Conceptual design of a pumped thermal energy storage system

Pumped thermal energy storage (PTES) is a concept for saving the excess electricity of the grid at off-peak hours and returning it back during peak time; This goal is achieved by performing two thermodynamic cycles, generally Brayton cycle and reverse Brayton cycle. In this paper, a PTES system is designed with an output power of ۲۶۰ MW. The designed system has a round-trip efficiency equal to ۵۰.۲%, and its operating temperature range is between ۲۰۱K to ۸۴۲K. The conceptual design procedure is done in four steps. In the first step, the system's configuration is determined. In the second step, the system’s model is implemented in Matlab R۲۰۱۸ to perform numerical calculations. In the third step, initial conditions required by the system's model to compute thermodynamic properties at each state are provided. Finally, optimal parameters are computed in the fourth step, and the effect of turbomachines efficiency, heat exchangers effectiveness, and ambient conditions on the system's overall performance are investigated.

کلیدواژه ها:

thermal energy storage ، thermodynamics ، electrical grid ، PTES