The imbalance between the time of renewable generation and the time of heat demand currently represents the bottleneck for the energy turnaround. The storage capacities required for this balance exceed the currently available capacities many times over. Thermal energy storage systems are a key technology which, due to their flexibility, can fill this gap and increase the share of renewables in the future energy system in order to achieve the climate targets.
The group "thermal energy storage" offers solutions that can meet the special requirements of the future energy system in terms of flexibility, efficiency and costs. In order to be able to cover the broad requirements of the different applications, three different storage technologies are being researched. Large heat storage systems and borehole heat exchangers (up to 120 °C) represent a particularly cost-effective storage solution for balancing volatile renewables in district and local heating networks, while thermochemical storage systems (up to 300 °C) are particularly suitable for long-term storage in building applications but also for sector coupling due to their high compactness and low losses. In addition, AEE INTEC is working on chemical storage (up to 800 °C), which can contribute to a significant CO2 reduction of energy-intensive industrial and district heating applications due to its high compactness and high temperature level.