Best Practice Catalogueon Successful RunningSolar Air-Conditioning Appliances
EIE/06/034/SI2.446612                               SOLAIRWork package 2: Market review and analysis of smalland medium si...
WP2 Preparation of a web based database of best available examples                Best Practice CatalogueThis report was e...
WP2 Preparation of a web based database of best available examples   Best Practice Catalogue1        IntroductionIn nearly...
WP2 Preparation of a web based database of best available examples   Best Practice Catalogue2        TechnologiesThe focus...
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WP2 Preparation of a web based database of best available examples       Best Practice CatalogueFigure 2.4a Examples of sm...
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WP2 Preparation of a web based database of best available examples   Best Practice Catalogue  Components of the Ammonia/Wa...
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WP2 Preparation of a web based database of best available examples    Best Practice CatalogueSolar cooling system at Fraun...
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WP2 Preparation of a web based database of best available examples   Best Practice CatalogueScheme of the Desiccant Evapor...
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WP2 Preparation of a web based database of best available examples   Best Practice Catalogue  Heat production sub-system o...
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WP2 Preparation of a web based database of best available examples   Best Practice Catalogue Solar Info Center SIC, Freibu...
WP2 Preparation of a web based database of best available examples     Best Practice Catalogue   Installed solar driven li...
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WP2 Preparation of a web based database of best available examples   Best Practice Catalogue5        Solar cooling: exampl...
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WP2 Preparation of a web based database of best available examples      Best Practice CatalogueReferences[Henning, 2006]Ha...
Supported byThe sole responsibility for the content of this publication lies with the authors.It does not necessarily refl...
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Best practice catalogue_en

  1. 1. Best Practice Catalogueon Successful RunningSolar Air-Conditioning Appliances
  2. 2. EIE/06/034/SI2.446612 SOLAIRWork package 2: Market review and analysis of smalland medium sized solar air-conditioning (SAC)applicationsTask 2.2: Preparation of a web based database of bestavailable examplesBest Practice Catalogue June 30, 2008 Version 1.0 1 Introduction ............................................................................. 3 2 Technologies ............................................................................ 4 2.1 Chilled water systems.................................................... 6 2.2 Open cycle processes .................................................... 9 2.3 Solar thermal collectors ............................................... 11 3 SOLAIR database of solar cooling and air-conditioning.................. 12 4 SOLAIR Best Practice Examples ................................................ 13 4.1 Best Practice Examples: AUSTRIA ................................. 14 4.2 Best Practice Examples: FRANCE................................... 21 4.3 Best Practice Examples: GERMANY ................................ 28 4.4 Best Practice Examples: GREECE................................... 42 4.5 Best Practice Examples: ITALY ...................................... 47 4.6 Best Practice Examples: PORTUGAL ............................... 53 4.7 Best Practice Examples: SPAIN ..................................... 57 5 Solar cooling: examples on advanced approaches........................ 62
  3. 3. WP2 Preparation of a web based database of best available examples Best Practice CatalogueThis report was edited by: Edo Wiemken, Fraunhofer ISESOLAIR is co-ordinated by target GmbH, GermanyPartners in the SOLAIR consortium: AEE – Institute for Sustainable Technologies, Austria Fraunhofer Institute for Solar Energy Systems ISE, Germany Instituto Nacional de Engenharia, Technologia e Innovação INETI, Portugal Politecnico di Milano, Italy University of Ljubljana, Slovenia AIGUASOL, Spain TECSOL, France Federation of European Heating and Air-conditioning Associations RHEVA, The Netherlands Centre for Renewable Energy Sources CRES, Greece Ente Vasco de la Energia EVE, Spain Provincia di Lecce, Italy Ambiente Italia, ItalySOLAIR is supported byThe sole responsibility for the content of this report lies with the authors. It does not necessarilyreflect the opinion of the European Communities. The European Commission is not responsible forany use that may be made of the information contained therein 2
