Electric energy storage based on thermomechanical concepts

The chapter provides an overview of the leading electric energy storage technologies based on thermodynamic concepts. In the introduction, the reasons that ignited the interest of researchers and stakeholders in these technologies are provided. Afterward, the technologies are introduced and analyzed. For each of them, the operating principles, the conventional configurations, and some advanced designs are described. The review focuses on the technology’s pros and cons by outlining any potential technological limitations. The technology performance is compared from the thermodynamic, technical, and economic perspectives to provide a comprehensive picture. Several performance indicators, such as round-trip efficiency, energy density, response time, operating lifetime, and cost are considered. Finally, a list of the currently operating plants and the existing prototypes is provided.