Control concepts of a radiant wall working as thermal energy storage for peak load shifting of a heat pump coupled to a PV array

Photovoltaic panels (PV) coupled to a heat pump supplying heat to a radiant wall is a system with potential to reduce the imported energy from the grid for heating and cooling of buildings. The radiant wall works as a thermal storage system (TES) allowing storage of the PV output and, thus, peak load shifting. However, the management of these technologies is complex due to the dynamics of the system. This paper presents several control concepts with different purposes such as shifting energy use to off-peak periods, maximizing self-consumption of PV output, and minimization of imported energy from the grid. An experimentally validated numerical model from previous research was used to investigate and compare the different proposed control concepts. Results showed that charging the wall with solar energy resulted in higher overall energy use of the heat pump, while the imported grid energy was significantly reduced, thanks to self-consumption.