Paper No 104 – Experimental Analysis of a Hight Temperature Heat Pump Using Stored Heat from a Solar Thermal System – 13th IEA Heat Pump Conference, Jeju, Korea
Thermal storage systems use for district heating can improve their efficiency by decreasing their storage temperature and therefore minimizing heat losses and cost. A high temperature heat pump (HTHP) operating with heat source temperature between 30 °C to 50 °C can further optimize the performance of the system and deliver hot water above 70 °C at demand. In this study a HTHP that uses thermal energy produced by a solar thermal system and stored in a seasonal thermal storage has been developed, installed and experimentally investigated under real conditions. An additional challenge of the present work was to build the heat pump using off-the shelf components without further modifications. During two years of operation the water source temperatures measured were from 31 °C to 40 °C and the heating capacity resulted from 35 kW to 43.7 kW. The COP calculated resulted in values from 5.3 to 6 for pressure ratios between 2.3 to 2.8. The results demonstrated that HTHPs are an attractive approach to use low grade heat sources specially when produced by renewable energy sources.