https://alojaservicios.us.es/difuseditorial/Extra_content/orc_ps_24/orc_editorial_110.pdf

Abstract

Pumped Thermal Energy Storage (PTES) is a promising technology for the long-term storage of electrical energy by using thermal energy reservoirs. PTES can be mainly classified into system configuration employing Joule-Brayton cycles and systems using Rankine cycles. With respect to Rankine cycles, the coupling between a high-temperature heat pump with an ORC power system is attracting increasing interest. In this framework, an experimental Rankine PTES system based on the coupling between a kW-scale ORC system with a high temperature heat pump is going to be developed and commissioned. In this paper, the procedure followed for the design of such experimental facility is presented and discussed. Four main configurations are proposed and compared in terms of achievable system roundtrip efficiency and minimization of the exergy destruction rate. Results demonstrate that roundtrip efficiencies lower than 40% are reached with the use of out-of-shelf devices, while by a proper system configuration and the customized design of the heat engine and heat pump, roundtrip efficiencies higher than 60% can be achieved.