  4. 4. WP2 Preparation of a web based database of best available examples Best Practice Catalogue1 IntroductionIn nearly all European countries, a strong increase in the demand for buildingcooling and air-conditioning is detected and predicted for the following decades.The reasons for this general increase are manyfold, such as an increase incomfort habits, currently still low energy costs, architectural trends like anincreased fraction of glazed areas in buildings and last but not least slowlychanging climate conditions. This rising demand for cooling and air-conditioningin buildings involves unfavourable fossil fuel consumptions as well as upcomingstability problems in the electrictity supply in mediterraenean countries, which inturn demands for costly upgradings of the grids to handle electricity peak powerdemand situations.Thus, improved building concepts, targeting on reduction of cooling loads bypassive and innovative measures, and the use of alternatives in coverage theremaining cooling demands of buildings, are of interest. Solar driven or assistedcooling is one of the possibilities to provide acively cold.In the context of the SOLAIR project, solar cooling or solar air-conditioning isused for solar thermally driven processes. Solar cooling in this sense may con-tribute to - replacement of fossil fuel demand by use of solar heat and by this, contributing to the European policy targets on the increased use of renewable energies; - reduction of greenhouse effect emmissions through both, savings in primary energy and avoidance of environmental harmful refrigerants; - support in stability of electricity grids by less electrictiy energy and peak- power demand; - optimized use of solar thermal systems through use of solar heat for combined assistance of space heating, cooling and domestic hot water preparation.The SOLAIR project provides several materials on solar cooling, adressingdifferent levels on information. Within this catalogue, Best Practice examplesfrom the SOLAIR database are presented. Many of this examples went intooperation less than one or two years before the compilation of this catalogue,long term operation experience can not be expected so far. Thus, the definition‘Best Practice’ refers here to an appropriate system concept and to promisingapproaches of solar cooling. The catalogue aims to present the applicability ofsolar cooling technologies within different building environments, at differentlocations and with different technical solutions. In the beginning, a brief reviewon solar cooling technologies is presented.More information on the SOLAIR database is provided in the Cross-country reportof the review of available technical solutions and successful running systems,prepared in SOLAIR and accessible at www.solair-project.eu. 3
  5. 5. WP2 Preparation of a web based database of best available examples Best Practice Catalogue2 TechnologiesThe focus in SOLAIR is on solar cooling and air-conditioning systems in the smalland medium size capacity range. The classification into ‘small’ and ‘medium’aligns with available chiller products; small applications are in this sense systemswith a nominal chilling capacity below 20 kW, and medium size systems mayrange up to approx. 100 kW.Systems in the small capacity range are usually consist of thermally driven chil-led water systems, whereas medium sized systems may be open cycle desiccantevaporative (DEC) cooling systems as well. While in the first type of system tech-nology the distribution medium is chilled water in a closed loop to remove theloads from the building, in the latter one supply air is directly handled in humi-dity and temperature respectively in an open process. Figure 2.1 visualises thetwo general types of applications. Of course, applications using both types oftechnology at the same time are possible. In chilled water systems, the centralcold water distribution grid may serve decentralised cooling units such as fancoils (mostly with dehumidification), chilled ceilings, walls or floors; but the chil-led water may be used for supply air cooling in a central air handling unit as well.The required chilled water temperature depends on this type of usage and isimportant for the system design and configuration, but the end-use devices arenot in the focus of SOLAIR and thus are not presented more in detail.Figure 2.2 illustrates that any thermally driven cooling process operates at threedifferent temperature levels: with driving heat Qheat supplied to the process at atemperature level of TH , heat is removed from the cold side thereby producingthe useful ‘cold’ Qcold at temperature TC. Both amounts of heat are to be rejected(Qreject) at a medium temperature level TM. The driving heat Qheat may be pro-vided by an appropriate designed solar thermal collector system, either alone orin combination with auxiliary heat sources.While in open cycle processes the heat rejection is with the air flow in the systemintegrated into the process, closed chilled water processes require for an externalheat rejection system, e.g., a cooling tower. The type of the heat rejectionsystem is currently turning more into the field of vision, as this component usu-ally is responsible for a considerable fraction of the remaining energy consump-tion of solar cooling systems.A basic number to quantify the thermal process quality is the coefficient of per-formance COP, defined as COP = Qcold / Qheat , thus indicating the amount ofrequired heat per unit ‘produced’ cold (more accurately: per unit removed heat).The COP and the chilling capacity depends strongly on the temperature levels ofTH, TC and TM. This dependency is discussed more in detail in e.g. [Henning,2006].In market available products of thermally driven chillers, the COP ranges at ratedoperation conditions from 0.5 to 0.8 in single-effect machines and up to 1.2 indouble-effect machines. 4
