In recent years, the development of a heat storage technology that can store and utilize waste heat from factories and power plants is advancing. Thermal storage technology uses the conversion of internal energy in materials to collect, store, and release thermal energy, thereby achieving reasonable regulation of the relationship between supply and demand of thermal energy, and can reduce the consumption of fossil fuels and achieve energy conservation.

In the heat storage technology, a chemical heat storage material capable of storing heat for a long time and having a high heat storage density and capable of facilitating heat transfer has attracted attention. Recently, R&D personnel of Panasonic Corporation of Japan and scientists from the University of Tokyo have developed a long-term heat-storage material that absorbs heat energy at warm temperatures from 38°C (311 K) to 67°C (340 K).

The material is composed of scandium-substituted lambda-trititanium-pentoxide (λ-ScxTi3-xO5). λ-ScxTi3-xO5 not only accumulates heat energy from hot water but also could release the accumulated heat energy by the application of pressure. λ-ScxTi3-xO5 has the potential to accumulate heat energy of hot water generated in thermal and nuclear power plants and to recycle the accumulated heat energy on demand by applying external pressure. Furthermore, it may be used to recycle waste heat in industrial factories and automobiles.

References: Yoshitaka Nakamura, et al, Long-term heat-storage ceramics absorbing thermal energy from hot water, Sci. Adv. 2020, DOI: 10.1126/sciadv.aaz5264