The integration of water-to-air thermoelectric heat pumps with seasonal solar energy storage is proposed as a sustainable and energy-efficient avenue for supplying residential heat. Durham University, U.K., researchers contend that such an arrangement can compensate for the seasonal mismatch related to the thermal power eventually produced by both photovoltaic-thermal and solar thermal systems.

Such heat pumps can be powered by photovoltaic panels directly, offering silent operation and high reliability due to the absence of moving parts. To demonstrate the feasibility of this approach, a DC-powered experimental system was designed with a thermoelectric heat pump unit, a heat storage tank, a testing box and a data logger system. The heat pump tested included an aluminum-finned heat sink at the hot side of the module and a water-cooled plate at the cold side.

Heat transfer was enhanced by placing a high thermal conductance paste at the two sides of the thermoelectric module to reduce the contact thermal resistances. A cross-flow fan on the heat sink side served to enhance the heat exchange between the airflow and the heat sink, and a pumped water circulation loop connected the heat storage tank with the water-cooled plate.

The inclusion of the storage tank increased system heat output by 3° C compared to a heat pump without a tank. The coefficient of performance was also higher for this design relative to that without heat storage. The time required to heat the testing box was reduced by 18 m, which translates to a rapid achievement of the desired temperature.

The next step will entail testing the system configuration in a real building under climatic conditions in the U.K.

The research is published in the journal Energies.