Solar Thermal and Heat Pump Heating Technology for the Future?!

During the past years an increasing number of heating systems for domestic hot water preparation and space heating appeared on the European market, which combine solar thermal components with heat pumps. As result of the combination of these technologies, theoretically the thermal efficiency of both, the solar thermal components and the heat pump may be increased, due to several synergetic effects. This can lead to higher system performances. The technical realisation of the system combination can be done in various ways, which is reflected in the great diversity of concepts available on the market. To allow for differentiation of these system concepts, several classification schemes have been developed. These as well as selected system concepts are presented. However, up to now uniform and objective criteria for the assessment of the solar and heat pump systems' thermal performance are not yet available. For this purpose, new testing procedures are being developed at ITW and other institutions. The activities related to this include performance tests in the laboratory and in situ, as well as corresponding simulations and the definition of system performance factors. Activities in this field are concentrated in the lEA SHC Task 44 /Annex 38 "Solar and Heat Pump Systems" (joint Task of the Solar Heating and Cooling Programme and Annex of the Heat Pump Programme of the International Energy Agency). The most important performance test procedures and first results from field tests are presented.