Operation and performance of Brayton Pumped Thermal Energy Storage with additional latent storage

Pumped Thermal Energy Storage (PTES) is an increasingly attractive area of research due to its multidimensional advantages over other grid scale electricity storage technologies. This paper built a model and numerically studied the performance Argon based Brayton type PTES system. The was used optimise total work output round-trip efficiency aspect ratio thermal tanks operation packed bed segmentation have been varied assess their impacts on efficiency. Longer thinner were found increase efficiency, with hot tank length affecting system greater extent than cold tank. Larger ‘temperature ratio’ in develop higher exit working fluid temperature from shorter duration demonstrating better performance. Key features describing power identified as region maximum steepness ‘power front’. To maximise high decrease width front, additional latent heat used, effect which then assessed predicted efficiencies up 80% using isentropic reciprocating compressor/expander architecture, close theoretically limit.