Performance sensitivity of hot and cold thermal storage with onsite photovoltaics and heat pumps

Abstract

Heat pumps integrated with thermal storage can help in the electrification of buildings’ thermal loads while simultaneously providing flexibility to the electricity network. In this study, we investigate the energy performance of these electrified thermal systems when combined with onsite photovoltaics for a range of buildings with different thermal characteristics, orientations, occupancy profiles, and solar panel directions. This sensitivity analysis demonstrates the robustness of the potential benefits of these thermal systems when installed and operated under non-optimal conditions. The findings of this study reveal significant grid electricity savings achieved by these integrated systems, ranging from approximately 50% to 80% in both heating- and cooling-dominated regions with diverse climates, even under reasonable extreme conditions. These outcomes remain consistent regardless of variations in PV direction, house thermal performance, building orientation, and occupancy profile. By utilising thermal energy storage to store surplus solar energy, the system enhances the PV self-consumption ratio and solar fraction by approximately 30% irrespective of moderate deviations in PV direction.