Fundamentals of Building Energy Dynamics SolaHre atT echnologiFeusn:d amentaanldAs p plications Charles A. Bankston, editor in chief 1. History and Overview of Solar Heat Technologies Donald A. Beattie, editor 2. Solar Resources Roland L. Hulstrom, editor 3. Economic Analysis of Solar Thermal Energy Systems Ronald E. West and Frank Kreith, editors 4. Fundamentals of Building Energy Dynamics Bruce D. Hunn, editor 5. Solar Collectors, Energy Storage, and Materials Francis de Winter, editor 6. Active Solar Systems George Lor, editor 7. Passive Solar Buildings J. Douglas Balcomb, editor 8. Passive Cooling Jeffrey Cook, editor 9. Solar Building Architecture Bruce Anderson, editor 10. Implementation of Solar Thermal Technology Ronal Larson and Ronald E. West, editors Fundamentals of Building Energy Dynamics edited by Bruce D. Hunn The MIT Press Cambridge, Massachusetts London, England © 1996M assachusIentsttsi otfuT teec hnology Allr ighrtess erveNdo. p arotf t hibso okm aybe reproduicnae ndy f ormo rb ya nye lectronic orm echanimceaaln s( includpihnogt ocopyriencgo,r dionrig n,f ormatisotno raagned r e­ trievwailt)h opuetr missiinwo rni tifnrgo mt hep ublisher. Thibso okw ass eitn T imeRso manb yA scoT radTey pesettLitndg. H,o ngK onga ndw as printaenddb ounidn t heU niteSdt atoefsA merica. LibraorfyC ongreCsast aloging-in-PDuabtlai cation Fundamentaolfbs u ildeinnegr gdyy namic/se ditbeydB rucDe. H unn. p. em. - (Solhaera tte chnolo4g)i es; Includbeisb liograrpehfiecraelan ncdei sn dex. ISBN0 -262-082(3h:8c -a1l kp.a per) 1.B uildings-Ecnoenrsgeyr vat2i.So onl.ah re ati!n.gH .unn, BrucDe. IIS.e ries. TJI63.5.B841F98966 696-dc20 95-46158 CIP Contents Series Foreword by Charles A. Bankston vii Preface ix Acknowledgments Xl 1 IntroducEtnieorng:Uy se inB uildings Bruce D. Hunn 2 PatteronfEs n ergUyse inB uildings 39 Arthur H. Rosenfeld, Mark D. Levine, Evan Mills, and Bruce D. Hunn 3 CharacteriozfaE tinoenr gPyr ocessiensB uildings 113 Robert D. Busch 4 MethodosfE nergAyn alysis 219 Robert D. Busch 5 EnergCyo nservaantid oMna nagemeSnttr ategies 339 P. Richard Rittelmann Contributors 517 Index 521 Series Foreword CharlAes. B ankston This series of twelve volumes sumam rizes research, development, and implementation of solar thermal energy conversion technologies carried out under federal sponsorship during the last eleven years of the National Solar Energy Program. During the period from 1975 to 1986 the U.S. Department of Energy's Office of Solar Heat Technologies spent more than $1.1 billion on research, development, demonstration, and technol­ ogy support projects, and the National Technical Information Center added more than 30,000 titles on solar heat technologies to its holdings. So much work was done in such a short period of time that little attention could be paid to the orderly review, evaluation, and archival reporting of the significant results. It was in response to the concern that the results of the national pro­ gram might be lost that this documentation project was conceived. It was initiated in 1982 by Frederick H. Morse, director of the Office of Solar Heat Technologies, Department of Energy, who had served as technical coordinator of the 1972 NSF/NASA study "Solar Energy as a National Resource" that helped start the National Solar Energy Program. The purpose of the project has been to conduct a thorough, objective technical assessment of the findings of the federal program using leading experts from both the public and private sectors, and to document the most significant advances and findings. The resulting volumes are neither handbooks nor textbooks, but benchmark assessments of the state of technology and compendia of important results. There is a historical flavor to many of the chapters, and volume 1 of the series will offer a comprehensive overview of the programs, but the emphasis throughout is on results rather than history. The goal of the series is to provide both a starting point for the new researcher and a reference tool for the experienced worker. It should also serve the needs of government and private-sector officials who want to see what programs have already been tried and what impact they have had. And it should be a resource for entrepreneurs whose talents lie in translating research results into practical products. The scope of the series is broad but not universal. It is limited to solar technologies that convert sunlight to heat in order to