The Passive Solar Energy Book - Edward Mazria - 447pp [PDF]

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by: Edward Mazria Published by: .. Rodale Pfess, Inc. 331East Hinor Street Emmaus, PA 18049 USA

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;’ BY EDWARD MAZftlA F-7 -1 i.

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by Edward

Mazrja

All rights reserved. No part of this publication may be reproduced or transmitted in any form{ or by any means, electronic ‘or mechadical,‘.includrng photoor any. information storage and copy, recording, retrieval system without the written permission of the publisher. ‘ S’ L * ” f3ookDesign hy 7 A lcpley

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Mazria; Edward. The passive solar energy book.

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Bjb;liography:. p. Includes index, 1. Solar energy~ 2.‘Solar heating. I. Title. 78-21656 696 ‘\ TJSiO.M32 1979b ISBN,O-87857-260-0 (Hardcover) I BN O-87857-237-6 (Paperback) $ 1 hardcover 9 4, 8'10

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SOLAR WlNDg>WS c “, CLERESTORIES AND SKYLIGHTS MA&ONRY HEAT STORAGE JNIERLOR. WATER -WALL.-

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Thermal Storage Wall Systems’ 13. S[ZIbk THE WALL i4. WALL DETAILS

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15. SIZING THE GREENHOUSE 16. GREENi-lOuSE CONNECTIONp

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Robf Pond Systems bj K,enneth 1. Haggard

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:, 21. ,dXMEitilNC SYSTEMS ‘22. CLOUDY DAY STORAGE 23. MOVABLE lNSU\+TION 24. REFLECTORS ?, 25. SHADING DEVl‘i3ES

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26. INSULATION ON THE OUTSIDE 27. SUMMER COOLING V. , -.

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The Sun Charts--how the sun works, the cylindricdl ~ sun chart, sun charts, sun time, plqtting the skyline . . . The Solar Radia’fion Calculator--hourly radiatiov . totals, daily radiation totals, splar intensity masks ‘The Shading’calculator-p/ot’tirfg the sha$ng mask

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1. Perfocwa+ce Calcblations ’ 2. Percentaie of Solar Radiation Absorb&i 4. ,//. ,/,;I by Various Sdrfacqs, . =..>, )A&* ,’ ./3. Averqhe Daily Sol/wRad~iak5~ ’ + -3. )I, :y -2. ““2_.,- &ASeI$ge Daily Te/nperattires (“Fj in North r, ‘. i j . / id _.~ ii ..- \ ’ I Amqkica -‘;-~-- --_-_-:u 1 Ij* &jree-D.ays _,.,.:,. .,. .:.. _ .*r- ....-. -.-l’ I “, ..t.,.. “,. . I _,._ ,._ __ _ _ _ _ --’ 7 - - -._ _ .~-_.. -__i -.-- .._. _- - ----l- 6; -f&@r-&++%m’ ~1: .JY- A--_ . .‘~~-,. p-.--... _--.,.__ -- ._~.._~ 1..___ 7. Pqcentage of Ehhanceknt of Solar. H&t =* I * 7 l , @in with Speclillarf$flectors .* . 8. -C nveision Table’s I 9

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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. J -I want to especially thank: ....,. I

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Steve Baker who”‘worked”closely withme for t.wo years to genera!e. data ‘I *for the- formulation of the patterns and’ calculation p.rocedures. His ’ - %tsight and kno-w.ledge of’the subject add a dinet$ion to, the book that would otherwise be-absent. I am grateful not only for his contribution to the book, but for his support,and friendship during iti. production. j. A * .1 :* Robert Young who spent numerous hours assembling the .Appendix, producing the technjcal drawi.ngs and photograiphing,many of the build-. . y. 1 -ings.presented .in the book. i 4 Ir . .

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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 -, ~ an~d.he&transfer, .. _~~ f c;:-.. .~~1.’ ., .s b .

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Acknowledgments /. h-Haggard and Polly Cooper (of their patterns onr’oof

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oh Cettings’for his beautiful photographs. - P. I. : &&“l’Stone~ fbr’her early .and ceagement. i

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c . . * . 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 by Christopher Alexander, Center for Envi’ronmental . ,’ .

