Global energy demand is surging. In 2024, electricity use grew by 4.3 percent, the fastest pace ever outside post-recession rebounds. Record heat is driving cooling demand higher, EV adoption continues to rise, and data centers and AI infrastructure are expanding rapidly.
This creates a critical need for baseload, decarbonized energy, yet geothermal’s vast potential remains largely untapped. It could power a significant share of the global economy, but today supplies only 0.3% of electricity. Conventional geothermal works only in select locations with high absolute temperatures, and the high exploration risks and drilling costs needed to reach them limit cost-competitive deployment.
Factor2’s geothermal system, which uses supercritical CO₂ as its working fluid, was founded to tackle these challenges and fulfill the potential of geothermal energy.
Factor2’s geothermal system uses CO₂ as the working fluid, offering inherent thermodynamic advantages over conventional water-based systems. With a low critical point (31 °C, 7.4 MPa), CO₂ readily becomes supercritical at moderate depths. In this state, heating within the reservoir causes density drop of roughly a factor of two (hence, Factor2) compared to the injected CO2, while water shows only marginal change under the same conditions creating a strong pressure differential for CO2. This pressure drives buoyancy and natural circulation, known as the thermosiphon effect, which lifts CO₂ to the surface without subsurface pumps. The process cuts parasitic energy use and reduces mechanical complexity.
At the surface, the pressurized CO₂ flows directly through a turbine to generate electricity before being cooled and reinjected into the reservoir, creating a closed cycle that enables continuous power generation while maintaining long-term CO₂ storage. Lower viscosity further improves flow. Unlike water-based geothermal systems, which are temperature-driven and typically require reservoirs of 150–300 °C, Factor2’s process is pressure-driven and can operate in cooler reservoirs of ~70 °C. This capability allows for development at shallower depths of 1.5–5 km, expands the range of viable sites, and significantly reduces drilling costs.
Factor2’s CO₂ supply can be drawn from several sources. In natural gas processing, CO₂ is routinely separated from methane to meet pipeline specifications, producing a concentrated, ready-to-use stream. Additional supply can come from post-combustion carbon capture systems or naturally occurring CO₂ reservoirs. This sourcing flexibility supports integration with carbon capture, utilization, and storage infrastructure, combining reliable, clean baseload power generation with a pathway for permanent CO₂ storage.
Factor2’s supercritical CO₂ system can produce up to twice the net power of conventional water-based geothermal at the same depths. The advantage comes from four times greater mass flow, enabled by lower viscosity. This offsets CO₂’s lower heat capacity, allowing high power output even from cooler reservoirs.
Capital costs are lower due to shallower drilling requirements and simpler equipment design. Factor2’s geothermal CO₂ cycle eliminates subsurface pumps and complex heat exchangers, reducing mechanical complexity and cost. This results in an estimated 1.7x to 3.4x decrease in cap-ex compared to conventional geothermal.
The system also outperforms other next-generation approaches such as AGS and EGS, which require temperatures of 150-400°C and depths of 3–7 km for AGS and 3–10 km for EGS. Achieving these conditions demands deeper drilling, which drives cost, as drilling accounts for roughly half of total capital expenditure. Operating at 1.5–5 km avoids much of this expense and expands viable sites.
Factor2’s CO₂ based geothermal system can reach regions where conventional, AGS, and EGS cannot. For example, in the Northeast U.S., even at 8 km depths, reservoir temperatures often stay below 200 °C, making traditional geothermal uneconomic. Factor2’s pressure-driven supercritical CO₂ cycle works at lower temperatures and shallower depths, enabling cost-effective baseload power.
In the U.S. and Hungary alone, identified sites could add ~16 GW of capacity—roughly equivalent to the world’s total installed geothermal capacity. . At a 90% capacity factor, that’s ~127 TWh annually and ~50 million tons of CO₂ abatement.
This dependable baseload could also integrate 39 GW of wind or 60 GW of solar. By pairing with industrial CO₂ capture, Factor2 transforms CCS from a cost center into a profitable clean energy asset.
The company is a spin-out from Siemens Energy, where the team has been working on basic research since 2021. Since then, the company completed several feasibility studies and successfully completed a proof of concept alongside multinational oil and gas companies.
Factor2 Energy is led by Felix Boehmer, Michael Wechsung, and Joerg Strohschein who all worked together at Siemens Energy.
Felix Boehmer (CEO) has ten years at Siemens and holds an M.S. in Mechanical Engineering and an MBA. Michael Wechsung (CTO) brings 30 years in the power industry as a principal Siemens steam turbine expert with 117 patents, while Joerg Strohschein (CFO) has three decades in the power and O&G sectors, including serving as CFO of Siemens Energy joint venture with S Shanghai Electric, in China.
“As a cornerstone for enabling broader electrification, the need for cost-effective baseload power has never been more urgent. The fluid physics of supercritical 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 technoeconomics 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.”
— Helen Lin, Partner, At One Ventures
