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

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(R) 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.

Automated summary

Pumped heat electricity storage (PHES) systems store electrical energy in the form of thermal energy, offering an alternative to established storage technologies. Numerical models were developed to simulate the transient operation of PHES systems, showing a round-trip efficiency of 42.9% but higher power-specific costs compared to traditional storage technologies. Despite being not economically viable for the day-ahead market in Germany and Austria, PHES systems have the advantage of being location-independent.