  6. 6. WP2 Preparation of a web based database of best available examples Best Practice CatalogueIn open cycle desiccant cooling systems, the COP is more difficult to assess,since it depends more strongly on the system operation. It is useful, to definehere the COP for the desiccant operation mode only, since in this operation modeheat is required. Experiences from DEC plants have shown that COP valuescomparatively to single-effect chillers may be achieved. ~18°C Chilled ceiling Heat > 60°C Supply air 16°C - 18°C Thermally (< 12°C) Fan coil driven Chiller Cooled / 6°C - 9°C Chilled water Conditioned temperature area Heat > 50°C Return air Supply air Desiccant evaporative Conditioned cooling (DEC) areaFigure 2.1 General types of thermally driven cooling and air-conditioning technologies.In the figure above, chilled water is produced in a closed loop for different decentralapplications or for supply air cooling. In the figure below, supply air is directly cooled anddehumidified in an open cycle process. Source: Fraunhofer ISE.The technologies are outlined more in detail below. Heat is required in both technologies,to allow a coninuous system operation. In the applications surveyed in SOLAIR, the heatis at least to a significant part produced by a solar thermal collector system. Qheat TH TM Qreject TC QcoldFigure 2.2 Basic scheme of a thermally driven cooling process. 5
  7. 7. WP2 Preparation of a web based database of best available examples Best Practice Catalogue2.1 Chilled water systemsAbsorption chillersThe dominating technology of thermally driven chillers is based on absorption.The basic physical process consists of at least two chemical components, one ofthem serving as refrigerant and the other as the sorbent. The main componentsof an absorption chiller are shown in figure 2.3. The process is well documented,e.g., in [ASHRAE, 1988]; thus, details will be not presented here.The majority of absorption chillers use water as refrigerant and liquid lithium-bromide as sorbent. Typical chilling capacities are in the range of several hun-dred kW. Mainly, they are supplied with waste heat, district heat or heat from co-generation. The required heat source temperature is usually above 85°C andtypical COP values are between 0.6 and 0.8. Until a few years ago, the smallestmachine available was a Japanese product with a chilling capacity of 35 kW.Double-effect machines with two generators require for higher driving tempe-ratures > 140°C, but show higher COP values of > 1.0. The smallest availablechiller of this type shows a capacity of approx. 170 kW. With respect to the highdriving temperatures, this technology demands in combination with solar thermalheat for concentrating collector systems. This is an option for climates with highfractions of direct irradiation. hot water (driving heat) cooling water GENERATOR CONDENSER ABSORBER EVAPORATOR cooling water chilled waterFigure 2.3 Scheme of a thermally driven absorption chiller. Compared to a conventionalelectrically driven compression chiller, the mechanical compression unit is replaced by a‘thermal compression’ unit with absorber and generator. The cooling effect is based onthe evaporation of the refrigerant (e.g., water) in the evaporator at low pressure. Due tothe properties of the phase change, high amounts of energy can be transferred. Thevaporised refrigerant is absorbed in the absorber, thereby diluting the refrigerant/sorbentsolution. Cooling is necessary, to run the absorption process efficient. The solution iscontinuousely pumped into the generator, where the regeneration of the solution isachieved by applying driving heat (e.g., hot water). The refrigerant leaving the generatorby this process condenses through the application of cooling water in the condenser andcirculates by means of an expansion valve again into the evaporator. 6
  8. 8. WP2 Preparation of a web based database of best available examples Best Practice CatalogueFigure 2.4a Examples of small absorption chillers using water as refrigerant andLithium-Bromide as sorption fluid. Left: air-cooled chiller with a capacity of 4.5 kW of theSpanish manufacturer Rotartica. Middle: 10 kW Chiller with high part-load efficiency andoverall high COP of the German manufacturer Sonnenklima. Right: Chiller with 15 kWcapacity, manufactured by the German company EAW; this machine is also available incapacities of 30 kW, 54 kW, 80 kW and above. Sources: Rotartica, Sonnenklima, EAW.Figure 2.4b Further examples of absorption chillers. Left: Ammonia-water Absorptionchiller with 12 kW chilling capacity of the Austrian company Pink. Middle: This chiller useswater as refrigerant and Lithium-Chloride as sorption material. The crystallisation phaseof the sorption material is also used, effecting in an internal energy storage. The capacityis approx. 10 kW; the machine is developed by ClimateWell, Sweden, and can operate asheat pump as well. Right: Absorption chiller with the working fluid H2O/LiBr and acapacity of 35 kW from Yazaki, Japan. This chiller is often found in solar cooling systems,since it was for several years the smallest in Europe available absorption chiller, appli-cable with solar heat. Currently, a smaller version with 17.5 kW chiller capacity from thismanufacturer has entered the European market. Sources: Pink, ClimateWell, Yazaki.Recently, the situation has changed due to a number of new chiller products inthe small and medium capacity range, which have entered the market. In ge-neral, they are designed to be operated with low driving temperatures and thus 7
