Thermal energy storage and the energy transition: MLU coordinates Europe-wide research project

An international research project led by the Martin Luther University Halle-Wittenberg (MLU) delves into the next generation of seasonal thermal energy storage systems. The "INTERSTORES" project is investigating optimal ways to construct new types of storage systems and integrate them into energy systems. The collaboration between science and industry will receive nearly eleven million euros as part of "Horizon Europe", with around 1.5 million euros going to MLU. The aim is to improve the utilisation and performance of heat storage systems, reduce production costs, and help the technology reach market maturity.

Feb 9, 2024, 10:44:43 AM
Tom Leonhardt, Martin-Luther-Universität Halle-Wittenberg

One major challenge with renewable energy is the ability to store it over a longer time. While regions with a temperate climate have a surplus of energy - especially heat - in the summer, it is in short supply during colder months. "That is why we need simple and cost-effective solutions so that, for example, the surplus energy from the summer can be used in the winter," explains Professor Peter Bayer, a geoscientist at MLU who is leading the project. The first heat storage systems are already up and running. In one technology type, water is heated using solar energy or waste heat from buildings and industrial plants and stored in large underground tanks. Ideally, there is enough stored energy to last into the winter when it can be utilised for heating. However, such large-scale thermal energy storage systems are still few and far between. "There are several barriers to tackle, including high investment costs, associated economic risks, and a lack of practical tools for planning and integrating these systems into local heating networks," says Bayer. "INTERSTORES" aims to systematically address these issues. The team is made up of partners from nine different countries. They specialise in business, engineering, geosciences, and environmental technology. The project strives to demonstrate how large storage systems can be built in a particularly efficient, cost-effective, and environmentally friendly way. The team is investigating two different facilities that will be constructed during the project period. One new plant is being built in a former basin infrastructure in Ingolstadt Germany. At the same time, a huge cavern, which will hold around one million cubic meters of water, is being excavated out of solid rock near Helsinki, Finland. "By including these two demonstration plants in the project, we have the unique opportunity to investigate the technology at full scale. We want to close critical knowledge gaps to create reliable, functionally robust systems and to obtain practical information for specific implementation projects in the future," concludes Bayer. Further information about the project can be found at