www.iea.orgRenewableEnergyEssentials:SolarHeatingandCoolingnSolarheatingandcoolingtechnologiesusethesunlighttoproducedirectlyusableheatforwaterandspaceheatingorindustrialprocesses,ortorunair-conditioningsystems.nGlobalsolarheatingandcooling(SHC)potentialcontinuestogrow.Thesolarthermalcollectorcapacityinoperationworldwideequalled171gigawattsthermal(GWth)correspondingto244millionsquaremetersattheendof2008.nChinaaloneaccountedformorethanhalfglobalcapacity,with101GWth.OthercountrieswithalargenumberofcollectorsinoperationaretheUnitedStates(unglazedcollectors),GermanyandTurkey.Withrespecttothecapacityinstalledper1000inhabitants,theleadingcountriesareCyprus(651kWth),Israel(499kWth)andAustria(273kWth).nSolarthermalenergyfordomestichotwaterpreparationiscommonallovertheworldwithsignificantmarketpenetrationinAustralia,China,Europe,Israel,TurkeyandBrazil.nSo-calledsolar“combi-systems”forcombinedhotwaterpreparationandspaceheatingshowarapidlygrowingmarketinEuropeancountries.InGermanyandAustria,thepredominantshareoftheannualinstalledcollectorareaisalreadyforcombi-systems.nLarge-scale(producing1MWormore)solarsystemsfordistrictheatingshowconsiderablegrowthratesintheScandinaviancountries,GermanyandAustria.nNewapplicationsforlowtemperatureprocessheat,air-conditioningandcooling,aswellasdesalination,arenowenteringthemarket.nLowtemperaturesolarcollectorsforwaterandspaceheatingareveryefficient.Hightemperaturesolarcollectorsforrefrigeration,industrialprocessheatandelectricitygeneration,requireimprovements.Heatstorage(bothseasonalandcompact)representsakeytechnologicalchallenge.MarketstatusTheglobalsolarthermalmarketenjoyedagrowthFigure1:AnnualnewlyinstalledcapacityofglazedRecenttrendsrateofabout15%in2007(downfrom20%intubecollectorsbyeconomicregion2006),thankstoasustainedgrowthof22%inSource:IEASHC2009thelargestworldmarket,China(seeFigure1.)Installedcapacity[MWth/a]Provisionalnumbersfor2008suggestthat200820000witnessedfurther42%growthintheChinese18000Chi