Heat engine-based storage systems

Abstract This chapter focuses on the use of heat engine-based storage systems. These cycles typically employ combinations of hot, cold, and chemical (fuel) energy storage. It starts with a thermodynamic review of typical heat engine cycles employed including Carnot, Rankine, and Brayton cycles. The definition of round-trip efficiency is presented. Four different storage techniques discussed include cryogenic, pumped heat, hydrogen, and compressed air energy storage. The relative merits of each will be discussed along with estimates for round-trip efficiency. While these cycles make use of thermal and chemical stores, these components will be discussed in other chapters.