The primary goal of the project is on the one hand to check the suitability of the limestone of the Muschelkalk formation for geothermal use and on the other hand to develop a concept for the exploration, development and operation of a heat storage system with the help of field and laboratory studies as well as by modeling. Since there are already sufficiently deep wells at the location of the former Berlin natural gas storage facility in Berlin-Spandau, this offers the unique opportunity to test the target horizon hydraulically and to accompany these tests with thermal, microbial and chemical monitoring. The concepts developed as part of the project are to be comprehensively validated and the applicability and transferability of the findings to the surrounding area of ​​Berlin are to be demonstrated. The following goals are to be achieved in detail:

1. Quantification of the hydraulic and thermal properties of the target horizon (Muschelkalkformation).
2. The structural geological characterization of the horizon in combination with the determination of the thermal-hydraulic properties and existing drilling data.
3. Determination of the chemical-microbiological processes in the target horizon with which heat storage (temperature change and fluid flow) can be expected.
4. Long-term forecast of the thermal, hydraulic, chemical, microbiological processes that can be expected in a storage operation.

Based on the knowledge gained (1-4), a development concept is ultimately developed specifically for geothermal use and the associated processes. This should form the basis for the development of geothermal systems, which can also be transferred to other locations. In addition, a hydrothermal potential assessment of the Muschelkalk formation is carried out at the site.