Sorption storage tanks (thermochemical storage tanks) have an energy density 3-4 times higher than water storage tanks. In addition, long-term heat storage is possible with virtually no losses.

With the help of numerous technological innovations, the costs can be minimized to less than 27€/kWh storage capacity and the sorption storage system can be developed towards market maturity.

Waste heat sources or solar thermal energy can be used for storage.

This solution is relevant for single-family homes with solar thermal energy for generating hot water or for heating.