ‘, c + ’ . . : ’ .: e d , i1 _~ _ * : c.:; >, :.$ .: /’ (I 1 I Pqssive Sdar Systems * P . .” 4*- .,I _ 1. . ” a e .* j i t 9 . ,P _. iiI/!T;/II j;!j i , NffiH-i. .,’ 1, I ‘I . ... ,;-,o ’ y -_ 1, .; 4. Fig. 111-11:~ hdirect’gain--kqot pond. k :. \ “.., 1’ ~ ’ ” ,.,...&r.“l-rrc-.l n 1 > 8 7 .e , 22. - . I ’ Sh . . . ,.& ,B’ .\ n,~,,-L, 1I, *\.” 1. * The Passi,ve Solar Eneigy’. liJmk ~ I. q , ’ ’ /‘“.I a, : ^’ I ’ ‘q \” 1 oL ‘& ,. I\;* f,&,L :-- I^ ,I _*-&,~+T--‘T-*-.--“-‘. I, t* \ I I.1 ,,I I., It, I,, 1’ 2. 1 L . 10 11 12 a; 4 9 6 7 1 0 10 11 )12 yoowI( ‘> ‘I, ‘... HOUR OF d&f .. -v r i .I .i x. - :a ._ : ,b. _I \ b. ‘.. ; 11 I1 II! I1 I ! ;r,,. I. ,, ’ 1 1 i. .+ F 0 . ’ & j * , P&ive Solqr Systems .. Photo 111-9: Atasqadero residence-first residential p;otot;pe ,‘( ipcorporating a roof pond Lystem.. . * aI v. ( A third app!oach to passive solar heating is the c&cept of Isolated Gain. 1 ~ In principle, solar c4lection and thermal storage are isolated from the living . spaces. This relationship a,llows the system to ftiction independefitly of the . , !“y building, with h&at drawn from,the system, only when needed. bthe natural cpnveciive loop,., ,.>T L 0 Th,e major cbmponeIi!s o? this system include a flat plaie colkctor and &eat ” + ., 7 \ \ -k - cr.-.. e Lb ‘i 1 . i m: r i 24: \ * ;,’’ ,-. \ :. I :. ‘. The Passive Solar Energy ‘Bodk \ 5. i i stor&$ tank. Ttio ty&es of h6at iransder and storage mediums are used: w!at&,r 3 .and air with rock storag-e.& the water or Air in a colle’ctor is heated by Isun 1)’’ s tight, it rises and enters tile ;op of the storage tank, while simultanedusly. ” I c pul,ling cdoleF’water or air from-the bottom~.of the t,ank into the coll&ktor. -This natural convection current’continues as long as the sun is shining. ‘... i _’ ?‘” .,. \ I ,‘. . ’ . .R ” l&rhaps,the simp,lest,use of the convective loop is the thermosiphbnivg\ h8t 1 water heater. Alth6ugh there a* many variatsns of this system.“.moit/ are ! , - 1 chtiiacterjzed by a flat plate colleqtorconnected to a well-ins:ula.ted water tank 1 by’ irqulation-wrapped pi,ping. The tank is dways located above~the’ colleFtor . ’ i to i&uce a convective. flow of fluid, 1 1 ’\ i 1, .,’ 0 s ~, .- I e. II ‘\ .’ . 1c ~~ 1. -Z’ HEAT j ‘; .. : *i S$fRAGE I F; Fig. 1~11-13: Convective loop. &J<. . D : \I . / - __ ----- --_‘m- -_c -3 ‘\ __--_. ..~ 0 . 4 i1 I. i ’ i \ rl D P .-. ‘* II ‘I I -. ul Davis The earliest example using.arp Air loop Rock Storage System is the P /y ,;;-J house in Co.rral&, New Mexico. Air lieated in a 320&quare-j?oot’coite ” tor rises 10%the tpp of a-rock bin located directly beneath the front porch of t i!‘e house. 0’ As warrin air-comes ip contact with’the*rocks, it cools and faHs to the qotto’ti of I - v .’ ...s \, ..-z ,..-.- I . - ,.__- - ‘1 I, / ;* \, ......z.......__64 ..-Iac”* I __. . ._-_. 1 - .. . i I .Ii- -_, _-.._-,_l._-.. . ICI’ i 9 : F, . i ; _j I : . , ’ ” _ “, I I .D iI , ? > n . -.. . Y-e /4 -. , cI 4 Passive Solar Systems4 c : * I ‘” ..-..-._..._-._-.-____._ 7-*T D: ; .‘t, B -+---- I: -- -J-L , c -2 ‘. ,,< ( . ‘J u cn Photo Ill-lo: Paul Davis house-to actommbdate the natural heat . .^ _----. c ~- disrrib~tio~-s~~~~~ve~~-, cdtfectors and rock storage bin. a P)’ ” 1. .: .+ s 1 / ‘ . 1 ; I ~~.:~:L -. e * -. m ’ 4” _ _>. . r ‘. it;, ; : ‘3 I”_.. ,_ ,.. . -%...+“h” . , The Passive Sola; Energy Book - . a 0 0 1\ d0 e La * .. 2. the bin where it ig returned to the collector by a duct. At night, warm air is n t supplied convectively t? the ho&e from the top of the bin while cooler air 1 isObeing drawn, from the house to the bottom of the bin. : . \ !’ a ^ ‘1 -= -m.$p ..’ , ‘u Th&conve’qAive loop is-,q&ntialJy a Flat PIAte Collect& Sytiftm. The methods ’ used to d&ign and ‘size these ‘systems are similar to thos@..used formve ’ P-&stet&-Ihe cerwetie-loop .will not be discussed further since’ it is outside - the scope of ,this book. / -1\ .- --,’ ” l .p .1 i 0 ‘% ; ), - i ‘iz., . 8 , , . V”T,T1 I ‘!,: .>a . SMH~y claims havd be& mz&de for ihe $dvantages of pa$sive solar heating -systems. These claims’ cprr be separate’d. into three categories: f econ’bmic, “. “..._ architectiiral,and covfart/health. It is Prnportant to realize that the extent to e’ : which an.y of these claims is Galized depends on the-extent*0 which the actual * .‘dksign is successful in ach-ieving i,ts_goals. 1 1. - - -,: ----A : r- r ,‘$ I . Y *’ a * . Of great integst to’&&e iAvolv4ir-i pasGves)istems is th4. possibi’lity that the ( .’ .sys’tem not only affords large savings .of energy fdr heating, blrt that it ‘also can . -. ’ ,.. _---- be inclu$ed at little or no addi&nal cost in the original design and’ constnr-‘--- . ,, _7-- ,- e-2,’ -tiog sf ‘a b~ilc&jj. Sihce- the pirice of ‘m aterials.varies greatly fro‘m &ace to pIa& i:t is not ‘possible to generhTize about\ this claiin. In iome situatibns, such ‘. 1 ”” \ h as a masonry building, it is p&Ale -& incl&Wa Direct .Gain Syste& at nb _ extra c&t. In qthqs:?aG$ wh~~maso~ fi. ... , the.ektra cost may be considerable. The s/ghifiicant econotiic advantages of-i, ,-I A . _\ ’ system&an only be:evaluated in.terms of +Ipartijcular installation. , 1. : 1.. J .t ., j . .or gril?s’to@eal with. -o-ra&a-tot-s’, connectors ; !1 $ 0 * i&j D \ r 8 . .-.. .@ 2 4 w __.__--. r Y ‘. *_* ,3 Phdto 111-11: Bus’shelte;--simplicity of design operation and f 4 maintenance; north and south v ihv s. .P ‘ e .-___~ __ . . ‘i 1 ,% “S >’,i s I 1 I \. .) ‘63 , ._ . i? ,/’ - - ,., _* S’( ‘i ;-.-.I .’ . . * , ,:.-. __-_ %--The questkm of comfort‘depen~&prima& cm-the miintenance of a$ermal 2. I ri ll..-’ 0--‘m-‘-environment i~9’,wliich .&e ,bodv lose beat at a:kte equal to its production i :--. ._.._:,,. without the need twsweat on ,$ ’ _--I__- ._--. t*’ ne h&l (w fhi\;‘er bn the other. The a&rage 9a ...“..UP.-URI-._,.~..-,-.~U~~~~ltat rest must cpntihpally &ork to maintgih’ circulatjdit,respiraCtin and Y ~.&W&..ftinctiong. .Th& energy needed to’carry ot+#hese functidns’ is ‘I ‘7x- . ag$pximately 80 Btu’s per hour: Sncethe h&&n body is-$sse?tially a heat _. engit$e with a thermal efficiepcy of about 20%, it Vmust dissipate 460 ~~tti’s~~@r~ ., ..m --.-:- hou: of-waste heat to%s sur.roundings. I .~ _I , , d . j1’,, “. f ’ Th.e body. dissipates this heat by .three ‘mechanisms: evaporation, convection - 1 and ra@i6tion. For sta$&rd conditions, an adult at rest with light clothing in ,, . 74”J %ir teyperature and 50% relative’ humidity .has Anrevaporation of 1 7 pers’pir’ation fro’in the skin of approximately 25% of the tpt;?l body heat ,loss or, 100 Btu/hr. The loss of heat by convkction to the surrounding air constitutes ‘bI. . anot-her 25% oral00 Btu/hi, The remai’ning 50% or 200 Btu/hr is by radiation I .‘PI ” . t’o surrounding objects (walls, floor ah.d furniture). G 4 0 .’ ,. Ia . * rs 1 1 :. Frodthesd figures it ,is possible tystalqlish a relatlo$ship between, the average temperature of all ttie surrounding$urfaces or mean radiant t’emperatute (mit) I, ..I .’ . $.. _ : al. ptj#cfy&qZ~~~*:~-~t ’ 15 &QJfqq(+&+& a ,c$p/o~ I.~- ’ , :: . &-eater effect or;l. body heat loss than a one degree change in air temperature. ’ .I. ,;..I‘ ‘s Ot’, for thk .sa&7e f4.eling of cowfort (?O”F), for each ‘I “F increas.e in’ mrt the e. “.. * 4 . i a> space iir temperature can ge Table Ill-2 giv”e_st& yaltes of mrt ( ‘, *. ’ ‘and the corresponding air.tem ‘” Notice t.hat a mrt o’f 15°F to produce a feeling of 70°F. 8’~~m ‘{, (’ ‘I 1 I’ 63°F will producq the spme “l”---r--m---;---“” .,I,. fe&ling,of comfort as’s 70°F mrt atid 70°F air temperature, ?.