Life cycle assessment of concentrated solar power plants using a molten salt electric heater to increase thermal energy storage

This study evaluates the environmental and techno-economic performance of a 110 MW central tower Concentrating Solar Power (CSP) plant with molten salt Thermal Energy Storage (TES) under three configurations (6, 9, and 12 h of storage) and two operational scenarios: (i) integration of a molten salt electric heater (MSEH) powered by curtailed photovoltaic (PV) energy, and (ii) MSEH integration combined with expanded TES capacity to fully utilize surplus PV electricity. The work introduces a novel consequential-Life Cycle Assessment (LCA)-based framework to quantify the environmental effects of integrating curtailed PV into CSP TES. Using LCA, the study quantifies the impacts of the proposed configurations on four environmental impact categories: climate change, particulate matter, ozone depletion, and land use. The results show that enhancing the TES through MSEH integration improves plant dispatchability, increases annual electricity output by up to 6.2 %, reduces parasitic standby losses, and leads to better overall environmental performance. Among the configurations, the combined MSEH and expanded TES option achieved the best performance, reducing life-cycle burdens by up to 10 %. The Energy Payback Time remained below 1.25 years, while the Energy Return on Investment exceeded 20, confirming high system efficiency. Levelized Cost of Electricity (LCOE) analysis also indicates economic gains. Overall, the study demonstrates the potential of curtailed PV as a complementary resource for dispatchable CSP systems and provides insights applicable to future hybrid renewable designs in high-penetration solar regions. • Integration of curtailed PV electricity into CSP via MSEH • Consequential LCA shows GHG emissions decrease up to 8.8 % per kWh generated. • EROI >19 and EPBT <1.25 years confirm strong energetic performance. • Hybrid scenarios reduce LCOE by 4 % compared to reference configurations. • Results highlight hybrid CSP-PV potential for improved sustainability.