Evaluating the Effects of Building and HVAC Features on Solar Battery Degradation in Residential Building

Energy flexibility in buildings is essential for supporting energy systems with high renewable penetration. As building sector electrification accelerates, with photovoltaic (PV) plants powering heat pump-based HVAC systems, the proper management of the produced renewable energy is essential. Hence, energy storage systems are required to address the intermittent nature of renewable sources and the time mismatch between supply and demand. Battery Energy Storage Systems (BESS) are particularly versatile and can enhance the energy performance of buildings, improving self-consumption and self-sufficiency. However, their performance is not constant, but it decreases in time as a result of cyclic charging/discharging operations. The HVAC system ' s characteristics and control logic can affect battery degradation by modifying the charge and discharge cycles. This paper analyses the energy performance of a building coupled with an HVAC system supplied with a PV plant and a battery storage system. The building was modelled in TRNSYS considering the energy capacity degradation of the battery. Key performance indicators, such as self-consumption and self-sufficiency, were evaluated for different thermal insulation characteristics of the building and PV sizes. A sensitivity analysis was performed to assess the impact of plant characteristics on battery degradation. Results indicate the importance of proper HVAC sizing approaches to contain battery degradation and not alter the energy and economic benefit of its use.