__y- ,’ _. 1 .I e .‘! 1. * 0: *\. i-. t I..” +../’ / J ti ’ !‘. + .,, .J r-J - . I f ‘:+ .‘b- q i. .I.-- 0‘0 i - - b 1,‘s. \ ‘b. Mean Radiant and Air Temperatures *“,/. ,. -_(mL ~ 7’. (., ‘_ p Feeling of.7O”F ‘.! > \.>,.I . : ..’ “,, $y> . e, . I IW I I I. I I I I !. , --- * i * ‘. ” ‘.F ’ ‘i .,.“: -__--~ t-_. ; ..’ . 9 Q I I . (‘.. I e i, ) ( h ..I f‘- ” 9 , -a 4 Tassive SOfdr. Systems 3 a This makes it difficu-lt to state con~lus~vety, In terms of hard facts, rhat t~ertaln interior conditions are more comfortJb.Ie than others. 2 Within their omfort range, most people kill dccept the statemint that the lower the ai P temperature in a space, the greater the sensation of comfort and health. Many people feet coo-ter a~i is ntore invlgo:atIfig, iresher and less- stuiiy, and tha.t [heir ability to work (and think incrcClsc$ 1r1 a spaccl whercx they ‘Ire warm but,t”ne’air temperature is tower than 71)“F! - rl As has been previously noted, the iriside air temperature for comfort in a passively heated ‘space is usually somewhat lower, and frequently substantially lower, than in a space heated by, conventional (convective) means. B. Another relatively intangible advantage of passive solar heating is the main: taining of a warmer floor. In cold ctimCItcs, convcclior~-l\/J:,o healing systems e, can lead lo unusually large itoor-to-ceiling temt)cralure p,r;l$icnls, with IOLV : floor temperature5 causirig thermal disConi(ort. In d pa5I;ivcty tbc~L\tNl floor I’; usunIty found 10 be higher ‘.’ _ _ ...._._than....a ,similar floor in a space with a convccrive hcaLlng sys~cru,.regardlrigs .<“-/ of whether the systen,\ is ;1 direct gain, thcr.niJt storage ~vatt o’r ~.ooi pond. -i 1 By contrast, the, maior problem associated~ with passive systems is one of * ’ 1 control. Since each system has a large heat storage capacity Lvhich is an integral part of the building’s structure., its ability to respond quickly to changes is ’ greatly impeded. Also, storing heat -requi.res a’ change in the temperature of a 0 matGriat, and sinke >torage n-iateriats are an Integral part 0i the living space, the space wilt atsd fluctuate in Lcmperature. ExcessivP gpacc Icmperaturc flvcluations can lead 1~; unsati‘siaclory comiort concti\lons II’,J~C! system js not L properly dIesigned. . I Fortunately, however, there? are relatively simple solutions to these problems. s For residential applications, temperature control i;cludes operable .wihdows, shading devices and a back-up heating system. In large-&ale applications, fhe , .solution to control lies in cmhoosing a back-up system that can respond effectively tb the users’ comfort requirements. There&ill always be, fluctuations of i I indoor temperature but these ,,can be minimized by pro-petty >izing and to’cating fhermal mass in a spice. -. - -- ; 4 il. 2, I’ 1 . -\ ‘1 ..._. b. : * . . 1’ . 1 : P, II , f . .. . ** ( l’i * 65 q. a; I ’Di 1 I .. D _, 5 1 ,a: ,I ,A*” . ‘k c .. I ,1 i J , ”. All adts of.building,,tio matter how large or small, are based on ruks ,of themb. -Architects, contractors, mechanical engineers wld.-owner-builders design and .build ,bui’ldin’gs based on the rules of thumb they have dev&opGd through ’ ’ years of their own or-other people’s experiences. For example, a rulerof thumb a ’ to determine 6e depth of 2-in& root joists .is given as half the span of the ioists(feet) in inches; in other wor&. to span a 20-foot space one ,would need roughly 2-by-lO-?nch joists. Calculations are used to verify and modify these rules of thumb after the building has been designed. I_ 1. .