Factor2 Energy, a German climate-tech company based in Duisburg, has successfully raised $9.1 million in seed funding to advance its innovative geothermal power generation system. The company uses carbon dioxide as the primary working fluid instead of traditional water or brine, potentially doubling power output under similar geological conditions.
At One Ventures led the funding round, with participation from High-Tech Gründerfonds (HTGF), Gründerfonds Ruhr, Verve Ventures, and Siemens Energy Ventures. The investment will fuel technological development and support the construction of a pilot power plant to demonstrate commercial scalability.
The global energy transition requires reliable, round-the-clock renewable power sources that can complement intermittent solar and wind generation. Geothermal energy offers this stability, but traditional systems face significant limitations in terms of suitable locations and economic viability.
"As a cornerstone for enabling broader electrification, the need for cost-effective baseload power has never been more urgent," said Helen Lin, Partner at At One Ventures. "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."
The seed capital will primarily support advancing Factor2 Energy's CO₂-based geothermal system toward commercial readiness. The company plans to build a pilot power plant that will demonstrate the technology's scalability and economic advantages over conventional geothermal approaches.
Beyond the pilot project, Factor2 Energy aims to expand into markets where traditional geothermal systems have proven uneconomical. The technology can access moderate-temperature resources at shallower depths, significantly reducing drilling costs and expanding the pool of viable power plant locations worldwide.
Factor2 Energy emerged from Siemens Energy, where co-founders Michael Wechsung, Joerg Strohschein, and CEO Felix Boehmer originally developed the technology. The team successfully completed a proof of concept before spinning out to form the independent company.
The startup's approach builds on decades of oil and gas industry expertise. "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 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."
Factor2 Energy's technology works by injecting CO₂ into deep, porous geological formations where it absorbs geothermal heat. The heated CO₂ naturally rises to the surface through the thermosiphon effect, eliminating the need for energy-intensive subsurface pumps. At the surface, the heat converts to electricity using a direct-driven CO₂ turbine system.
The company has attracted support from investors focused on climate solutions and energy transition technologies. Siemens Energy Ventures, which supported the technology's early development, continues to back the company's commercial efforts.
"I am pleased to see this technology progressing toward commercialization, following its development within Siemens Energy Ventures," stated Kendra Rauschenberger, General Partner at 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."
Timo Bertsch, Investment Manager at HTGF, highlighted the technology's potential to transform existing carbon storage infrastructure into active energy assets: "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."
