The GRE-GEO workshop series, which took place on September 18 at Celle Drilling 2024, was a complete success. Under the direction of Javier Holzmann from Clausthal University of Technology, around 40 participants came together to discuss the results and progress of the GRE-GEO project. The workshops formed the conclusion of the Celle Drilling event program and were among the highlights of the conference. In a total of four sessions, different topics related to the comparison of glass fiber reinforced epoxy (GRE) and steel in geothermal applications were discussed. In addition to the workshops, project partner Future Pipe Industries presented the project at its own GRE-GEO stand. In the first workshop, Ferid Seyidov (Vulcan Energy) gave a comprehensive overview of the origins, objectives and partners of the GRE-GEO project. He presented the newly developed GRE borehole design and the custom-made GRE handling tool from Drilltec. In addition, Seyidov explained the HAZID (Hazard Identification) analysis, which was specially developed for fiber-reinforced thermoplastic pipes (FRTP), and showed its importance for various project aspects such as wear resistance. He concluded by discussing new tools developed specifically for the testing and design requirements of the project. Stefan van der Sar (NRG) then compared steel and GRE-based geothermal systems in terms of conventional and radioactive deposits. He pointed out that the deposits on GRE adhere three to ten times less than on steel, which is mainly due to the lower hardness of the GRE material. This finding was integrated into a model developed in the project, which takes the entire geothermal pipe system into account. With this approach, the overall benefit of GRE in terms of deposition rates is slightly lower, but still significant. There is no difference in the radioactivity concentration (Becquerel per gram of deposit) between steel and GRE-based wells, but the total radioactivity (Becquerel) builds up more slowly with GRE. Leo de Mul (Dynaflow) presented the mechanical properties of GRE pipes under surface and underground conditions and presented the differences between GRE and steel in terms of load-bearing capacity, time-dependent material behavior and methods for determining performance. A key result was the development of an empirical-analytical prediction curve for the collapse pressure as a function of the pipe wall thickness (D/t ratio), which will serve as a basis for future research and further developments in underground applications. Javier Holzmann (TU Clausthal) showed how traditional steel standards can serve as a basis for new GRE standards, with a special focus on the API 5CT/5C3 and API 5C5 qualification tests for pipes and joints. He explained how experience from ISO 14692 for composite pipes can be combined with API standards to improve the design of laminates and joints for geothermal applications. Holzmann proposed a method to bridge the gap between these standards and increase the acceptance of GRE materials in geothermal applications. His presentation ended with an outlook on a key project goal that the GRE-GEO team is currently finalizing: a guideline for the design and qualification of composite pipes for low-enthalpy geothermal wells, specifically adapted to new operating conditions. As the GRE-GEO project funded by the GEOTHERMICA program draws to a close, this series of workshops has successfully showcased the project’s significant progress and contributions to the advancement of geothermal technology. The presentation materials will soon be available for download on the project website. We would like to thank all participants and visitors for their active participation and contribution to this successful event.

Networking, exchanging ideas, demonstrating expertise – as participants in the 7th Regional Conference on the Mobility Transition on June 4 in Wiesloch, we held interesting and valuable discussions at eye level with numerous political representatives, research institutions and companies from the Karlsruhe TechnologyRegion and the Rhine-Neckar metropolitan region. The approximately 500 participants at the regional conference in the Palatin Kongresshotel came from three German states – Baden-Württemberg, Hesse and Rhineland-Palatinate – as well as the French Collectivité européenne d’Alsace. The forward-looking event took place under the motto “Staying the course and mastering financial challenges” and was dedicated to climate-friendly mobility. In one of the numerous specialist forums on the topic of “Regional best practices for a sustainable mobility transition”, our Chief Technology Officer Dr. Stefan Brand spoke about sustainable lithium extraction in the Upper Rhine Graben and our project.

We are delighted that Vulcan will be represented at the 2023 Federal Garden Show in Mannheim as part of the Rhine-Neckar metropolitan region’s company presentations. We would like to invite you to attend our presentations in the MRN Pavilion in the experimental fields 77 and 78 and to take part in our discussions on the topics of resource efficiency, mobility and the energy transition. For quick access to the MRN Pavilion, we recommend using the parking bowl at Spinelli Quartier. We look forward to your participation in our presentations. If you require further information, please do not hesitate to contact us. Presentations at a glance: 30.09.2023 from 1pm to 1:20pm Energy transition: The challenges and prospects Managing Director Thorsten Weimann 22.07.2023 from 2:30 to 2:50 pm Mobility: The latest technologies and their environmental impact Dr. Horst Kreuter Managing Director and Founder 20.07.2023 from 2:00 to 2:20 pm Resource efficiency: Insights into current developments & discussion of opportunities Dr. Norbert Pralle