‘I We call these rules of thumb “pattelns,“’ Each pattern tells us how to perform and combine specific’.a’cts of building. We perceive these patterns in our mind. * They are the accumulation of our experiehces about the design and constructionof b’uildings. The qua!:ity of a building, whether it w.ocks well or not, will depend largely upon the+atterns we use to create it. ’ ~, I9 I’ To be useful in a design process, rules of thumb must be specific, yet not overly. restrictive. For examplhif you are required to know the heat loss of .a . ” space hefore applying a rule\of thumb. to size south-facing glass areas, then ,the * - 0 rule of thtimlj’ is too specifiP9nd of little use since a building ,has not yet been * defined. If, on &e.other hand, therule of thumb recommends an approximate size of glass needed for each square foot of building floor a\r%a,then the glass -/ o . *~I I -----carr-be-~ncorp~~?ted.,~nto the-buildingls de&n. After cornpletIng a preli-binary : \^I‘) 2 ‘\\ * design, spaceJeat (asses can be calculated and. the glazing areas adjusted ‘- ! “~“I, accordingly. ,;‘; i 4 ,. r----- . 0 > ’ * T:.- Design Patterns . . t \” , -------- i, ‘. .a Tp’ ,~I i” ., --.. . Fi e\ . : This ch&ur co$ains twenty-seven patterns for the application of passive solar ‘4 .. energy systems to building, desjgn. ,The patterns are ordered in a rough, r’ *’ r;;;.. “, Pm ‘! ‘. ,_ r 9 ‘. $ . ‘+L” . . ,i’ . ; .Jl i,.?.*;, ;, _. *I ,* ,.’ ,,a . sequence, from large-scale concerns -BUILDING LOCATION(l), BUILD.I~G :. *.’ b . SHAPE AN~~~T)RIENTATlO~N(2)-to smaller ones-MOVABLE INSULATION . (23), REFLECTORS (24):fro.m applications with the most influence on a build- ‘-\ .-: .:L-,w_ m --‘ing’s design to”on.es which de&with specific details of the heating system. . e-- -‘- When-us.ed in this sequence, the patterns form?‘a step-,by-step process for the .‘_I ’ -~-design of a passive solar heated bui1din.g. Each pa@etn contains a rule of ’ .,>* r thumb,, based :on-all the available information at this. time-for that particular ’ --d&t ofthe b,u.ih%‘ng’s des,ign. ._ ” ., : c, . P. * . Each ‘pa’ttern is connected -to other pattems which relate. to it. Eve’ry.“pattern “. ’ , -is~.i.ndependent,iyet it needs other patterns to help make it more complete. I Larg&scale p$&erns set the context for th”e ones that follow, and each succeedI i.ng’ pattern lielps;refine the one that came befo’re it. For example, a .window *I * will be more. effective as a solar. energy collector if the pattern, MOVABLE . .:I,1’ r _‘* F I,NSULATIONf23), which r’ecommenbs using’ insulating shutters over windows, at nigh$‘is used wit,h the pattern, SOLAR WINDOWS(9)I’ ‘0 r iat’ (Is #Lb - \z’ 3 . * N : . ‘, ” p .: * h’ ,*Each pat)tern has the same format. First, most \i . Y or .a vi&$ ./epIesentation of the pattern.) Second, , d -i , para&aph which relates the pattern to the larger I f& _ \. Yr for it. Then there is a statement of the problem. -After the problem statement ‘is t.he recommendation+he solution to the problem+-w~hIch gives a specific ! .s> . j c : rule of thumb which can be applied ‘to the bui,lding’s design. Also included in . , “2 .-._.. . ( most recommendations is. a diagram describing the rule of thumb. Then, the ~ 1‘&.. p$te.rn Js >cross-referenced, to .the smaller. patterns that relate to it and help “’ aI, m$kd it more. cornpIe& And”finally; there. is theb information, which contain% p all the avail;abfe .data about the pattern and evidence for its validity. , CL. 0 i ‘I’$ . * I. .. . + Together tbe‘ p$tf(erns for& a coherent .pieture k?f .a step-by=step ‘process for . ’ is written in such * ’ read the information in each tpattern when a more ’ .j_ ‘.