Nuclear Power Coupled With Thermal Energy Storage: Impact of Technical Performance on Economics in an Exemplary Electricity Grid

Abstract

Thermal energy storage (TES) coupled with nuclear energy could be a transformative contribution to address the mismatch in energy production and demand that occur with the expanding use of solar and wind energy. TES can generate new revenue for the nuclear plant and help decarbonize the electricity grid. Prior work by the authors identified two technical approaches to interface TES with nuclear. One, termed the primary cycle TES, charges and discharges the TES within the main Rankine power cycle. The second, termed the secondary cycle TES or SCTES, discharges the TES to a secondary power cycle. The present work analyzes the potential economic benefits of TES in an arbitrage market for a 1050 MWe nuclear plant. The study is the first to provide a realistic quantification of the impacts of changes in capacity factor due to use of TES on revenue and internal rate of return (IRR). The analysis is for a three-year period for peaking powers from 120% to 150% of the conventional nuclear plant for an exemplary deregulated utility represented by the Electric Reliability Council of Texas (ERCOT). The SCTES consistently provides the highest revenue and IRR. The benefits increase with increasing use of TES and variability of electricity prices. The results provide a technically sound understanding of the effects of how TES is integrated with nuclear power on economics and strong economic support for pursuing design and implementation of the SCTES.