Towards a low-carbon power grid: a prospective life cycle assessment of aqueous Zn//MnO2 battery energy storage with integrated power generation in China

Traditional thermal power generation (TPG) emits substantial greenhouse gases (GHG). As power systems transition to hybrid energy structures, generation integrated with energy storage (GIES), which combines multi-energy generation units with aqueous Zn//MnO2 battery storage to accommodate renewables and reduce curtailment, has become an important direction. However, the lifecycle GHG emissions of GIES have not been quantified. This study employs prospective life cycle assessment (pLCA) based on expected future battery performance and China's grid decarbonization scenarios to systematically compare the lifecycle GHG emissions of TPG and GIES. Life cycle inventory data are derived from laboratory scaling and literature, with system boundaries excluding battery transport and end-of-life disposal. Results show that under China's 2024 average grid mix, GIES reduces lifecycle GHG emissions by 34% per MWh delivered compared to average TPG. This advantage originates from renewable substitution and storage of curtailed power, with use-phase emissions dominating (87%). The emission reduction benefit amplifies dynamically as renewable penetration increases, reaching over 80% when GIES fully accommodates wind and solar curtailment. Sensitivity analysis further identifies battery round-trip efficiency as the most critical factor. This study preliminarily reveals the decarbonization potential of grid-scale aqueous zinc-ion batteries under specific assumptions and provides a framework for their sustainable development.