> ._I ” / \ The patterns can also,be used to. analyze or critique etisting buildings or pro- ” iI 1.; .’ *.\; “,. posed desigrrs:“It is poss’i~ble#o~look at a building spattem by pattern and.see .*;a : *. f ‘. P : d I A 0 ~ \ .I.. 1 1;L .I ‘I, -1 ’ )I., , ” *. , ‘: \ D ,/...- ;;. ,, i ., I’,: \.” ,: I , . ‘a ~2’. ” \’ ..--+ ,_.._ l-.-_--.,__ __,, 1‘. .,_ I’. : + ____ -“‘ --_-. _ s ; r $ 7: . :. \ \! .’ ‘, i) -,’ r>4, I.-, 1’ Ti i .’ ( ,, 1 r., ! \ ,t ,-\ ,, * ,; I ‘1 I ‘.-I.&,. -- ‘, .-‘. _’ ; ‘_ ” ” _ 1 .. \ 4 . 0 8.S f /’ B * ._ Heading-descrjption of ,the content of the pattern I/ a’ Photograph-kctual implemen tation of the pattern; _- ..- 0 Related ‘Larger Scale Patterns---’ patterns &hich ,help set the context for this pattern 7 *. Piobleni Statement--dm$i bes I e of the problem 1’ , The Recdmmendatiow--3. rule $f thumb that gives the physical relatidnships necessary’ ih‘ solve the Ff’roblem . /---- . .‘I I. , ,’ . -. Illustration-a visual repres,:ntation of the rule of thumb .’ u.0 Rekafed Snfaller Scale PAtterns--patterns which ‘embellish this-pattern, help implement it . * i 9. Solar Windows \ ‘. 9. S&r. Wihdow + Fig. IV-I: Structure of a pattern. * : .. ap,ply to Bach project.’ For example, ‘the -% Lb.:,* j i (7), giv/ei cri / i 16. GREENHOUSE CONNECTION’ ^ ,--.i P ‘.?. . .; *. *. Roof Pond Systems’ c I p1 3 .i 17. SIZINC(THE ROOF POND. ; : , 8’ \ _ c 18. ROOF POND ~~EJAILS . i I. = , , w 0: - -- ._ .. ,: Greenhouse !, m ,.: .I ..* ! lg., SOUTH&NC Gf(qENHOUSIE 20. CREENHOkjSE ‘DETAILSLI \ : , ‘$5 21. COMBIN,N&?YSTEMS i 4 a i- 22. CLPUDY DAY“$TOR+GE / * i f, , ‘i., ..- . J ‘%. And thi&l are the patterns” with &ec,ifi~ instructions to make the building more 0 efficient as a passive system:_ _ !. 0’ B 1’ I. 23. MOVABLE lN$.ULATION’ 5; y* 14. REFLECTORS I 9, . 0. I(. L ‘.. 25. SHADING DEVJCES 5 a”, . 26. INSULATlbN ON THE OLTSIDE.. t 37. SUMMER+CO~~JNG -I’ I . . * 8’ -i ./ Remember that these pa’tietis are e&lving and ,will change over time. Each ’ 6attern represents a current’ recommendation of how to solve a particular a. >’ defined, new patterns will be may evolve over time as ~ , 51 I,. * .. . D -: i i This n)e@, that the patterns should not be taken too literally. Since>resear&, _ y -- ---- ‘a I into passive * i I . .’ 6‘ .* ’ 4.’ ,/ ._ 3’ L /I’ ~ IT“ 9/’ , ‘, . _’ :* .~ I i i.1 ‘. ‘.i _i .P* ,: .> : ’. . .” 1 (A - . ,. “’ i / ; 3 I , c , \ \ ’ \/I _ . r ‘G, I! The apo,unt of:arc taken.In placrng Clt)ur’ltllng on J SI~C\vi;h respccl 10 open space and sun is perhaps the 5inglv na0s.t Important (ICilSIon you \v~ll n7;1kta almtlt ,Jhc building. D . r ‘/ Buildings blockedv froE exposure to the+ low winter sun bettveen the hours of c1) !... I i;. 'I :9:00 a.m. and 3:OO p.m: cannot make dir’ect use of the sun3 energy for heating. -’ During Lhc wipler months, appirosrnist~~l~ ~10°~, oi :hc sun’s cnclrgy output occurs hctwrcn ‘tliv Ilnurs oi 9.00 G.ni. 31~~13:W 1, m. r-i ceptccl bet~vvcen the hour-s 0i ‘3:OO a.m. anal 3:OO pm, Lir~l\vt~~!n Ih(: h0ur5 0i 9::30 c1.m. ;Intl 2:30 p.m. ‘1,272 13tll’s (or ;-I”$~ 0i thy t0tdli JI-;I It2tcrccptd Any surrounding eletmvnts, such 25 I-,LIIIcII~I~~ 01’ lall tiec~, that block 1hv sun during 1hese limes Lvill severely limit they use oi solar en.ergy ds a heating l source. ,, ’ ‘i / Thie Recommenchtion ’ ’ To.take ad.vantage of the s’un in tlimates where heating is needed during Ihe winter, find the areas on the site that receive the most sun during the hours of makitium solar radiation&):00 a.m. to x:00 p.m. (sun time). Placing .the building in the northern po&tion of Jhis sunny area will (1) insure that-the, outdoor areas and gqrdens placed to the south. wil,l have adequate wir$!er sun and (2) help minimize the:possibility of shading the building in* ,the future by off-site developments.., d fr il , -,_ f . 