  9. 9. WP2 Preparation of a web based database of best available examples Best Practice Catalogueapplicable for stationary solar thermal collectors. The lowest chiller capacity avai-lable is now 4.5 kW. Some examples of small and medium size absorptionchillers are given in figure 2.4. In addition to the traditional working fluidsH2O/LiBr, also H2O/LiCl and NH3/H2O are applied. The application of the latterworking fluid with Ammonia as refrigerant ist relatively new for building cooling,as this technology was dominantly used for industrial refrigeration purposes be-low 0°C in large capacities. An advantage of this chiller type is especially given inapplications, where a high temperature lift (TM – TC) is necessary. This is forexample the case in areas with water shortage, when dry cooling at high ambienttemperatures has to be applied.Adsorption chillersBeside processes using a liquid sorbent, also machines using solid sorption ma-terials are available. This material adsorbs the refrigerant, while it releases therefrigerant under heat input. A quasi-continuous operation requires for at leasttwo compartments with sorption material. Figure 2.5 shows the components ofan adsorption chilller. Market available systems use water as refrigerant andsilica gel as sorbent, but R&D on systems using zeolithes as sorption material isongoing. CONDENSER cooling water 2 1 cooling water hot water (driving heat) chilled water EVAPORATO RFigure 2.5 Scheme of an adsorption chiller. They consist basically of two sorbent com-partments 1 and 2, and the evaporator and condenser. While the sorbent in the firstcompartment is desorbing (removal of adsorbed water) using hot water from the externalheat source, e.g. the solar collector, the sorbent in the second compartment adsorbs therefrigerant vapour entering from the evaporator; this compartment has to be cooled inorder to increase the process efficiency. The refrigerant, condensed in the cooled con-denser and transferred into the evaporator, is vaporised under low pressure in the eva-porator. Here, the useful cooling is produced. Periodically, the sorbent compartment areswitched over in their functions from adsorption to desorption. This is usually donethrough a switch control of external located valves.To date, only few manufacturers from Japan, China and from Germany produceadsorption chillers; a German company is with a small unit of 5.5 kW capacity onthe market since 2007 and has increased the rated capacity in an improvedversion to 7.5 kW (model of 2008). Typical COP values of adsorption chillers are 8
  10. 10. WP2 Preparation of a web based database of best available examples Best Practice Catalogue0.5-0.6. An advantage of the chillers are the low driving temperatures, beginningfrom 60°C, the absence of a solution pump and a comparatively noiseless ope-ration. Figure 2.6 shows as an example two adsorption chillers.Figure 2.6 Examples of adsorption chillers. Left: Chiller with 70 kW capactiy of theJapanese manufacturer Nishiyodo. Adsorpition chillers of similar medium capacity areavailable from the Japanese manufacturer Mayekawa as well. Right: Small-size adsorp-tion chilller with approx. 7.5 kW capacity from SorTech company, Germany.An overview on closed cycle water chillers is given in [Mugnier et al., 2008]2.2 Open cycle processesWhile thermally driven chillers produce chilled water, which can be supplied toany type of air-conditioning equipment, open cooling cycles produce directlyconditioned air. Any type of thermally driven open cooling cycle is based on acombination of evaporative cooling with air dehumidification by a desiccant, i.e.,a hygroscopic material. Again, either liquid or solid materials can be employedfor this purpose. The standard cycle which is mostly applied today uses rotatingdesiccant wheels, equipped either with silica gel or lithium-chloride as sorptionmaterial. All required components are standard components and have been usedin air-conditioning and air-drying applications for buildings or factories sincemany years.The standard cycle using a desiccant wheel is shown in figure 2.7. The appli-cation of this cycle is limited to temperate climates, since the possible dehumidi-fication is not high enough to enable evaporative cooling of the supply air at con-ditions with far higher values of the humidity of ambient air. For climates likethose in the Mediterranean countries therefore other configurations of desiccantprocesses have to be used.Systems employing liquid sorption materials which have several advantages likehigher air dehumidifiation at the same driving temperature and the possibility ofhigh energy storage by means of concentrated hygrocopic solutions are note yetmarket available but they are close to market introduction; several demon- 9
  11. 11. WP2 Preparation of a web based database of best available examples Best Practice Cataloguestration projects are carried out in order to test applicability of this technologyfor solar assisted air conditioning. A possible general scheme of a liquid desiccantcooling system is shown in figure 2.8. ba ckup hea te r return air 7 12 11 10 9 8 cooling humidifie r loa ds 1 2 3 4 5 6 supply a ir de hum idifier hea t rec ove ry whee l wheelFigure 2.7 Scheme of a solar thermally driven solid Desiccant Evaporative Coolingsystem (DEC), using rotating sorption and heat recovery wheels (source: Fraunhofer ISE)and below: sketch of the DEC unit (source: Munters). The successive processes in the airstream are as follows:1 2 sorptive dehumidification of supply air; the process is almost adiabatic and the air is heated by the adsorption heat released in the matrix of the sorption wheel2 3 pre-cooling of the supply air in