Thermal modeling of a subterranean battery energy storage system for residential and commercial buildings

Battery systems are now routinely deployed at residential and commercial buildings to manage solar photovoltaic generation and electricity demand peaks. The siting of the battery is an important consideration for safety, thermal management, and size (footprint; physical presence). Subterranean (underground) installations have yet to be considered in detail, although they offer benefits in terms of these three considerations. We develop a subterranean battery finite element analysis model to investigate the thermal behaviour and energy performance. The model is calibrated and verified by comparison to experimental testing. The model is then used to investigate performance of the battery while subject to a range of use case application signals, soil thermal conditions, geographic region (soil temperature), and battery geometry. The model can be used to identify the impact of climatic conditions, shape choices, and restrictions on cycling operations due to temperature limitations. • Deployment of battery energy storage systems in buildings has grown significantly. • Battery siting and placement is an important part of integrating battery systems. • Subterranean installations provides alternatives spaces for battery placement. • Subterranean battery finite element analysis model is developed. • The model is calibrated and verified by experimental tests.