0’ f ,r ” d 73 ,I . I ‘1 1: : - ,-The Passive Solar, .Energy Book ) F .’ iI ” .,‘&*I .>* L cI ‘. ! : e- , _ ” . s ,. _’ 1;. ‘-. _ -. I _--.-. . I’ .,,:, m g. -G - Fig. IV-la r a s D. T ;A 0 a1 -. . ,I.. , . 6’ c . ., 0 T” --,‘-. Whkn.deciding OYJthe exact location for the *building within a sunny area give the building a rough shape--BUILDING SI--!APE AND ORIENTAfl(SN(2j~ _’ .-.-_-_ and place the etitrance of the building so that .it,receives the greatest protec- ’ ’ ,,;ion f(om the cold winter winds-PROTECTED ENTRANCE(5). . A*%,’ ’ ( ‘\ . \ 7 :;!; ’ ;_ !. * 5% The Infqr$ati,&,b, ’ a . c- 1 ‘” .I :. .L -2 ’. * , -- :\ 7 1 ‘1 - 9. To take advantage of-the winte,r sun,.first the sunny places on t{leGsite n&d to ” / ,, be Located. To do this, explore.the site and determine which.places have an *. “. I open vie.vv to the sou;th ith sw,n chart (chap., 5) is minimum blockage of-the low winter ‘sun. The useful in visualizing site ob,,structions that,block . j \ d”irect tin from reachi .’ * sun chart for your latitude. y ,point on -th<‘site. Remkmber -to use the correct ,,’ I IDI . . . ,. 4 If the skyline to the south is low with no obstructions such as tall trees buildings or abruptly rising h-ills, then the following p?‘ocedure>is unnecessat$ as all points on the site-will receive sun during the winter. If there are obstructions . ” then the skyline should be accurately plotted on the ;un chart to determinethe Y-’ n B __,.(_’ extent of solar blockage.. (See “Plotting the Skyline” in chapi’5.) ‘J x 0; .” \1 ’ ;4, ~ * \\. , <. - ; *+%..&-. , a \\ ~’., * ,i.‘. * ;” ,__ ‘‘,v ‘I o I , /,’<, i -$g. IV-lb:. ~,Using’t,he sun chart @,visualize s&r obstruct&g. .* = 0 Lb. , I c, “% .7) , :’ rban site;‘s’urioutidY& by’ large gbstructions; it-may not be feasible to plot the skyline since the skyline cha&& drastically when seen from .differ:’ .c F‘ ent points on the site only a few fegt,awa$rom each other. ‘In this-situation a ‘ .;’ I r.’ simple :threeYdimensional mod#of the and its surroundings shoyI’d be !&I 1built. This mo,del, when used in conju n with a sundial, wil.1 hellj qy6u ’ *.,*: IL determine the best building locations with exposure to the winter sun. ‘;. ., IL * t 0 I ,< I ._ I.. _’ When deciding ok the exact l”ocgtibn oftthe ‘building, yo,u musp also choose .. the: place forrtheoutdoor spaces next to the building. Christopher Alexandqr, in <( D ,.. , !,‘:y+?-* ( y . .,- ’ fil t ,, .--..I $gQ, ,;- 1”,,. __y’*&, ‘..:..+; 0 I ‘_ ,; ‘,* ‘- . .d . “/ , ( ~ j1 ’ I / _‘ _. 75,! i /_’ 1 i , . , “,, ! ’ )I ‘q . I! ,i I,l.“‘9 x i: :..: ; 0: ., .- .I. ,i’ I’ . _ _____-.-A-.--- ---p---i- ---c---..--- - r -2 ----- -~hI 0 ‘-7 ‘Y. I F \ - Th>. Passive Solar Energy B,ook, 0 7, ’ c. . ‘a \‘:“-i . ‘. ._-_ c _ .- = _.__ .‘..--. : ----: --.-.-. ~-.*-+A ,.‘k “,..; .I . 1 *t. ’ I . -3 ‘.. L <. vJ 6.. ,f * 9. _ L . ’ c> ’ .-. r-7 .. ;. . . ’ + <; e :I ‘, - i 3 . j.. ‘.I ..” 1. ButMing location ,- _ 1 J ,$ . “‘\- F .s 1 * UQ j. .-Q ” ’ -p , A survey’of a residential block in -Berkeley,(?alifornia, confirms this i ‘. : problem dramatically. Along Webster Street-an east-west street-38 . s’ t. - of 20 persons interviewed ‘saiOd Lhey used only th: sunny parts of ..._. * --I . their ya@.s. Half ,of tljese people living on the north side of the 6 street&-these people did not use their batkyirds at all,* but would ; *. ‘. - +1c,7-’ sit in. the fro,ht yard, beside the sidewalk, to. be in the south sun. L I h ‘r ..W, Note ’ .,I’ ,, F ., ~ 4.f %,.,.,i \‘J’,I , ‘44’.NL \‘?