counter-flow to the return air from the building3 4 evaporative cooling of the supply air to the desired supply air humidity by means of a humidifier4 5 the heating coil is used only in the heating season for pre-heating of air5 6 small temperature increase, caused by the fan6 7 supply air temperature and humidity are increased by means of internal loads7 8 return air from the building is cooled using evaporative cooling close to the saturation line8 9 the return air is pre-heated in counter-flow to the supply air by means of a high efficient air-to-air heat exchanger, e.g. a heat recovery wheel9 10 regeneration heat is provided for instance by means of a solar thermal collector system10 11the water bound in the pores of the desiccant material of the dehumidifer wheel is desorbed by means of the hot air11 12exhaust air is blown to the environment by means of the return air fan. 10
  12. 12. WP2 Preparation of a web based database of best available examples Best Practice Catalogue Regenerator ⇐ QH driving heat LiCl/water regeneration air concentrated solution storage solution Absorber ⇒ QM rejected heat supply air diluted solutionFigure 2.8 General scheme of a liquid desiccant cooling system. The supply air isdehumidified in a special configured spray zone of the absorber, where a concentratedsalt solution is diluted by the humidity of the supply air. The process efficiency is increa-sed through heat rejection of the sorption heat, eg., by means of indirect evaporativecooling of the return air and heat recovery. A subsequent evaporative cooling of the sup-ply air may be applied, if necessary (heat recovery and evaporative cooling is not shownin the figure). In a regenerator, heat e.g. from a solar collector is applied, to concentratethe solution again. The concentrated and diluted solution may be stored in high energystorages, thus allowing a decoupling in time between cooling and regeneration to a cer-tain extent. Source: Fraunhofer ISE.In general, desiccant cooling systems are an interesting option if centralizedventilation systems are used. At sites with high latent and sensible cooling loads,the air-conditioning process can be splitted into dehumidification by means of athermally driven open cycle desiccant process, and an additional chilled watersystem to maintain the sensible loads by means of e.g. chilled ceilings with highchilled water temperatures, in order to increase the efficiency of the chilled waterproduction.More details on open cycle processes are given in [Henning, 2004/2008] and in[Beccali, 2008].2.3 Solar thermal collectorsA broad variety of solar thermal collectors is available and many of them areapplicable in solar cooling and air-conditioning systems. However, the appropri-ate type of the collector depends on the selected cooling technology and on thesite conditions, i.e., on the radiation availability. General types of stationary col-lectors are shown in figure 2.9. The use of cost-effictive solar air collectors in flatplate construction is limited to desiccant cooling systems, since this technologyrequires the lowest driving temperatures (starting from approx. 50°C) and allowsunder special conditions the operation without thermal storage. To operate ther-mally driven chillers with solar heat, at least flat plate collectors of high quality(selective coating, improved insulation, high stagnation safety) are to be applied.Not shown in the figure are concentrating and tracked collectors, which may beapplied to supply heat at a medium temperature level above 100°C and below 11
  13. 13. WP2 Preparation of a web based database of best available examples Best Practice Catalogue200°C in order to drive e.g. double-effect chillers or ammonia-water chillers for ahigh temperature lift. glas cover solar air collector insulation collector frame absorber with air channels glass cover flat plate collector insulation collector frame absorber with fluid channels glass cover CPC collector insulation reflector collector frame absorber with fluid channel evacuated tube collector evacuated evacuated tube glass tube optionally: reflector Absorber with fluid channel (forward/return)Figure 2.9 Examples of stationary collectors, applicable for solar cooling.Source: SOLAIR didactic material base / Fraunhofer ISE.3 SOLAIR database of solar cooling and air- conditioningWithin SOLAIR, data from successful running applications on solar cooling andair-conditioning in the small and medium cooling capacity range were collected.Table 3.1 summarises briefly the content of this database. More details are givenin the Cross-country analysis report of the database within SOLAIR [SOLAIR:Review technical solutions, 2008]. The Best Practice Examples, presented in thefollowing section, are extracted from this database. 12
