Field tests of a novel solar-assisted dual source multifunctional heat pump

In this paper, we present the results of field study concerning a novel solar-assisted dual-source multifunctional heat pump, installed in a detached house in Milan. The system couples hybrid photovoltaic/thermal (PVT) panels with multifunctional and reversible heat pump. The proposed system is equipped with an “air source” evaporator and a “water source” evaporator, connected in series and operated alternatively, based on the ambient conditions and system parameters. The “air source” evaporator is an external unit; conversely, the “water source” evaporator is connected with a storage tank, fed by the PVT system. The PVT system is connected with the heat pump by two storage tanks to be used to produce domestic hot water and to be used in “water source” evaporator. Based on the operating conditions, the hot water is sent to one of the storage tank. The proposed system has been tested experimentally; the results show that the system was able to maintain high efficiency in the different seasons and was able to produce domestic hot water. It was found that the use of the “water source” evaporator was able to compensate the performance degradation of the “air source” source evaporator caused by the low ambient temperature.