~. <” ’ f,, ,. d’ /71 ~111-6._Y j ‘1 i -. L 9:1 ^_? 81 i _I k cI \,’ Fig/.ly+2b: .Sol~r radiatihn imp&‘& different latitudes. i, ‘.-+ I -_ % - , ’ “., .. *‘. i .~. j : \ :( . \, fi’ * a.I i - ; * 0 t o%a;\ 8-p. ’ $q B&&1\ .”8 \ I, . 2 ‘, =, . pd- ‘1. ,, .‘j: Ji. ?a* A ., -, : ‘. i P . -py _ , . . ,’ *. \, :1,.*f.. ‘X\. ,: .;..,..,,~;y(. i B *I/,,. I pi.. 2 ’ 1 h -’ $ I- ._a \ -. -. n: _‘ .< r’ .::. i .i. .- . * ia ,’ , ,B .’ 4#. “.’ r6 :.;, i ! id 0 , 1. ic The Passive Solar Energy Book . -_ ; * . .. summer with less efficiency * \han the square one. c I G ” 3. The ‘optim’rrm shape t&s In even/ CXF tatt:rlimates 4-f in a f&m ;; elongated somewherq along the east-west direction. By looking at the rtidiation impacts on the sid,es of a bui,lding, at different . latitudes, both in wibter and summer, Olgi/ay:s conclu’sions become rradily apparegt. .- . ” A ,,building elongated along the e&t-west axis’exposes the longer south side of ’ the building to r&xi’mum heat gain durin’g the winter months, while exposing th@ sh,d rter east And vwest si$s to .maximum *heat gain in the summer, when the sdn is’ not wanted. tn. all northern latitudes (32” to 56”), the squth side -. of theibuilding receives nearly 3 times a5 much solar r;adiatlon in the_ winter * IY 7 .I Phofo IV-26 ’ Housing units at&&d along the east-\&t axis. Y ~. .^ *Author’s italics. 3 tAuthor’s addition. A * : -,” c. .. -( 2. uilding Shape and Orientatioy roof and east and w&‘t sides ot the bulId;ng 130th In jurnmer and IvIn\c’r th,cJ . north side of th’e building reqelv.cJs, vc;r\j IIEtti~ ~acl~altc~r~. BCJSI~(T t)cJing, an -efficient shqw, the largtl southern CXTI~F,U~Pi5,1tltlal tor th(~.coIIc,(.-1”1(,nr)i sol,11 L r;ldlntion. Major collec’tlng C~r~~Cfa~~lfi~nq 01 ihi. ’ t~i~il~lin~ c)r~~ntc~l to lhtk .‘+jJ’ south iv111 Intercept the nla\lmum anlount ot so/,jr ra(jl,lt[on C~~;l~l;~l-~t(~lu~ring” ttie wntcr months. ii , ,~ . -, 1-. _../,” At all latitudes, althougtl bulId1ngs t~l~ngat~~ ,~long the ~astx\lest ndc upon thtl cj~rn,itt> ic,rrl’e i icneral principles ;a,; be upc,s~‘ng,I ni1n~r9uni Q ‘6 8. . J r.;.p .,,.,,,,..lt perxetration. , 11’ u -J b 0 .: ,.>f#,‘a ’w 0 0 . Th.e PpssivC Solar Epergy Bpok 1 ” _) f ;3 v 0’ i.; p” . ---I , of sujce area to a‘ harsh environ‘ment is desirable. In temperate (New York’ /City) climates there is more freedom of’building shape withbtit sev $excessive heat gain or loss). In hot-humid climates (Miami;), buildi be freely elorigated i,n.the’eist-west direction. In”,this climate because of ibtense sumser solar radiatioq on the east and n/est;si?{es; bulldings shaped ‘along .,, the north-sou!h axis pay a severe penalty in eJnergy consumptron (for cooling). - ’ , In all climates, atLachedu‘ni’ts’&Bch as roiv houses) with Cast and \Gest common walls qre most’ efficient since only the end units are ei$osed on the east or west face. ’ :. -4 I F Y j\\ Assuming that a bvilding elongated ayong th,e easf-Lyest axls Is’:c.ompatibie lvith oiher site and design considerations, lo give the bullding a rough form tve need I “,to determine the width of th.c> building. When the .prlmdry jou;ce ot’ $tinlight entering a~sr”,ace is through south-facing \&indows, ll1cn ihra Ck![,l~l, oi spaces along the souIh wall 0i thq building should no1 ~scc/ed El/i times the: height a of the windows frorn the floor. ThiS assures that sunlight will pcknctrate the en tire spacer. a 0P Also, this rule of thinib prqvides fog. the a‘dequatc daylIghting of interior sppces. According to.siu,dies don’e by the Illuminating Engineering- Society, the ’ epth 4 of ‘a space for idequate natiral i.llumination should be limited to he range of 2 to 2% times the