  14. 14. WP2 Preparation of a web based database of best available examples Best Practice Catalogue Type of application Counts Technology Chilling Country in capacity database range [kW] Hospital (& retired people building) 1 Ab 10 FR Laboratory (for public hospital) 1 Ad 70 DE Public library 1 DEC 81 ES Public office 3 DECliq, DEC 11-30 DE, AT, PT Other public 2 Ad, DEC 5.5-6 DE, GR Commercial office 11 Ab 9-70 AT, FR, DE, GR, IT, PT, ES Commercial seminar area 1 DEC 60 DE Commercial wine storage 1 Ab 52 FR Residential 3 Ab, Ad 4.5-10 AT, IT, ES total: 24Table 3.1 Type of application, technology, cooling capacity and distribution by coun-try of the sytems in the SOLAIR data base.Abbreviations: Ab = Absorption; Ad = Adsorption; DEC = Desiccant Evaporative Cooling;DECliq = liquid desiccant cooling.4 SOLAIR Best Practice ExamplesMany of the Best Practice examples presented in the following went into ope-ration less than one or two years before the compilation of this catalogue, longterm operation experience can not be expected so far for this reason. Thus, thedefinition ‘Best Practice’ refers here to an appropriate system concept, successfuloperation and to advanced and promising approaches of solar cooling. The cata-logue aims to present the applicability of solar cooling technologies within diffe-rent building environments, at different locations and with different technicalsolutions.The examples are transferred into this catalogue according to their presentationat the SOLAIR web page. In some examples, more information is available in anadditional file, indicated right hand of the example and accessible for downloadfrom the web page. 13
  15. 15. WP2 Preparation of a web based database of best available examples Best Practice Catalogue4.1 Best Practice Examples: AUSTRIAExamples presented at the following pages: 1. Ökopark, Hartberg 2. Bachler, Gröbming 3. SOLution, Sattledt 14
  16. 16. WP2 Preparation of a web based database of best available examples Best Practice CatalogueTo be continued at the following page 15
  17. 17. WP2 Preparation of a web based database of best available examples Best Practice Catalogue View at the Ökopark Hartberg, Austria 16
  18. 18. WP2 Preparation of a web based database of best available examples Best Practice CatalogueTo be continued at the following page 17
  19. 19. WP2 Preparation of a web based database of best available examples Best Practice Catalogue Components of the Ammonia/Water chiller, installed at the Bachler system, Gröbming, Austria. Source: PINK Energie- und Speichertechnik. 18
  20. 20. WP2 Preparation of a web based database of best available examples Best Practice CatalogueTo be continued at the following page 19
  21. 21. WP2 Preparation of a web based database of best available examples Best Practice Catalogue Scheme of the solar cooling system at Sattledt, Austria 20
  22. 22. WP2 Preparation of a web based database of best available examples Best Practice Catalogue4.2 Best Practice Examples: FRANCEExamples presented at the following pages: 1. Résidence du Lac, Maclas 2. GICB building, Banyuls sur Mer 3. Kristal building, Saint Denis de la Réunion 21
  23. 23. WP2 Preparation of a web based database of best available examples Best Practice CatalogueTo be continued at the following page 22
  24. 24. WP2 Preparation of a web based database of best available examples Best Practice Catalogue Sc Scheme of the solar cooling system at Maclas, France 23
  25. 25. WP2 Preparation of a web based database of best available examples Best Practice CatalogueTo be continued at the following page 24
  26. 26. WP2 Preparation of a web based database of best available examples Best Practice Catalogue 25
  27. 27. WP2 Preparation of a web based database of best available examples Best Practice CatalogueTo be continued at the following page 26
  28. 28. WP2 Preparation of a web based database of best available examples Best Practice Catalogue Collector array and heat rejection unit of the Saint Denis de la Réunion solar cooling system, France 27
  29. 29. WP2 Preparation of a web based database of best available examples Best Practice Catalogue4.3 Best Practice Examples: GERMANYExamples presented at the following pages: 1. Fraunhofer ISE, Freiburg 2. University Hospital, Freiburg 3. Chamber of Commerce ‘Südlicher Oberrhein’ (IHK-SO), Freiburg 4. Office building of Ott Ingenieure, Langenau 5. Solar Info Center SIC, Freiburg 6. Office building of IBA AG, Fürth 28
  30. 30. WP2 Preparation of a web based database of best available examples Best Practice CatalogueTo be continued at the following page 29
  31. 31. WP2 Preparation of a web based database of best available examples Best Practice CatalogueSolar cooling system at Fraunhofer ISE in Freiburg, Germany. Top: cooling operation during summer. Bottom: heat pump operation during winter. 30
  32. 32. WP2 Preparation of a web based database of best available examples Best Practice CatalogueTo be continued at the following page 31
  33. 33. WP2 Preparation of a web based database of best available examples Best Practice Catalogue Vacuum tube collectors Local steam 81 m² network 90 m² Cooling Closed wet circuit cooling tower Solar heat storage Heating flap bypass Solar circuit circuit 2 1 2 3 Water / air heat exchanger flap storage Buffer storage ventilation system Heating circuit 1 A/C- Winter supply valve heating circuit Cold storage Adsorption chiller 70 kW Chilled water circuit Chilled water circuit secondary primary Scheme of the solar cooling system at the University hospital laboratory building, Freiburg, Germany 32
  34. 34. WP2 Preparation of a web based database of best available examples Best Practice CatalogueTo be continued at the following page 33
  35. 35. WP2 Preparation of a web based database of best available examples Best Practice CatalogueScheme of the Desiccant Evaporativ Cooling (DEC) system at IHK-SO, Freiburg, Germany 34
  36. 36. WP2 Preparation of a web based database of best available examples Best Practice CatalogueTo be continued at the following page 35
  37. 37. WP2 Preparation of a web based database of best available examples Best Practice Catalogue Heat production sub-system of the solar cooling system at Ott Ingenieure, Langenau, Germany 36
