Dynamic Modeling and Simulation of Natrium Energy Island with Molten Salt Energy Storage

Abstract

The increasing installment of solar and wind renewable energy systems create a volatile energy demand to be met by electricity providers. A nuclear hybrid energy system is a nuclear reactor with energy storage that integrates into the grid with renewable energy sources. The Natrium design by TerraPower and GE Hitachi is a sodium fast reactor with molten salt energy storage. The Natrium design operates at steady state of 345 MW and can boost up to 500 MW for 5.5 hours. This study uses Dymola and the Modelica language to model the Natrium-based NHES. The dynamic system model is tested using hourly historical data form Texas (ERCOT) 2021 to show how renewables affect the electricity demand and how energy storage affects the Natrium system response to the demand. According to the results, while the available storage will allow the Natrium design to boost electricity production when the demand and electricity price is high making it more economically viable, the current molten salt storage is undersized for the ERCOT market.