Life Cycle Assessment of an Aquifer Thermal Energy Storage System: Influence of design parameters and comparison with conventional systems

Abstract

This paper presents a Life Cycle Assessment (LCA) of a low-power capacity Aquifer Thermal Energy Storage (ATES) system supplying a building on Bordeaux INP’s university campus, powered by the French low-carbon electricity mix. It compares environmental impacts with alternative thermal energy supply solutions, analyzing various scenarios including design choices, construction methods, equipment lifespan, and failures.Results show that the operational phase contributes 60% to the total environmental impact, mainly from electricity consumption by the heat pump and pumping wells. The ATES operational phase has a climate change impact of 37 gCO2eq kWhth−1, lower than reported in existing literature, but borehole construction, particularly chromium steel production for the casing, poses environmental burdens. The comparative assessment of the different scenarios underlines the pivotal influence of energy delivery optimization, borehole casing material choice, and heat pump performance coefficient on LCA outcomes.Comparative analyses demonstrate that ATES outperforms conventional natural gas or biomass heating and vapor compressor chillers for cooling, but slightly trails air or ground-source heat pumps. Despite high construction phase impacts, mitigation occurs relatively quickly, except for human health concerns.The study underscores the potential of low-power ATES systems with low-carbon electricity to replace fossil fuel or biomass-based heating, reducing environmental footprints. The choice between ATES and other heat pumps depends on the electricity mix, performance factors, and delivered energy.