Integration of a PV system with an electric heat pump and an electric storage to increase self-consumption of an office building

A solar-based system meeting electricity, space heating and cooling demand of an office building located in southern Italy is here considered. The energy conversion system consists of a photovoltaic plant, an electric heat pump and an electric storage. Dynamic simulations to evaluate energy and environmental performance of this system, varying photovoltaic peak power (4.5-7.5 kW), battery capacity (3.2-9.6 kWh), and reference electric system are carried out. The proposed system is then compared to a reference conventional system based on the electric grid, a natural gas fired boiler and an electric chiller. The comparison is performed considering the reference electric efficiency of the Italian grid and its related CO2 emission factor available on monthly basis. The aim is to evaluate how the variation of electric reference efficiency can influence the energy and environmental performance of the solar-based system. The proposed system achieves interesting primary energy saving and reduction in terms of equivalent CO2 emission up to about 93%.