Paper No 178 – Dynamic performance tests of a heat pump cycle integrated latent heat thermal energy storage for optimized DHW generation – 13th IEA Heat Pump Conference, Jeju, Korea
Latent heat thermal energy storage (LHTES) bears the advantage of high energy storage density and balancing demand and supply. A promising application for residential buildings is the use of a compression heat pump (HP) in combination with a LHTES to generate domestic hot water (DHW) with the aid of the hot refrigerant compressor discharge. In this case the LHTES enables load shifting, heat pump operation harmonization and results in energy efficiency improvement. The setup investigated here is built of a compact combination of an air/water compression HP with R32 as refrigerant and a novel 3-media – Refrigerant, Phase Change Material (PCM) and Water – Heat EXchanger (RPW-HEX) which is directly integrated into the HP cycle between compressor and condenser. A key challenge of this combination is the dynamic system operation and control which is experimentally examined in this work. RPW-HEX charging and discharging as well as continuous operation is analyzed based on several weeks of operation. In this work it is proven that the proposed combination is capable to operate stable over a wide operating range and to generate DHW effectively.