Exergoeconomic analysis of a pumped heat electricity storage system based on a Joule/Brayton cycle

Abstract

Storing electrical energy in the form of thermal energy, pumped heat electricity storage (PHES) systems are a location-independent alternative to established storage technologies. Detailed analyses, considering the transient operation of PHES systems based on commercially available or state-of-the-art technology, are currently not publicly accessible. In this work, numerical models that enable a transient simulation of PHES systems are developed using the process simulation software EBSILON® Professional. A PHES system based on a Joule/Brayton cycle is designed, considering commercially available and state-of-the-art components. Employing the developed models and an exergoeconomic analysis, the transient operation of the PHES system is simulated and evaluated. The analyzed PHES system reaches a round-trip efficiency of 42.9%. The exergoeconomic analysis shows that PHES systems have higher power-specific costs than established storage technologies. They can currently not be economically operated at the day-ahead market for Germany and Austria, which is predominantly resulting from high purchased equipment costs. However, PHES systems have the advantage of being location-independent.