Vulcan Energie Ressourcen GmbH, headquartered in Karlsruhe, provided information on the results of the 3D seismic survey to date at a second participation workshop in Mannheim. The seismic in Mannheim was successfully completed in spring 2023. The workshop is intended to promote a transparent exchange between Vulcan and municipalities, associations, authorities and other stakeholders. As part of the workshop, the company informed around 40 participants about the results of the research to date. In various presentations, Vulcan reported on how the data was evaluated and how the location search can be derived from this. Based on this, the current project status and the further procedure, which includes the search for a location, were discussed. The possibilities of deep geothermal energy for municipal heating planning and CO2-neutral lithium extraction in the Upper Rhine Graben and possible timetables were also discussed. The information section was followed by a lively and interested exchange with the participants. Representatives of the affected municipalities, associations, authorities, companies and other stakeholders were given an insight into the progress of the project and were able to put their questions directly to the experts. The results of the data analysis so far promise a very large underground potential in the Mannheim area, more than previously expected, and further information and dialog events are planned. After all, the Vulcan project represents an important milestone on the road to climate neutrality in this region. A 3D seismic is a geological exploration. It is used by the company, which specializes in geothermal projects, to create a 3D model of the subsurface. The company is currently planning several geothermal projects in the Upper Rhine Graben region. With the help of geothermal energy, Vulcan will generate price-stable, safe and green energy for the citizens of the region and extract CO2-neutral lithium from the thermal water of the Upper Rhine Graben. The data collected during the seismic forms the basis for the projects in Mannheim.

On Tuesday, 28.03. we had the pleasure of welcoming Club60 from Mannheim-Vogelstang to the Insheim geothermal power plant. The 22 visitors were given a presentation on geothermal energy and lithium extraction, as well as electricity generation from the geothermal power plant. An interesting exchange was followed by a tour of the power plant with positive feedback.

We have been missing our geophones for a few weeks now: they are small, yellow and contain important data that can help to supply Mannheim with climate-neutral heat in the future. Information on their whereabouts not only helps to ensure a climate-neutral future, but also helps the European hamsters in Mannheim. For every geophone that is returned to us, we donate to the hamsters in Mannheim. We would be delighted to receive any relevant information about the location where we can collect the geophone. Have you seen anything? Then you can reach us at: E-mail: infobueroma@v-er.eu Phone: 0171 7908144 From 14.03. – 23.03.2023 posters about our geophone search can be found in the districts of Mannheim.

At the invitation of the CDU in Ladenburg, our regional managers Thomas Bening for the Kurpfalz and Hesse regions and Lucas Gehringer for the Ortenau region were able to present our geothermal project together with our Managing Director Dr. Horst Kreuter in the Domhofsaal in Ladenburg. The event was publicly advertised and, in addition to political representatives, the public was also invited via the local press. Here you can find the press release of the CDU Ladenburg.

On Friday, February 24, we completed the 3D seismic survey in Mannheim and the region. The underground survey was used to create a 3D model of the subsurface. The measurements were mainly carried out in the northern districts of Mannheim as well as in Ilvesheim, Ladenburg, Viernheim, Heddesheim, Edingen-Neckarhausen and Hirschberg an der Bergstraße. The measurements were carried out successfully and according to plan. This was also due to the very good cooperation and close coordination with the city of Mannheim: “Our thanks go in particular to Environmental Mayor Prof. Dr. Diana Pretzell and all the departments of the city of Mannheim involved,” says Vulcan founder Dr. Horst Kreuter. The Karlsruhe-based company was also always in close and trusting contact with the affected communities north of Mannheim. Vulcan also experienced great openness towards the measurements on the part of the citizens: “The discussions with the citizens were very constructive and we had the opportunity to explain the process in detail,” says Thomas Bening, Regional Manager for the Kurpfalz and southern Hesse. In the run-up to the event, Vulcan had already informed the public about the seismic survey through numerous measures – including information events, advertisements in official gazettes and other print media, radio spots, Facebook ads, roadshows, flyers about the seismic survey and information leaflets on geophones, press releases, press interviews and via the information office in Mannheim as well as the Natürlich Kurpfalz website, where Vulcan published the current measurement areas on a daily basis. The geophones were collected again. Experts then evaluated the data obtained. The data is used to plan geothermal projects that will help the city of Mannheim to become a climate-neutral EU model city by 2030. Vulcan also wants to use geothermal energy to produce CO2-neutral lithium for the local automotive industry. Initial analyses of the data are expected to be available in fall 2023.

On February 27, 2023, we welcomed the members of the Mannheim Environmental Forum to our geothermal power plant in Insheim. During a guided tour of the power plant, processes for the production of electricity and heat from deep geothermal water as well as lithium production for electric car batteries were presented.