Publisher: GIZ Chile with Chile Ministry of Energy; authored by DLR (Geyer, Trieb, Giuliano)
Date: August 25, 2020
Source title: Repurposing of existing coal‑fired power plants into Thermal Storage Plants for renewable power in Chile — Executive Summary
Intro-summary
This executive summary proposes converting Chile’s retiring coal plants into “Thermal Storage Plants” by replacing boilers with molten‑salt steam generators charged by renewable electricity via resistive heaters, reusing the Rankine cycle and interconnection. A Chilean 250 MW case shows best annual round‑trip efficiencies around ~38% with 12–14 h discharge and modeled levelized cost of discharge below ~90 USD/MWh under assumed 20 USD/MWh charging power, with capex dominated by storage and salt heaters.
System modeling of Chile’s long‑term energy plan (PELP) finds scenarios that add CSP with storage and convert coal sites to TSPs can maintain firm capacity post‑2040, reduce curtailment, lower specific system costs, and cut emissions versus baseline pathways without storage plants. Policy recommendations include enabling 14 h discharge windows and bankable storage energy/capacity offtakes to make projects financeable.