provide energy for application in the building, industrial, and power sectors. Thus it explicitly excludes photovoltaic and biological energy conversion and viii Series Foreword such thermally driven processes as wind, hydro, and ocean thermal power. Even with this limitation, though, the series assembles a daunting amount of information. It represents the collective efforts of more than 200 authors and editors. The volumes are logitally divided into those dealing with general topics such as the availability, collection, storage, and economic analysis of solar energy and those dealing with applications. The present volume is one of five volumes in this series that deals explicitly with building heating and cooling. However, urilike the others, volume 4 focuses on the buildings, building equipment, and the energy conversion and heat transfer processes that take place within the build ings, rather than the use of solar energy to meet the needs of the buildings and their occupants. The reader may think of this volume as covering the demand for energy in buildings, volumes 6 through 8 as covering the means of supplying solar energy to meet those demands, and volume 9 as covering the architectural integration of solar energy supply technologies and building technologies. As implied by its title, volume 4 presents the basic physical principles and equations that describe the flow of energy into and within building structures, as well as the analytical methods, algorithms, and computer programs used to calculate those energy flows. It is not, however, just a textbook on thermodynamics and heat transfer. It is a comprehensive assessment of the state of building energy technology as a result of the many advances in energy efficiency made, in part, as a result of govern ment programs in energy conservation and solar energy over the past two decades. The volume characterizes the energy demand of the national building stock and of individual buildings, presents the results of research on the energy processes and the methods and tools used to analyze them, and discusses the broad range of strategies developed to control and mini mize energy consumption. All this material is presented in the context of providing a basis for the application of solar energy technologies to building loads. Preface Because solar heat technologies are particularly applicable to residential and commercial buildings, an important element in documenting the Na tional Solar Energy Program is this volume, which assesses the significant advances in building energy system technologies made from the early 1970s to the late 1980s. The Office of Buildings and Community Systems of the U.S. Department of Energy conducted extensive research programs in a wide range of building energy technologies and design strategies. This program was a parallel effort to, and was coordinated with, the National Solar Energy Program conducted by the Office of Solar Heat Technologies. In large part, this volume documents this parallel effort that deals pri marily with the issue of energy conservation in buildings. This volume aims to assess the state of our knowledge of how and why buildings use energy, and how energy use and peak demand can be re duced. Its authors seek to provide a basis for the integration of energy efficiency and solar approaches, because solar-energy-related capital costs are reduced, and the fraction of the load supplied by solar is increased, as the load is reduced. Thus the information presented here traces the de velopment of the state of the art of building energy systems, and the analysis of those systems, so as to characterize the demand side of solar applications in buildings. This will provide a basis for determining what portion of a building's energy requirements could potentially be met by solar energy. How that energy use is met by solar is the subject of there maining volumes in this series. This volume is not a textbook on building design. Its purpose is to provide a thorough assessment of the state of the technology of building energy use, with an emphasis on technological developments that were influenced by federal research and development programs during the 1973-87 period. While federal programs contributed much to the devel opment of our knowledge and understanding of building energy dynam ics, this technological development has for decades been the primary focus of the American Society of