windo.w height (‘from t,he floor to the top of the fi i indow). For an average window heig’ht of 7 feet, this means a ma%imu& -pace depth of 13 to 18:feet. For Thr+rmal Storagk wail and Attached seen- 0 hous&Systems, room depth is limitid t& 15 to 20 feet. This is rJ d -ma,xi tie urn distance for effective heating irom n radiant wall. % I 1 -t ‘If fhe major spaces of the bhilding’are, placed along the’syuth wall (fo;‘suX _ ! \. * _ Li light requirements) and the buffer spaces placid along the north wall, then th,$ ~ maximunl dept;h df the building will be roughly 25 to’-30 feet. Spa&es which 1, ’ need to be deeper orI do not want large south-facing. lvindows with direct sue ,y shining directly through the space can let the sun ‘in ihrotigh south-faci$ clerestory window!! or skylights. :Admitting<.the hajor;portion of sunlight into ’ .a space through- the roof h.as the a.dvantage of allawir?g flexibility ic distributing $ght ahd heat,to different parts of a space-CLERESTORIES AND SKYLIGHTS c (10). This allows for the maximum flexibility in locating thermal mass within a . s+te--MASQNRY HEAT*STORAG~~l1), INTERIOR WATFR WAL,L(l2). ifK ,B _ __ _ _ _,._ .,-----_ -k------y- % ., _ n ., 3 -. ,I) \ ., v . . @.. \ 1 Ir ,I Y- 1 2 _ .J , 1 4 . .r . .....*- .‘.. . d / 7 i .e. ., \ . -. = _* _ - _ r *r “’ --.___ P , T-T.... -_ ii’ 1 . ;-n‘, . &. y,y .’ , -> 0 ----.. : ‘.: ”’ e n ‘. - * r 1. ?-- m’ ----___ ~ _‘> * : 8“’ &ek;hbugh a building is l&ted in the norlhern portion of a sunny site BU’tLDING LOCAT-EON(l)--the adjoining outdoor spaces to the north- need ‘. . sunlight to yak6 them alive. When giving the bu-ilding a iough shape, .I 1 >I .~. “,-~&hikcom’$wndation I ‘\ ._ ~-- I ..~.~~. , -~...~ \’ ,j- ,, : .,..“’“’ -- . y, IO, *,Shape thCbuilding so.,that its north si& sloies tow&$ the ground. When : 2.. ‘* , D ,pqSsible btii!d’ iyto the side of . \.\ . r\ _a “., I the ‘poflh %!ce of a byilding’ .j - _ ds the’lieight of ttie norfh wali’is reduced,‘$he -- .~1’ .\ ;: ‘>in winter is sh,btiened. Use‘.a light-colbted -- y’ 5- ._ nqith’of the’ building to reflect sunlight into _._-_. _--. sp&& “, , . , r. . ,. _. Q’ ‘, .: ‘. “;~. :- .-. c L .d -’ .. * I.> /’ -, D I r. 86 .; + ’ ;,a ,@--. , , ’ .y .-A i .,-. ‘r 1,. a. -: y . .:’ _ . -“’ / ran.--- .\ ” :’ ,. 1 - _ .. 3, , , :?:.‘.I.- . ’ _ 3. ,,r ’ j *,, .- *’ -4.r ..’ - -1 I . .- : r. I s .:-. - , - ” . il -:-q,. I ,’ . !.L . .a pg$..~ ‘- . :. .. j 5 ? J.. ., . \ . -$ , ‘: ‘_ ._I ” 8, ,i’f’ ., -. . . ,. ._;I, I _ 3. North Side ‘-‘_ ; .,:.:: +.,,,d ‘z-F‘-.i,._,:’ ‘I -. , >’ .’ : - e ..;-j&7;- ;.; _ -r ,, L .. 5, - Fig. IV-3a 0 I-:! 7 G r> ‘. ,___-. _. -. *\\.““, . ‘S .~ r .... l * ;,,q l a . ... 9 ,\ Ya Locate spaces in the building that have small- lighting and heating requirc_ments to the north. These spaces act as a buffer between the living spaces andf the cold north face of fhe building-LOCATION OF. lNDOOR.SPACES(4). ’ I .. . The\ Infdrmation , ^I., I. _.< k 1, 4 - . . ;’’ ,Spac.es in continual shade for most of the winter are wasted-because pkple 1.’do not use them. . ... I i _ 3 i ,:’ 0 L ,,_,i:,,There are ways, though, to mal;‘e these places alive and useful. For example, u sjting albuilding into a south-facing slope or berming earth .against the north wall &.duces or, eli.minates the shadow cast by the building. Besides providing sunlight‘to the north side, covering a north wall ‘with’Te.arth reduces heat loss , ” ‘ ,. * . d i> a7 _I \ ). .* I :\ ’ 1 .% : : . I _. -. United States. walkway. To p,rotect these outdoor area% In winter, plant a dense row of evergreen trees and shrubs or tocaMp solid chstruction (kyat1lLt.o blc& the-~-_ - --_ prevailing winter winds. P 88 ~I+ - ~,