Thermochemical Energy Storage for Power Generation on Demand

Matching the power supply with demand is a key issue for the development of renewable energy sources: the intermittence of wind or solar power can be overcome by integrating an energy storage system. In comparison with sensible and latent heat storage, thermochemical heat storage has the advantages of both a high energy density, so that reaction products can be stored at ambient temperature for later reuse, and a flexibility of transportation when off-site use is required. An initial thermodynamic and kinetic screening of thermochemical reactions in the temperature range of about 600 to 1200 K is presented. Thermodynamics and kinetics are used to characterize the reactions through the equilibrium temperature, the heat of reaction, the reaction rates, and recovery work. These aspects were studied theoretically and experimentally. The analysis defines the essential design parameters and provides guidance for the important assessment criteria of new candidate reaction systems.