September 19th, 2025 – Factor2 Energy, a German (Duisburg) company with a novel approach to geothermal energy, today announced the successful completion of its seed funding round, raising US$9.1 million in venture capital.
The round was led by At One Ventures, with additional investments from High-Tech Gründerfonds (HTGF), Gründerfonds Ruhr, Verve Ventures and Siemens Energy Ventures.
Factor2 Energy will use the seed funding to advance the technological development of its CO₂-based geothermal power generation system and to develop a pilot power plant to demonstrate scalability.
Factor2 Energy is led by Michael Wechsung, Joerg Strohschein and Felix Boehmer who all worked together at Siemens Energy. There they invented a new, economically superior method to harness geothermal energy by utilizing CO₂ as the primary working fluid in the geothermal cycle, replacing water or brine.
Kendra Rauschenberger, General Partner at Siemens Energy Ventures, stated, “I am pleased to see this technology progressing toward commercialization, following its development within Siemens Energy Ventures. Geothermal energy is a reliable and renewable power source, and we will work with Factor2 Energy to tailor our turbines to meet the specific needs of this emerging market.”
How it Works: Clean Energy from Stored CO₂ – Safe, Scalable, and Sustainable
The technology can be deployed at either natural CO₂ Reservoirs or at reservoirs designated for Carbon Capture and Storage. The (naturally occurring or captured) CO₂ is injected into deep, porous geological formations, where it is securely stored. As it absorbs geothermal heat from the surrounding rock, its density decreases, initiating a buoyancy-driven circulation known as the thermosiphon effect. As a result, the CO₂ rises naturally to the surface via production wells, eliminating the need for subsurface pumps and significantly reducing parasitic energy consumption and mechanical complexity.
At the surface, the heat is converted into electricity using a direct driven CO₂ turbine system. After expansion, the CO₂ is cooled, reinjected into the reservoir, creating a closed cycle that enables continuous power generation while maintaining long-term CO₂ storage.
Compared to conventional water-based geothermal systems, this approach can achieve up to twice the power output under similar geological conditions, while requiring lower capital expenditures (CAPEX).
"Our approach enables emission-free, efficient, and baseload-capable electricity production, which is ideal for traditional oil and gas companies looking to diversify their operating assets," said CEO and co-founder Felix Boehmer. "And in fact, the entire system leverages proven technologies from the oil and gas sector, with its long history of drilling and geologic expertise."
Siting Simplicity: More Location Options and Operational Ease
Besides delivering reliable, 24/7 green power, the use of CO₂ enables access to a broader range of geological sites, unlocking heat from locations unsuitable for conventional geothermal systems.
Using CO₂ allows Factor2 Energy to tap into shallower and cooler geothermal sites, reducing drilling costs and expanding the range of viable power plant locations. The system operates efficiently where conventional geothermal fails, offering competitive Levelized Cost of Electricity. It also eliminates the need for secondary fluids or complex binary systems, simplifying operations. And, by leveraging both geological formations designated for CO₂ storage (CCS) and natural CO₂ reservoirs, Factor2 Energy can transform these into active energy assets.
Helen Lin, Partner at At One Ventures comments: “As a cornerstone for enabling broader electrification, the need for cost-effective baseload power has never been more urgent. The fluid physics of CO₂ as a geothermal working fluid enables a 2x increase in power output while operating at the same depths/temperatures as conventional geothermal, translating to efficiencies in both capex and opex. These techno economics combine to form a favorable LCOE at sites that would previously have been economically unviable. We are excited to support Factor2 to bring this crucial technology to market to unlock the potential of geothermal as a more prevalent source of green baseload”
Timo Bertsch, Investment Manager at HTGF comments: "We invested in Factor2 Energy because their innovative technology dramatically expands global geothermal potential and uniquely enables the transformation of CCS sites into energy-generating power plants. Their successful proof of concept in a geologically complex environment demonstrates the robustness and scalability of their approach. We believe Factor2 Energy is well positioned to play a pivotal role in the global energy transition."
About Factor2 Energy
Factor2 Energy is a German climate-tech company developing CO₂-based geothermal power systems. By using carbon dioxide as the working fluid, the technology accesses moderate-temperature geothermal resources. Compared to conventional systems, the technology can deliver up to twice the power output, without fracking, ultra-deep drilling, or water-intensive processes. Founded by a former Siemens Energy team after a successful proof of concept, the company is backed by leading climate investors, with its latest round led by At One Ventures. Factor2 Energy's mission is to unlock scalable, clean, baseload geothermal power while supporting permanent carbon storage.
For more information, please contact:
Felix Boehmer
felix.boehmer@factor2-energy.com
www.factor2-energy.com