  38. 38. WP2 Preparation of a web based database of best available examples Best Practice Catalogue Cold production sub-system of the solar cooling system at Ott Ingenieure, Langenau, Germany 37
  39. 39. WP2 Preparation of a web based database of best available examples Best Practice Catalogue Solar Info Center SIC, Freiburg, GermanyTo be continued at the following page 38
  40. 40. WP2 Preparation of a web based database of best available examples Best Practice Catalogue Installed solar driven liquid desiccant evaporative cooling system and scheme of the system at the Solar Infor Center (SIC), Freiburg, Germany 39
  41. 41. WP2 Preparation of a web based database of best available examples Best Practice CatalogueTo be continued at the following page 40
  42. 42. WP2 Preparation of a web based database of best available examples Best Practice Catalogue Scheme of the solar cooling system at IBA AG, Fürth, Germany 41
  43. 43. WP2 Preparation of a web based database of best available examples Best Practice Catalogue4.4 Best Practice Examples: GREECEExamples presented at the following pages: 1. Center for Renewable Energy Sources, Koropi 2. Promitheus building – Sol Energy Offices, Palaio Faliro 42
  44. 44. WP2 Preparation of a web based database of best available examples Best Practice CatalogueTo be continued at the following page 43
  45. 45. WP2 Preparation of a web based database of best available examples Best Practice Catalogue Scheme of the solar driven desiccant evaporative cooling system at Lavrio/Koropi, Greece 44
  46. 46. WP2 Preparation of a web based database of best available examples Best Practice CatalogueTo be continued at the following page 45
  47. 47. WP2 Preparation of a web based database of best available examples Best Practice Catalogue Scheme of installations of the solar energy building in Palaio Faliro, Greece 46
  48. 48. WP2 Preparation of a web based database of best available examples Best Practice Catalogue4.5 Best Practice Examples: ITALYExamples presented at the following pages: 1. Manufacturing area, Bolzano 2. Residential building, Milan 3. ISI Pergine business center, Trento 47
  49. 49. WP2 Preparation of a web based database of best available examples Best Practice CatalogueTo be continued at the following page 48
  50. 50. WP2 Preparation of a web based database of best available examples Best Practice Catalogue Scheme of the solar cooling system in Bolzano, Italy. Top: cooling operation mode in summer; bottom: heating mode in winter 49
  51. 51. WP2 Preparation of a web based database of best available examples Best Practice Catalogue 50
  52. 52. WP2 Preparation of a web based database of best available examples Best Practice CatalogueTo be continued at the following page 51
  53. 53. WP2 Preparation of a web based database of best available examples Best Practice Catalogue Scheme of the cold production and cold distribution system at Trento, Italy 52
  54. 54. WP2 Preparation of a web based database of best available examples Best Practice Catalogue4.6 Best Practice Examples: PORTUGALExamples presented at the following pages: 1. INETI building, Lisbon 2. Office building Vajra, Loulé 53
  55. 55. WP2 Preparation of a web based database of best available examples Best Practice CatalogueTo be continued at the following page 54
  56. 56. WP2 Preparation of a web based database of best available examples Best Practice Catalogue Scheme of the desiccant evaporative cooling system (top) and of the solar / auxiliary heating sub-system (bottom) at the Ineti building, Lisbon, Portugal 55
  57. 57. WP2 Preparation of a web based database of best available examples Best Practice Catalogue 56
  58. 58. WP2 Preparation of a web based database of best available examples Best Practice Catalogue4.7 Best Practice Examples: SPAINExamples presented at the following pages: 1. Pompeu Fabra Library, Mataró 2. Headquarter building of CARTIF, Valladolid 57
  59. 59. WP2 Preparation of a web based database of best available examples Best Practice CatalogueTo be continued at the following page 58
  60. 60. WP2 Preparation of a web based database of best available examples Best Practice Catalogue Scheme of the desiccant evaporative cooling system (DEC) in the public library at Mataró, Spain 59
  61. 61. WP2 Preparation of a web based database of best available examples Best Practice CatalogueTo be continued at the following page 60
  62. 62. WP2 Preparation of a web based database of best available examples Best Practice Catalogue 61
  63. 63. WP2 Preparation of a web based database of best available examples Best Practice Catalogue5 Solar cooling: examples on advanced approachesThe majority of installed solar cooling systems use stationary solar thermal col-lectors, either of flat-plate type or evacuated tube collectors as shown in section2.3. These collectors are sufficient to provide driving heat for the type of coolingtechnologies as presented in the examples of section 4.However, there are reasons for the application of advanced cooling technologies,requiring for driving temperatures above 100 C, to maintain the chilling process.Some of the reasons are: - the irradiation conditions at the site are favourable, to allow the operation of high efficient thermally driven cooling processes, e.g., the application of a double-effect absorption chiller. The higher thermal coefficient of perfor- mance of values > 1.0 allows to decrease the solar thermal collector capa- city as well as to