Optimal Operation Strategies for Thermal Energy Storage Systems in Solar Thermal Power Plants

This paper examines the economic benefits of various operation strategies for a thermal energy storage (TES) system in a solar thermal power plant. A thermodynamic model developed to evaluate different design options has been utilized to calculate system performance and assess the impact of operation strategies, storage capacity, and market prices on the value of TES. The overall performance is also investigated through several parametric studies, such as solar multiple, geographic location, and choice of HTF. The influence of these parameters has been evaluated in consideration of exergy destruction due to heat transfer and pressure drop. By incorporating exergy-based optimization alongside traditional energy analyses, the results of this study evaluate the optimal values for key parameters in the design and operation of TES systems, as well as highlight opportunities to minimize thermodynamic losses. Annual performance for each case is characterized both by nominal and part-load efficiency. Levelized cost of electricity (LCOE) is calculated for all cases, illustrating a set of optimal parameters that yield a minimum LCOE value.Copyright © 2015 by ASME