Handbook of experiences in the design and installation of solar heating and cooling systems
DISCLAIMER 'mb book was pI.spued as an account of work tpolurored by an agency of the United States Go~mment. N&ha the United States Government nar my sgisncy thereof, nor any of th& mployees, makes my -tyt q m x s or h p k l , or assumes pay legal liability or responsabllity for the acc~rwy, eompastcm, or u r s f u h~ of any idormation, apparatus, product, or pmotrr birdolsd, or represent# that its wt would got ptivatw owned Refemice hodn to m y qmdfk commerd.i product, process, or d c e by
... ess, or d c e by trade' m m~, t n d e e , mu--, or o-, dar not n d y ooncthto or imply ts endonemen& en ti on, or Lvodug by the Unit& States Government or m y agency thkeeof. The view d opinjDm 42 authors e x p d busin do not n e m a d y state or reflect thorn of the United Stater Government or lay a@nq thereof." EXECUTIVE SUMMARY This handbook consolidates a large body of information on the experiences encountered in the design, installation, operation, testing, and maintenance of solar heating and cooling systems. A substantial portion of the information is derived from the U.S. Department of Energy's National Solar Data Network and other government-supported solar heating and cooling system projects. While these federally-funded projects may not portray the experiences of privately funded and commercial state-of-the-art solar systems, they do constitute systems which have sufficient data to allow for definitive conclusions to be made on the system's perfo,nnance and operation. In addition, problems of durability and reliability experienced in the federally funded programs are common to a wide variety of'solar systems, and vary significantly from the National Demonstration Program's experience only in degree and not in the specifics of different types of problems. This handbook details a large array of problems encountered, including design errors, installation mistakes, cases of inadequate durability of materials and unacceptable reliability of components, and wide variations in the performance and operation of different solar systems. It should NOT be inferred, however, that this cataloging of problems in solar system design and installation implies that solar heating and cooling systems are not technically or economica,lly feasible. In reality, the reverse is true; solar heating and cooling systems can be economically and technically feasible. Many well-designed and properly installed systems have provided significant energy savings and demonstrate the practical, technical and economic justification for the use of solar energy in reducing the use of non-renewable energy resources. The theme of this handbook might very well be: It works, if you do it right. Based on experiences of operating solar heating and cooling systems, it can be concluded that substantial savings in non-renewable energy resources can be achieved with the use of solar energy. Among the well-designed and properly installed systems evaluated in this handbook, the average energy savings were: Savings in Non-Renewable Energy Resources Type Solar System (million Btu/year p-~r square foot of collector area) Domestic hot water 0.22 Passive space heating 0.10 -0.29 * Active space heating 0.19 Active space cooling 0.03 Potential active cooling 0.11 * * The majority of solar heating and cooling systems discussed in detail in this handbook did not achieve the energy savings per square foot of collector given above. The major purpose of this handbook is, therefore, to present the reasons for the reduced performance of many systems and to provide a compendium of data which details the problems encountered by operating solar systems. The emphasis on problems should not be construed to imply that solar systems typically encounter more problems than do conventional HVAC systems. Rather, a discussion of problems may be as instructive and useful as a detailed report on successful systems.