Introducing large amounts of electricity produced from variable renewable energy sources such as wind and solar decreases wholesale electricity price while increasing the volatility of the market. These conditions drive the need for peak-load power generation, while regulation requirements fuel the push for flexible power generation. The increase of variable renewable energy in the market share, along with falling natural gas prices, makes nuclear power plants less competitive.
Thermal storage is being considered to increase nuclear power plant revenue. Thermal storage increases the flexibility of the nuclear plant system without sacrificing its efficiency. There are multiple opportunities to increase nuclear power plant revenue, including increased capacity payments, arbitrage, and ancillary services.
An economic analysis was performed to investigate the revenue increase of the system with thermal storage. The investment cost was assessed, and net present value was evaluated for the considered scenarios. Two system designs were considered in the analysis: a thermal storage system using the existing power conversion infrastructure, and an integrated design with thermal storage fully incorporated into the reactor system design. The preliminary analysis showed that introducing a thermal storage system is profitable for some scenarios considered. Profitability depends significantly on storage size, output flexibility, share of variable renewable energy, and market characteristics.