fresh funding

Houston cleantech startup closes $17M round to tap into hot geothermal sector

The company develops ultra-high-temperature tools to withstand the heat of geothermal reservoirs. Photo via hephaeet.com

Houston-area startup Hephae Energy Technology Corp. has closed a $17.8 million Series A financing round to commercialize its geothermal technology.

The round was co-led by Pennsylvania-based Susquehanna Sustainable Investments, which invests in early-stage climatech companies, and Copenhagen-based Underground Ventures, which focuses on geothermal energy startups. Alfa8, Baruch Future Ventures, Centaurus Capital LP, Elemental Impact, Exa Ventures, Future Ventures, Grantham Foundation for the Protection of the Environment, New System Ventures and True North Institute joined the round, along with existing Houston-based investor Nabors Industries. Hyphae reports in a news release that the Series A round brings the company's total capital raised to $24.7 million.

Hephae develops ultra-high-temperature downhole sensing, measurement, communications and control systems that can withstand the heat of geothermal sites, which are hotter and deeper than traditional oil and gas reservoirs. The company's Pandora210 system can operate at up to 400 degrees Fahrenheit.

Hephae reports that it plans to use the new funding to commercialize its Pandora210 tool and to launch research and development into systems that can withstand temperatures of up to 570 degrees Fahrenheit. Houston-based Fervo Energy, for instance, recently tapped its hottest geothermal well to date in western Utah, showing temperatures above 555 degrees Fahrenheit.

"Commercial deployment represents a major milestone in our mission to scalable, always-on, emission-free power globally, with a world-class team to tackle this problem," Steve Krase, CEO of Hephae Energy Technology, said in the release." This investment enables Hephae to transition from development to scale, delivering the ultra-high temperature drilling technologies needed to support the rapid growth of the geothermal industry in the US and international markets."

Hephae has been collaborating with Fervo Energy in the field. The company told the Houston Business JournalHouston Business Journal this spring that it expected its Pandora210 technology to be deployed at its Utah sites.

“Fervo is encouraged by the early progress of our collaboration with Hephae, whose novel high-temperature innovations have the potential to contribute positively to EGS economics, unlock higher-energy geothermal resources, and further cement the competitiveness of next-generation geothermal power," Elliot Howard, director of drilling and completions at Fervo, added in the release.

As the geothermal industry continues to scale, Hephae says it aims for its technology to help companies "unlock hotter, deeper resources that result in lower produced energy costs."

The Spring-based startup was founded in 2020 by CEO Steve Krase and CTO John Clegg. Krase previously launched Navigate Energy Services, which was acquired by Nabors in 2013. Clegg is also an industry veteran and has held numerous leadership positions at energy companies, including Weatherford, NOV, Schlumberger and others.

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A View From HETI

Chevron is among the best places to work in the U.S. Photo courtesy of Chevron

A new U.S. News & World Report ranking of the best employers has named two dozen Houston-based companies among the best companies to work in the South, and more than half are part of the region's booming energy sector.

U.S. News' prestigious "2026-2027 Best Companies to Work For" ratings examine 3,900 public and privately owned companies across 14 industries to help employees and job seekers make decisions about workplaces that may be a good fit.

Each company is rated on a scale of 1-5 across six metrics: quality of pay and benefits; work-life balance and flexibility; job and company stability; physical and psychological comfort; belongingness and esteem; and career opportunities and professional development.

"Job seekers' definitions of 'best' evolve with their needs," said Carly Chase, vice president of Careers at U.S. News. "From new grads in the AI era and seasoned pros seeking a career change, to HR leaders researching organizational trends, the ratings are a central hub that highlights businesses that U.S. News found effectively support their staff."

The number of employers headquartered in the Houston area that made the cut for 2026-2027 has skyrocketed over previous years. A total of 24 local public and private companies made the list this year, up from 16 companies in 2024 and 11 in 2025.

The highest concentration of top employers is located in Houston proper (20), followed by two companies in The Woodlands and one each in Kingwood and Spring.

Several leading Houston energy powerhouses on the list include petroleum corporation Occidental (Oxy) and oil and gas giants Chevron and Phillips 66.

Other energy sector companies on the list are:

  • EOG Resources, Houston
  • Targa Resources, Houston
  • TechnipFMC, Houston
  • Cheniere, Houston
  • Baker Hughes, Houston
  • KBR, Houston
  • CenterPoint Energy, Houston
  • Powell Industries
  • S&B, Houston
  • DXP, Houston
Here are the remaining best Houston-based companies to work for:
  • David Weekley Homes
  • Comfort Systems USA, Houston
  • Corebridge, Houston
  • Cornerstone Home Lending, Houston
  • Farouk, Houston
  • Hines, Houston
  • Insperity, Kingwood
  • HPE, Spring
  • Sterling Infrastructure, The Woodlands
  • LGI Homes, The Woodlands
  • PROS, Houston
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A version of this article originally appeared on CultureMap.com.

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