Solar-Assisted Heat Pump

Solar-Assisted Heat Hump concept, aka SAHP, consists of combining the heat pump technology with solar collectors to enhance the system performances (both electric and thermal): the heat recovered by solar modules supplies the heat duty of the HP evaporator. Moreover, using PV/T panels, the electricity produced by the solar field can be used to feed the HP, reducing or nullifying the machine consumptions and increasing the electricity self-consumption, the renewables penetration in residential scenarios and reducing the stress of the national grid.

Measurements of temperatures, mass flow rates and electrical productions and consumptions allows to evaluate the coefficient of performance of the SAHP in real environmental conditions and analyze the feasibility of the system also in the worst cases (e.g. cloudy days).

At the SolarTechLab, two prototypes of this innovative technology are installed:

  • The first one is based on a commercial heat pump made by Hidros® coupled with commercial PV/T panels from Eclipse® company. This system is now in operation and several experimental campaigns were carried out.
  • The second one was completely designed in the laboratory. Together with experimental measurements, detailed modeling is also carried out to optimize the system operation and its integration in different applications. The prototype can work in several assets:
  • The first one is based on the direct expansion concept: the PV/T field is the evaporator of the heat pump to increase the electrical production and the thermal performance of the system.
  • The second one is based of the integrated dual-source concept: the air is an intermediate fluid that transfers the heat from the solar-source to the refrigerant: the heated water exchanges the heat with the air (with a temperature increase) and then the air flow heats up the refrigerant flow.
PV/T tiles of a direct expansion SAHP prototype

Dual-source evaporator of the SAHP prototype

Coefficient of performance of a tested SAHP