The joint strategy document “”DEEP GEOTHERMAL ROADMAP FOR GERMANY – Policy, Business and Science Policy Recommendations for a Successful Thermal Transition” by researchers from the Fraunhofer Society and the Helmholtz Association is available for download.
“Achieving climate neutrality in the heating market is a huge challenge and requires a whole set of measures,” explains Prof. Rolf Bracke, Director of Fraunhofer IEG and co-editor of the current geothermal roadmap for Germany. “Market players such as energy suppliers, industrial companies, the housing sector, the financial sector, politics, administration, trainers and municipalities need new instruments for this implementation task complex.” The strategy document aims to provide all stakeholders with the necessary information on the supply of geothermal heat, the versatility of the heat market and the technological realization of the thermal transition. The aim is to provide recommendations for action in order to realize the potential of geothermal energy in terms of climate-neutral heat supply.
The roadmap identifies five recommendations for action to rapidly develop geothermal energy for the heating market in Germany:
- Parliament and local councils should formulate clear expansion goals and back them up with appropriate legislation and statutes, from the federal law on mines to the planning of the municipal territory. The CO2 avoidance costs of different technologies can serve as a guide value to create comparability and competition.
- Small and medium enterprises such as municipal utilities are active in the heating market and can only bear limited economic risks such as deep geothermal energy exploration. Therefore, financial instruments are necessary for intermunicipal risk equalization such as public insurance or working capital which participates financially in the projects. In addition, the federal government should increase federal funding for efficient heating networks to more than one billion euros and the federal states should set up a comprehensive program of geophysical exploration in order to reduce the risk of discovery for the municipalities.
- The few dozen deep geothermal systems in Germany must now grow into thousands. This requires business investments in key technologies to achieve large-scale industry standards. Key technologies are drilling methods, reservoir management, borehole water pumps, high-temperature heat pumps, large-scale heat storage, cross-municipal combined heat networks, and cross-sector system integration.
- The growth of the geothermal industry does not require energy imports, but leads to creation of national value and creation of regional jobs in technological development and production as well as in the construction and operation of factories. We can assume approx. 5 to 10 full-time equivalent jobs per MW of installed capacity. To train thousands of skilled workers, courses that complement the existing offerings of the chambers of crafts, industry and commerce are needed.
- Solving social challenges requires social acceptance. Municipal players therefore need more than just business management and facility engineering strategies. It is therefore necessary to involve all local interest groups on the path of territorial thermal transition with citizen energy models, municipal communication strategies and transparent projects.
The roadmap now presented deals with the contribution of geothermal energy to the thermal transition. The focus is on hydrothermal reservoirs, i.e. rocks containing thermal water at depths between 400 meters and 5,000 meters. Geothermal water can be pumped from deep wells at temperatures between 15 and 180 degrees Celsius. They are available independent of season and time of day and can be used in particular for municipal heat supply, district heating, housing and the supply of industrial process temperatures. The technology is mature and has been used in many European cities, such as Paris and Munich, for decades.
The heating sector represents 56% of national energy demand. Only 15% of the heat is regenerative. While hydrogen and biomass will primarily need to meet the high temperature needs of energy-intensive base industry in the future, solar thermal and geothermal options in particular are available for low temperature uses below 200 degrees Celsius. The advantages of geothermal energy lie in base load capacity and small footprint, even in cramped urban conditions.
According to roadmap estimates, hydrothermal geothermal energy (possibly combined with large heat pumps) as a heat source for district heating networks could cover around a quarter of Germany’s total heat needs, i.e. around 300 terawatt hours of annual work with 70 gigawatts of installed power capacity. In 2020, 42 plants nationwide supplied 359 megawatts of installed heat output and 45 megawatts of electrical output (2020). Public households and private companies will need to invest 2.0 to 2.5 billion euros per gigawatt of installed capacity over the next 10 years to build this geothermal production infrastructure and connect it to municipal heat distribution infrastructures. This makes it possible to achieve competitive heat production costs of less than 30 euros per megawatt hour.
The joint strategy paper by researchers from the Fraunhofer Society and the Helmholtz Association “ROADMAP DEEP GEOTHERMAL ENERGY FOR GERMANY Recommendations for action for politics, business and science for a successful thermal transition” can be found here.
The roadmap editorial team includes:
- Rolf Bracke, Fraunhofer Institute for Energy Infrastructure and Geothermal Energy (IEG),
- Ernst Huenges, Helmholtz Center Potsdam German Research Center for Geosciences (GFZ)
- Simona Regenspurg, Ingo Sass, Daniel Acksel, Helmholtz Center Potsdam German Research Center for Geosciences (GFZ)
- Haibing Shao, Karsten Rink, Uwe-Jens Görke, Olaf Kolditz, Helmholtz Center for Environmental Research (UFZ)
- Judith Bremer, Eva Schill, Thomas Kohl, Karlsruhe Institute of Technology (KIT)
- Marcus Budt, Fraunhofer Institute for Environmental, Safety and Energy Technologies (UMSICHT)
- Harald Will, Gunnar Grün, Fraunhofer Institute for Building Physics (IBP)
- Gregor Bussmann, Thomas Reinsch, Anja Hanßke, Florian Hahn, Matthias Utri, Dimitra Teza, Florian Amann, David Bruhn, Leo Thien, Clemens Schneider, Fraunhofer (IEG)