Fraunhofer-Gesellschaft
Fraunhofer-Gesellschaft

Geothermal systems: warmth from the earth

The heat energy stored in the earth’s crust can be used for heating, cooling and generating energy. Geothermal systems harness this natural source of heat inside the ground and represent a baseload-capable, carbon-neutral energy source. Certain substances (H2, CO2, natural gas) and forms of energy (heat, cold) can also be stored underground. Fraunhofer does research in the areas of exploration, development and technical connection to existing and future supply structures.

This sustainable energy source is practically unlimited, offers a reliable alternative to fossil fuels and is an option for supplying heat for municipal and industrial purposes. The heat transition will involve existing systems and structures first and foremost. This is true not only of housing but also − and especially − of non-residential commercial and industrial buildings. Customized geothermal development systems, building energy concepts and transformation plans for commerce and industry are the necessary building blocks of the heat transition.

 

 

Insights into Fraunhofer research

 

© Fraunhofer IEG

Innovative underground heat storage

To achieve climate neutrality, Fraunhofer researchers are pursuing an approach found nowhere else in the world that combines solar heat, heat pumps and the use of underground mine water to store heat. They show that decommissioned mines can be integrated into existing district heating networks with beneficial effects.

 

 

Energy concept with underground mine water

Fraunhofer researchers are harnessing the geothermal potential of underground mine water to build a grid-connected, energy-conserving “fifth-generation” heat and cold supply. It is Germany’s most advanced municipal heat and cold supply concept.

 

© Fraunhofer IEG

Geothermal systems in the smallest spaces

Directional drilling allows geothermal probes to also reach large heat reservoirs located underneath existing buildings — with minimal space requirements at the surface. The GeoStar concept shows how even existing buildings can use the ground below them for climate-neutral heating and cooling.

 

© D. Zocher / Fraunhofer IEG

Research facility for large heat pumps

The incorporation of renewable electricity into the heat supply means that large-scale heat pumps will play a central role in the energy transition. Fraunhofer IEG is home to Germany’s first publicly accessible research facility for large heat pumps.

 

© Gundula Krause

Process steam from deep geothermal energy

Manufacturing paper requires a lot of energy. A significant portion of the energy and heat needed for paper drying comes from fossil fuels. Fraunhofer has conducted research on the generation of the required process steam using renewable heat sourced from deep geothermal energy.