Operational performance of a novel heat pump coupled with mini-channel PV/T and thermal panel in low solar radiation

摘要： Here we describe a heat pump system coupled with novel PV/T and thermal panels for space heating in low solar radiation conditions. Existing solar indirect-expansion systems connect the solar panels and evaporator of the heat pump in parallel with the heat storage tank. For our system these three components are instead connected in series, which can stabilize the temperature at the inlet of the evaporator and decrease the inlet temperature of the solar panels, leading to improved energy efficiency and the production of much more thermal energy. The experimental results of this system show that the average electrical, thermal and overall efficiency of the PV/T panels are 15.9%, 33.4% and 49.3%, respectively. The average thermal efficiency of the thermal panels is 60.4%, the COP of heat pump is 4.7 and the room temperature is constantly over 18oC. Based on the experimental results, some improvements are analyzed. We conclude that this operating model can meet the requirement of space heating in low solar radiation environments.