Combined Photovoltaic-Thermal System with Phase Change Material Thermal Storage Tank for Decarbonising Domestic Buildings

Abstract

Utilizing solar energy to replace fossil fuels for residential energy supply offers a promising strategy for decarbonizing domestic buildings. This study designed a Photovoltaic-Thermal system assisted by a Heat Pump and integrated with a Phase Change Material thermal storage tank (PVT-PCM) for residential heating and hot water supply. To analyze the performance of the solar energy supply and storage system, a thermal consumption model of a conventional house was built and combined with the PVT-PCM system model on the TRNSYS software. When using a 61.75 m2 PVT panel and 1.35m3 PVT float tank, along with a 0.45 m3 DHW tank, the system can cover 96% of the conventional house's thermal load in January and December, and fully meet the house's thermal needs in other months, maintaining an average temperature of 18.8 °C. The integration of a 0.382 m3 PCM tank has a limited impact on the system's thermal supply performance. However, when the PCM can be fully charged and has a release rate of 63.8%, it can lead to an 18.8% increase in thermal supply, a 1.5% improvement in the heat pump's Coefficient of Performance (COP), and an energy density of the PCM tank that's 17.8% higher than that of the water tank.