Influence of Co₂ Conditioning Strategies on Thermochemical Energy Storage Performance in Solar Power Towers
Abstract
This work presents a dynamic and techno-economic analysis of a solar power tower plant integrated with a thermochemical energy storage system based on the calcium looping process and coupled with a supercritical CO₂ Brayton cycle. The study evaluates five alternative configurations of the CO₂ storage line, aiming to improve operational flexibility, reduce parasitic consumption, and enhance system efficiency. Dynamic simulations were performed in OpenModelica using real meteorological data from Carrera Pinto, Chile, with component models for compression, expansion, reheating, and hybrid thermal storage integration. The results demonstrate that the inclusion of molten salt and thermal oil subsystems significantly reduces auxiliary power demand and improves thermal management. Among all configurations, the thermal oil system achieved the best techno-economic performance, with a LCOE of 90.28 USD/MWh and a capacity factor of 65.1%. The findings confirm the potential of TCES-CaL integrated with sCO₂ Brayton cycles as a feasible pathway for next-generation dispatchable solar power plants.
Keywords
Calcium looping, supercritical CO₂ Brayton cycle, dynamic simulation, techno-economic analysis, renewable energy integration