What has been installed
The Danish geothermal company Green Therma has announced a demonstration of its Heat4Ever™ technology at the GFZ Helmholtz Centre for Geosciences research facility in Groß Schönebeck, Germany.
How the solution works
The patented Heat4Ever™ solution is a single-well closed-loop arrangement. It is intended to allow direct recovery of heat from underground hot water reservoirs without the use of heat pumps. An essential part of the arrangement is the vacuum-insulated DualVac™ well solution, which limits heat loss during transport from depth to the surface.
With the demonstration well installed, water circulates in the closed system, and geothermal heat is brought up from below 3 km depth at temperatures sufficient for direct use. Further tests in Groß Schönebeck are to supply data on long-term operation and stability of the system, as well as on heat recovery potential under different operating conditions.
Cooperation and the next project
The cooperation between Green Therma and GFZ, announced earlier this year, is an example of science and industry working together. The Groß Schönebeck research facility, located north of Berlin, provides both infrastructure and scientific support for testing new geothermal technologies under real underground conditions.
Green Therma has also already begun work on a full-scale project developed with Aalborg Forsyning in Aalborg, Denmark. It is to deliver geothermal heat to the local district heating network under a 30-year heat supply agreement. Drilling for that project is expected to start in early 2027.