The study proposes two TES schemes: D1 stores medium‑temperature heat to later warm feedwater, and D2 stores high‑temperature heat to later generate steam; both use live and reheat steam as heat sources and incorporate steam ejectors to utilize residual pressure. Models in Ebsilon and Matlab quantify charging/discharging thermodynamics and constraints, including boiler heat balance, turbine axial thrust, and safe steam flow; flexible operation reduces minimum plant load from 30% to about 17.7% (D1 17.71%, D2 17.83%).
Ejectors increase equivalent round‑trip efficiency by 1.60% (D1) and 2.43% (D2); D2 achieves the highest round‑trip efficiency at 46.69% among the proposed configurations. Results map flexibility potential over temperature ranges and show co‑benefits for efficiency when pressure recovery is included.
Mission relevance
Well‑engineered TES retrofits that leverage existing steam cycles and add pressure‑recovery ejectors provide a pragmatic path to cut coal unit minimums, absorb more renewables, and prepare sites for deeper clean repowering