eicker solar technologies for buildings英文原版太陽(yáng)能技術(shù)教程清潔能源工程教材

1、eicker solar technologies for buildings英文原版太陽(yáng)能技術(shù)教程清潔能源工程教材solar technologies for buildings ursula eicker university of applied sciences, stuttgart, germany originally published in the german language by b.g. teubner gmbh as “ursula eick preface the heating energy requirement of buildings can be redu

2、ced from todays high levels to almost zero if buildings are thoroughly insulated, passive solar gains through windows are used efficiently, and the supply of fresh air takes place via a heat-recovery system. however, all buildings still have an energy requirement for electricity and warm water provi

3、sion which cannot be met by passive measures. active solar technologies are especially appropriate for meeting this energy requirement, as the elements can be integrated into the shell of the building, thus substituting classical building materials and requiring no additional area. solar modules for

4、 photovoltaic electricity production can be built like glazing into all common construction systems, and are characterised by a simple, modular system technology. thermal collectors with water and air as heat conveyors are installed for warm water provision and heating support, and can replace compl

5、ete roof covers if the collector surface is large. for todays increasing air-conditioning and cooling demand, especially in office buildings, thermally driven low-temperature techniques are interesting; these can use not only solar energy but also waste heat. apart from electricity production, solar

6、 heating and cooling, solar energy is used in the form of daylight and thus contributes to a reduction in the growing electricity consumption. the intention of this book is to deal with all solar technologies relevant to meeting the energy requirements of buildings, so that both the physical backgro

7、und is understood and also concrete approaches to planning are discussed. the basic precondition for the sizing of active solar plants is a reliable database for hourly recorded irradiance values. new statistical procedures enable the synthesis of hourly radiation data from monthly average values, w

8、hich are available world-wide from satellite data, and also partly from ground measurements. for the use of solar technologies in urban areas, an analysis of the mutual shading of buildings is particularly relevant. solar thermal systems with air- and water-based collectors are a widely used technol

9、ogy. for the engineer-planner, the system-oriented aspects such as interconnecting, hydraulics and safety are important, but for the scientific simulation of a thermal system the heat transfer processes must also be examined in detail. the fact that with thermal collectors not only heat can be produ

10、ced, is pointed out in the extensive section on solar cooling. the current technologies of adsorption and absorption cooling as well as open sorption-supported air conditioning can all be coupled with thermal collectors and offer a large energy-saving potential, particularly in office buildings. pho

11、tovoltaic generation of electricity is then discussed, with the necessary basics for current-voltage characteristics as well as the system-oriented aspects. since photovoltaics offers particularly interesting building integration solutions, new procedures for the calculation of thermal behaviour mus

12、t be developed. for these new elements, component characteristic values are derived, which are needed for the buildings heating-requirement calculations. the book concludes with a discussion of passive solar energy use, which plays an important role in covering heat requirements and in the use of da

13、ylight. what is crucial for the efficiency of solar energy is the effective storage capability of the components, which must also be known in cases where transparent thermal insulation is used. linking an outline of basic physical principles with their applications is designed to facilitate a sound

14、knowledge of innovative solar-building technologies, and to contribute to their being accepted in planning practice. x preface this book is due to the initiative of my now retired colleague professor jenisch, who was always interested in solar technology, while working on classical thermal building

15、physics. his contacts with the german publishing house teubner led first to a german version of the current book, which appeared in 2001. within the department of building physics at the stuttgart university of applied sciences, solar technology is now very important. without the support of the rese

16、arch group on solar energy, the broad subject range of the book would not have been possible. i would like to thank my co-workers christa arnold, uwe bauer, volker fux, martin huber, guenther maendle, uli jakob, dieter schneider, uwe schuerger and peter seeberger for their input and support with man

17、y of the books graphics. i also wish to thank my theory colleague, professor kupke, for his various suggestions regarding the section on passive solar energy use. i am, however, most indebted to dr juergen schumacher for his continuous support, which extends beyond the books content. it was with his

18、 simulation environment insel, at an intensive conference in barcelona, that most of the calculation results were obtained. ursula eicker, stuttgart january 2003 abbreviations in the text a area m2 ar receiver surface m2 as sender surface m2 ac cross-section surface m2 c charge concentration kgh2o/k

19、gsor egap band gap ev g irradiance w/m2 geh extraterrestrial irradiance on horizontal plane w/m2 gen extraterrestrial irradiance on plane oriented normally to beam w/m2 gsc solar constant w/m2 gh irradiance on horizontal plane (global irradiance) w/m2 gb direct beam irradiance w/m2 gdh diffuse irrad

20、iance on horizontal plane w/m2 gt irradiance on tilted plane w/m2 i current a i0 saturation current a isc short circuit current a k extinction coefficient m?1 l characteristic length m le irradiance density w/m2sr lv luminance lm/m2sr nu nu?elt number pr prandtl number pac ac power w pdc dc power w

21、qu useful energy kwh r resistance w ra-g heat resistance between absorber and glas cover m2k/w rg-o heat resistance between glas cover and environment m2k/w re reynolds number rp parallel resistance w rs series resistance w sd shading factor for diffuse irradiance t temperature k ta absorber tempera

22、ture k tads adsorber temperature k tb back side temperature k tdes desorber temperature k te evaporator temperature k tf fluid temperature k tf,in fluid inlet temperature k tf,out fluid exit temperature k tg glas temperature k tg generator temperature k tsky sky temperature k to outside/exterior tem

23、perature k xii abbreviations in the text ti room temperature k tc condensor temperature k tdp dew point temperature k u heat transfer coefficient (u-value) w/m2k ueff effective u-value w/m2k uf heat transfer coefficient front w/m2k ub heat transfer coefficient back w/m2k ul heat transfer coefficient

24、 per metre length w/mk us heat transfer coefficient side wall w/m2k ut total heat transfer coefficient w/m2k v voltage v v(l) spectral sensitivity of the eye vc volumetric content collector litre vcc volume collector circuit litre voc open-circuit voltage v w width m ca heat capacity of air j/kgk cv

25、 heat capacity of water vapour j/kgk dh hydraulic diameter m g gravity constant m/s2 q elementary charge c h heat transfer coefficient w/m2k hc convective heat transfer coefficient w/m2k hc,w convective heat transfer coefficient due to wind forces w/m2k hr radiative heat transfer coefficient w/m2k h

26、e evaporation enthalpy kj/kg ho enthalpy outside air kj/kg hl enthalpy liquid kj/kg hv enthalpy vapour kj/kg kmax photometric equivalent lm/w m avalanche coefficient pa pressure dry air pa pw pressure water vapour pa v velocitym f luminous flux lm, heat recovery efficiency a optical absorptions coef

27、ficient ai temperature coefficient of current k?1 av temperature coefficient of voltage k?1 b orientation angle from horizontal b heat expansion coefficient k?1 d sheet thickness m e emission coefficient n kinematic viscosity m2/s r concentration of rich solution p concentration of poor solution h e

28、fficiency reflection coefficient t transmission coefficient contents preface ix abbreviations in the text xi 1 solar energy use in buildings. 1 1.1 energy consumption of buildings.1 solar energy use in buildings 1.1 energy consumption of buildings buildings account today for about 40% of the final e

29、nergy consumption of the european union, with a large energy saving potential of 22% in the short term (up to 2010). under the kyoto protocol, the european union has committed itself to reducing the emission of greenhouse gases by 8% in 2012 compared to the level in 1990, and buildings have to play a major role in achieving this goal. the european directive for energy performance of buildings adopted in 2002 (to be implemented by 2005) is