Dynamic modelling of flexible dispatch in a novel nuclear-solar integrated energy system with thermal energy storage

Integrated energy systems can improve flexibility on future energy grids with one option being Nuclear-Solar hybrid systems. Integrating solar generated heat from parabolic troughs into the feedwater line allows the plant to alleviate turbine bled steam and transiently power boost 15% above nominal power for a nominal small modular PWR cycle. This article presents a parametric study of the design of such a system and provides a full system dynamic model written in the Modelica language to analyse the dispatch in transient load following operation. The control of the system is presented, and the transient analysis is shown to help inform sizing of the concrete storage and parabolic trough arrays. The trade off in design between improved degrees of power boosting and system nominal efficiency is investigated with the work suggesting that higher steam generator entry temperatures offer improved opportunities of up to 42% for power boosting flexibility.