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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 abandon these Ion&standing con-’ P .f .; siderations. II I ‘\ / I

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Architecture in the twentieth century has been characterized by an emphasis environGment this on technology to the exclusion of other’values. In the built concern manifests‘itself in *the materials I 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 nts. In a ,sense,, we have become processes to satisfy our comfo~rt since windows.must be inoper-prisoners of complicated mechanical able 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 1 coast. 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

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.~ require ho external energy input and produce no p‘hysical by;products or waste. Si.nce solar,energy is c0nyenientty.distributed.b alI’pa$+ of the globe, expen# ‘sive transportation and, distribution netwolk$ of energy are also eliminated. .d * .I r Jr. k-t ; .A

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Shce a buildi’ng’or some element of it is the passive system’; TheAappllcatipn 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 difficult’ ’ to add a passiv,e system to a buildjng once. it hasiheen &signed.

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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 , 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 heat, loss and gain calculations,.since the building wfll change, amany times 1 I< before a design is complete. =? < _. n -3,!: ?I > The- basic purpose of this book is to make technical information acchssi I?” e to 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 _i p -.. ’ design. The illustrations that accompany the text are intended to convey very. .tPchnical information in a.simple and clear format. sdp 4 /= Tiis‘book deliberately does not use pr;ofessional architectural and, ehineeringd * 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 LIS specific details., i ‘k . i .

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c f T$ allow, for change resulting&&new experiments and observation’, the book t. a way-that \permits ;he..&rder to in1prov.e and ad.d information ‘I e .is structured’in ..,* ( -‘Bsm&’ IS I earned about’ passive sys~&r~s.~ ~Since each element *of. a passive , .i .; syster?i.“.is treated separately’ in the text, ‘the. Eetetrieval of specific Pieces .of. 1.. ‘inform.ation is made easy. :” \ I .b m ,I * I \ ,5 ,e 8L c L .-.-. I. ’ .-. ‘. .?:,, all locations”betwer$n 28:” and 56” ,adapted to the same latitudes in ~ e I . the Sfuth,ern Hemisphere by simp.ly reversing the sea&s and reversing true \I ..... “I-I..,,..,.~“IYwI,*, ,,:,,,ubJ ,aemuy e * ‘, = I\. .’5’ ‘. .%..

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;\* most of ;he information you will‘need .’ building. Its contents: are ordered~ in applications to system design and I the fundamental c.oncepts of -1” It provides the foundation for k. \ ,.* < _

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&, The P&s&e; Sqlar Energy Book ; 3 . Y... c a_ A., L il i I_ ‘3 -,. -’ , d n T, --L _I. -... e.. given in the following chapters. ~Chapter’ 3 -;-- -...._und

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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 n around the sun.

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First, as solar radiation is absorbed by a/material, the at&orbed redistributd itself within the mateiial as ,it is’ passed or COru’p’uCTED between I mdlecu,les. Conduct$n: @‘the process ,in &ich heat ene\gy is transferred : ‘“’ _ betweT molkcu~eswjthin a substance, orbktween two substances in physical :.a ’ \, 1 _.__ contact-,, by-dil_ectmolecular interaction. The &qmer molecules bump info and I rjass some,of the+-vibrat&naI energy to adjacentrnolecules. The dilection of 1 \ heat flow is always frot?warm.to $‘ool.‘As the’molecules at the surface’ of a I material are heated by solar radiation, they $ass this energy to cooler adjacent++ ’ ‘Lmolecules dispersing the heat through the rr&$ialso th&dt. takes on a more . -ttwdh-e rate of h&t flow or the thermal co’&c@CtjVjt~ (k).of-a’ --, * , subst$nce is dep@ndent on the capability of its molecules’to sendh,and3receive ,_‘Xheat. 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 than wood. The more heat conducted from the hand, .A 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--__- --L . ’ Second, H ‘hate!ial will Yransfer h,pat &&gy from its kface’to the moiecules ‘0 .:7. --- ._ : of Gmt$!_u_ig-?-.by CONVECTION. ‘f;onvection is -defined.: as 0) the “:’ ‘, and a moving flui’d, ‘or (2) the transfer of .‘L-‘transfer of heat betweer&urface. ‘. . hea,! by: the movement of the molecules.-....I.. from a fluid to “another. __ onepo&t-in . ’ \ ‘,.;l-n-canv~ctiop pro&seS, heat again always moves from warm%-c&LA&e - o .‘.a ! . ;cool*m’olecules’of a”?luid such.as wate-ror air come into physical contact with a : .,, ;... ., ,.I. I!,’ ” yarm surface,,sdme of the’vrbrationaf energy at the surface &f the material is. : \..A ..\.‘... ~ -...L

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