Model Validation and Performance Assessment of Unglazed Photovoltaic-Thermal Collectors with Heat Pump Systems
Abstract
PVT collectors convert solar radiation into both useful heat and electricity. Therefore, with the same PV area more solar energy could be harvested. The work investigates a novel unglazed liquid-based PVT collectors as a single source in a heat pump system for the energy supply of a single-family house. In this hybrid collector, the PV panel is thermally coupled with a specially designed brine-to-air heat exchanger on backside, which enables to gain energy from the sun and ambient air. Therefore, this novel collector is validated with the PVT collector model in TRNSYS for varying weather conditions based on the measurement results from our test facility and presented in the paper. The comparison shows good agreement, despite the missing reproduction of icing and detailed condensation processes in the simulation type. Based on this model, the impact of a PVT-heat pump system is further investigated by yearly dynamic simulations in TRNSYS for space heating, domestic hot water and defrosting of PVT. The results show that the seasonal performance factor of the PVT to HP system can reach 3.18 with the PVT area of only 20 m². The seasonal performance factor including self-consumed PV fraction for the heating system reaches 3.49 with the same collector area and without any additional battery storage.