A Stirling engine for thermal energy storage

Abstract

This paper presents the design, development and testing of a Stirling engine tailored for use in a modular dispatchable concentrated solar power (CSP) system, and currently under development by Azelio. Tests are performed to evaluate the engine and data from testing is used to validate the numerical models used for design and optimization. The completed tests prove that the Stirling engine can be successfully adapted for integration in systems with latent heat thermal storage. A further optimization of the working gas channel is discussed, and it is shown that significant improvements are possible, which is important for the lower maximum cycle temperatures seen in TES based systems. The improved engine will be instrumental in achieving competitive LCOE figures for a Stirling based small-scale dispatchable CSP system.