Heating, Refrigerating, and Air-Condi tioning Engineers (ASHRA E). Thus much of the literature cited in this volume is that of ASHRAE. Because the intent of this series is to sum marize research, development, and implementation of solar energy tech nologies carried out under federal sponsorship in the National Solar Energy Program, the focus of this volume is on the energy technologies applied to buildings only in the United States. Bruce D. Hunn Acknowledgments This series was produced as a result of the vision and leadership of Fred­ erick H. Morse, who for many years was director of the Office of Solar Heat Technologies in the U.S. Department of Energy (DOE). This vol­ ume is dedicated to him and to the legacy of solar energy development that he fostered at the DOE. As editor in chief, Charles A. Bankston provided unwavering support with uncommon skill and patience through­ out the development of this volume; he made this volume possible. John A. Millhone, as director of the Office of Buildings and Community Sys­ tems in DOE, provided the leadership that resulted in much of the re­ search documented here. In addition to the authors of record, I am grateful to two inc;lividuals who gave considerable time to this project as preliminary authors but who were unable to continue in that capacity because of other more pressing assignments and duties. Larry W. Bickle of Tejas Power Corporation in Houston, Texas, gave us an excellent start and basis for chapter 3, and Joseph J. Deringer of The Deringer Group in Berkeley, California, con­ tributed significantly to chapter 2. Thanks also to Nathan Martin of Lawrence Berkeley Laboratory, who assisted in the preparation of the final version of the residential portion of chapter 2. I especially thank each of the authors, who contributed invaluable expertise and knowledge de­ veloped over many years of dedicated research. I am also grateful for the assistance of the professional and insightful peer reviewers for this volume, who offered wise and helpful comments on drafts of the several chapters. These reviewers include J. Marx Ayres of Ayres Associates; John D. Cable of Hagler, Bailly and Company; Eric Hirst and Daniel M. Hamblin of Oak Ridge National Laboratory; David Harrje of the Center for Energy and Environmental Studies at Princeton University; Robert W. Jones of Santa Fe, New Mexico; Ted Kurkowski of the U.S. Department of Energy; Tamami Kusuda of the National In­ stitute of Standards and Technology; Richard L. Merriam of Arthur D. Little, Inc.; Thomas M. Sayre of the Sizemore/Floyd Partnership; Robert B. Shibley of the State University of New York at Buffalo; and Edward F. Sowell of Ayres Sowell Associates. Robert Jones was especially helpful in clarifying the focus of chapters 2, 3, and 4. Finally, I wish to acknowledge the expert administrative and word processing assistance and patient support of Alice M. Wilson of the Cen­ ter for Energy Studies at the University of Texas at Austin throughout the several years of this project. 1 IntroductEinoenr:gU yse inB uildings BrucDe. H uon 1.1 Introduction 1.1.1A bouTthi sV olume Wec adne sbiuginl dtihnaagrtase sc omforbteaabultaein,fud us lea,fn udl thautss eu bstalnetfsiosas lfsluiyeel ln erbguyot,n lwyh ewne h avae thorogurgaohsf hp o wa nwdh yb uilduiseneng esr Tghyei. n toeftn hti s voluimste o d escbruiibleed nienrgug sype a ttetrnhtseo, o alvsa ilable toa nalyeznee rugsyea ,n dt hpeo ssibfioulrsi ittnihgeae stn ermgoyr e efficieOnutrgl oya.il st op rovaib daes fiostr h ien tegroafet nieorng y efficieanncsdyo laaprp roabcehceassuo slea r-enecragpyic-toraseltl sa ted arree duacnetddh ,fe r acotfti holeno asdu ppblyis eodli aisrn creaass ed, thoev erlaolaildsr educWeewd i.tl rla tchede e veloopfmm eondte rn building enaenrdog fyt haesn yasltoyefstm ihsso,s s yes tienmo sr,d er toc haractthedere imzaseni ddo efs olaaprp licianbt uiiolndsTi hnigss . wiplrlo vaib daesf iosdr e rtmeinwihnagpt o rtoifao b nu ilsde innegr'gy requirceomueplnodtt se nbteim aelbtly sy o leanre rHgoywt. h aetn ergy usieas c tumaelbtly sy o liatsrh s euj beocfto thveorl umients h siesr ies. 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Becatuhsieen toeftn htsi esr iitseo ss arirzees eadrecvhe,lo pment, umm andi mplemenotfsa otleianoren r tgeyc hnoclaorgroiiueeutsdn dtehre NatioSnoalElan re rgy Ptrhofego rcoauftms h, vi osl uimosen t heen ergy technoalpopglitieobe sud i ldiintn hUgens i tSetda tWeecs a.on n layd d