Rodatherm Energy, a recently launched geothermal company, exited stealth mode on Monday, securing $38 million in investments and announcing intentions to construct a demonstration facility in Utah.
Unlike most enhanced geothermal firms that use water to extract heat from deep underground, this startup sets itself apart by running a closed loop—likely crafted from steel—through its boreholes, which circulates a refrigerant instead.
Evok Innovations led the Series A funding round, with contributions from Active Impact Investments, Giga Investments, Grantham Foundation for the Protection of the Environment, MCJ, TDK Ventures, Tech Energy Ventures, and Toyota Ventures.
Rodatherm faces strong competition from established companies in the sector, such as Fervo Energy, Sage Geosystems, XGS Energy, and Quaise.
Fervo is widely regarded as the industry leader, having raised close to $1 billion. The company is preparing to finish the initial 100-megawatt stage of its Cape Station facility next year, with an additional 400 megawatts expected to come online in 2028. Fervo has also agreed to provide Google with power for its data centers. Similarly, XGS Energy has struck an agreement with Meta to build a 150-megawatt power station in New Mexico to supply energy to Meta's data centers.
According to Rodatherm, its refrigerant-based closed-loop system achieves 50% greater efficiency compared to standard water-based geothermal setups. Air-source heat pumps, or minisplits, utilize hydrocarbon refrigerants to move heat between indoor and outdoor spaces.
The startup’s patent claims that its closed-loop configuration eliminates the need for filters that would otherwise be required in open-loop systems to prevent rock fragments and debris from entering as water loosens material underground. The design is also expected to significantly reduce water consumption.
However, Rodatherm’s method is likely to involve higher drilling and installation expenses compared to more straightforward alternatives. The company believes that the added efficiency from its refrigerant-based system could counterbalance these costs, but this will only be clear after a full-scale well is built.
With the Series A capital, the company aims to finish a small-scale 1.8-megawatt demonstration plant in Utah by late 2026. Utah Associated Municipal Power Systems is set to purchase electricity generated by this project.