decrease the heat rejection system significantly. Driving heat has to be provided at temperature levels typically > 150°C; - the system is used in an industrial or commercial application and cold is required for process cooling at temperature levels below the typical levels for building air-conditioning (e.g., < 0°C). Then, thermally driven chillers with ammonia-water as working fluid pair can be applied, but requiring for higher driving temperatures than for building air-conditioning; - water consumption of the heat rejection system may be a critical point in some mediterranean areas; thus, only dry cooling can be applied, resulting in heat rejection temperatures above 40°C. Consequently, a high tempe- rature lift from chilled water temperature level to the heat rejection level has to be maintained. An appropriate technology in this case again is a thermally driven chiller with ammonia-water as working fluid, operated at driving temperatures > 100°C.The latter type of application is the subject of the ongoing project MEDISCO[MEDISCO, 2006], co-ordinated by the Politecnico di Milano and carried out withadditional European partners from Tunesia and Marocco. The project is supportedby the European Commission. In this project, two systems will be demonstratedusing linear concentrating collector technologies in combination with NH3/H20absorption chillers for process cooling of a winery in Tunesia and of a dairy inMarocco. The first system went into operation in April 2008.For the first reason mentioned above, a demonstration system was recently in-stalled at the University of Sevilla, Spain. A linear concentrating Fresnel collectoris installed at the roof of the Escuela Superior de Ingenieros (ESI) of the Facultyof Engineering. The aperture area of the collector is 352 m², the rated thermalcapacity is 176 kW. Figure 5.1 shows the construction principle of this collector,which was supplied by the company PSE, Germany: lines of primary mirrors areindividually single-axis tracked in order to focus the irradiation towards a statio-nary receiver, located in a support above the mirrors. The receiver is equippedwith a secondary reflector in order to minimize radiation losses. Advantages ofthis collector technology are the low wind-resistance and the a high surface co- 62
  64. 64. WP2 Preparation of a web based database of best available examples Best Practice Catalogueverage. Both allows for the installation at flat roof tops, e.g. on commercial orindustrial buildings.The collector provides pressurised hot water at a temperature of approx. 170°Cto the double-effect chiller with a rated chilling capacity of 174 kW in this appli-cation. This is currently the double-effect chiller with the smallest rated chillingcapacity, delivered by the manufacturer Broad, China. Heat rejection is done inthis installation with river water, runnng throgh an external heat exchanger, thusno cooling tower is applied.More information on this type of installations are given in [Zahler, 2008].Figure 5.1 The Fresnel collector at the University of Sevilla is the solar heat source forthe double-effect chiller. Top: the primary mirrors are moved off focus; a simple methodto avoid stagnation problems. Bottom: view at the collector primary mirrors. Right: thedouble-effect absorption chiller. Sources: AICIA, Seville (top and right), PSE, Germany(bottom) 63
  65. 65. WP2 Preparation of a web based database of best available examples Best Practice CatalogueReferences[Henning, 2006]Hans-Martin Henning: Solar cooling and air-conditioning – thermodynamic analysis andoverview about technical solutions. Proceedings of the EuroSun 2006, held in Glasgow,UK, 27-30 June, 2006.[ASHRAE, 1988]ASHRAE handbook (1988) Absorption Cooling, Heating and Refrigeration Equipment;Equipment Volume, Chapter 13.[Henning, 2004/2008]Hans-Martin Henning (Ed.): Solar-Assisted Air-Conditioning in Buildings – A Handbook forPlanners. Springer Wien/NewYork. 2nd revised edition 2008; ISBN 3211730958.[Mugnier et al., 2008]D. Mugnier, M. Hamdadi, A. Le Denn: Water Chillers – Closed Systems for Chilled WaterProduction (Small and Large Capacities). Proceedings of the International Seminar SolarAir-Conditioning – Experiences and Applications, held in Munich, Germany, June 11th,2008.[Beccali, 2008]Marco Beccali: Open Cycles – Solid- and Liquid-based Desiccant Systems. Proceedings ofthe International Seminar Solar Air-Conditioning – Experiences and Applications, held inMunich, Germany, June 11th, 2008.[SOLAIR: Review technical solutions, 2008].Task 2.1: Review of available technical solutions and successful running systems. CrossCountry Analysis. Public accessible report in SOLAIR.www.solair-project.eu[MEDISCO, 2006]Mediterranean food and agro industry applications of solar cooling technologies. Contract032559 (EU-INCO). Co-ordination: Politcnico di Milano, Italy. Duration: 01.10.2006 –30.09.2009. www.medisco.org[Zahler, 2008]Chr. Zahler, A. Häberle, F. Luginsland, M. Berger, S. Scherer: High Teperature Systemwith Fresnel Collector. Proceedings of the International Seminar Solar Air-Conditioning –Experiences and Applications, held in Munich, Germany, June 11th, 2008. 64
  66. 66. Supported byThe sole responsibility for the content of this publication lies with the authors.It does not necessarily reflect the opinion of the European Communities. TheEuropean Commission is not responsible for any use that may be made of theinformation contained therein.

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