In order to decarbonize the heat supply within the industry sector not only in summer but also in winter, long-term energy storage options are needed. Low capital cost and high energy storage density are of particular importance in this case. Therefore, Thermal Energy Storage (TES) and sector coupling Power-to-X-to-Heat technologies using "renewable fuels" are considered the most relevant technologies.
In focus are two storage options that are able to deliver heat directly at the required temperature: high-temperature (geothermal or very large scale) TES and chemical (Power-to-X) storage. Additionally, low-temperature TES, which are used to increase the source temperature of a heat pump and thus reduce the electric energy demand at the time of use, are also considered.
