This project aims to develop and validate, up to Technology Readiness Level 4 (TRL 4), a novel thermochemical energy storage technology capable of storing medium-temperature heat in the range of 250–400°C at competitive cost and with very high efficiency. In addition to heat storage, the technology can upgrade stored thermal energy to substantially higher temperatures, thereby enabling the use of medium-temperature heat to drive high-temperature, higher-efficiency power cycles, such as supercritical systems. Energy is stored in the form of reversible chemical bonds, making the solution particularly suitable for long-duration and seasonal storage applications in both power generation and heating sectors. The proposed concept offers several additional advantages that strengthen its commercial and technical potential: (i) strong cost-effectiveness relative to alternative storage technologies due to its anticipated long service life and simple design and operation; (ii) compatibility with multiple heat sources, including solar thermal collectors, industrial waste heat, and electricity, as well as integration with various power blocks through appropriate material selection; (iii) capability for continuous discharge with periodic charging, a key requirement for many thermal power cycles when properly sized and configured; (iv) scalability to several hundred MWh of storage capacity, with storage durations ranging from days to seasonal timescales and minimal thermal losses; (v) absence of significant environmental, toxicity, or human health concerns; and (vi) broad future application potential through further case-specific development. The consortium comprises nine partners from across the European Union, including three universities, one research center, two SMEs, two large industrial enterprises, and one NGO. This balanced partnership ensures the full range of expertise required for successful project execution, future commercialization, and effective collaboration across the value chain. The technology will be demonstrated in multiple system designs and integration scenarios at a 5 kW thermal capacity in the DLR laboratory.
