Houston startup gears up to deliver geothermal energy

ready to drill

Criterion Energy Partners is aiming to be a next-gen energy company. Photo via Getty Images

Sean Marshall and Danny Rehg founded Criterion Energy Partners in 2020 with the hope that geothermal energy could be the cleaner, safer wave of the future. Less than three years later, the team is close to making their plan a reality thanks to a geothermal well that they hope to drill this year.

Entrepreneurship wasn’t always part of the plan for either partner. When Marshall enrolled in the MBA program at Rice University’s Jones School of Business in 2016, he had a successful career at Credit Suisse and had his eye set on a future political career. But then he met classmate Rehg, whose background was in petroleum engineering. Their wives were both attorneys in the Houston district attorney’s office and the couples became fast friends. They also realized that, as Marshall now puts it, Rehg knew how to drill wells and he knew how to make deals.

In the ensuing years, both Rehg and Marshall's careers evolved and, eventually, the pair started looking for other opportunities. That’s when they read an article in Rolling Stone about geothermal energy.

“It was really a place where it really felt like this was something we were put here to do,” says Marshall.

Marshall and Rehg spent the ensuing months “like rats in a dumpster” learning about the players and opportunities in the geothermal industry and built from there. They learned about Pleasant Bayou Power Plant, a 1989 geothermal energy project based in Brazoria County that was backed by the U.S. Department of Energy.

Last summer, Criterion Energy Partners, a member of Greentown Houston, closed on a 10,000-acre lease around the site of Pleasant Bayou.

"We hope by the end of this year we will be generating electrons,” says Marshall.

Though the company has a patented technology that connects wells to the grid, called Criterion Geothermal System, Marshall says that some of the best advice he’s gotten was, “Don’t fall in love with your technology; fall in love with the problem.” The 2021 Texas freeze reminded the founders what that was.

“People were looking for cleaner, lower-emission power sources and [there was] a need for energy resiliency,” says Marshall, explaining that the freeze created an ideal situation for the company, as people began to think more outside the grid.

The year 2022 was a big one for Criterion Energy Partners. Oil and gas powerhouse Patterson-UTI invested in the company, followed by funding from the Department of Energy. The money not only allowed Criterion Energy Partners to lease their land, they are also now paying 12 salaries, including those of the founders. The team offices in The Cannon’s Esperson coworking space.

“Our mission is to make geothermal commercially viable everywhere,” says Marshall. “I still believe in that.”

However, Criterion Energy Partners may be even bigger than proving an alternative energy source. Marshall says that geothermal is the foundation on which they are building “a next-generation energy company.” Criterion Energy Partners could be the more stable basis for a whole new energy system.

Sean Marshall and Danny Rehg founded Criterion Energy Partners in 2020. Photos courtesy

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This article originally ran on InnovationMap.

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Wind and solar supplied over a third of ERCOT power, report shows

power report

Since 2023, wind and solar power have been the fastest-growing sources of electricity for the Electric Reliability Council of Texas (ERCOT) and increasingly are meeting stepped-up demand, according to a new report from the U.S. Energy Information Administration (EIA).

The report says utility-scale solar generated 50 percent more electricity for ERCOT in the first nine months this year compared with the same period in 2024. Meanwhile, electricity generated by wind power rose 4 percent in the first nine months of this year versus the same period in 2024.

Together, wind and solar supplied 36 percent of ERCOT’s electricity in the first nine months of 2025.

Heavier reliance on wind and solar power comes amid greater demand for ERCOT electricity. In the first nine months of 2025, ERCOT recorded the fastest growth in electricity demand (5 percent) among U.S. power grids compared with the same period last year, according to the report.

“ERCOT’s electricity demand is forecast to grow faster than that of any other grid operator in the United States through at least 2026,” the report says.

EIA forecasts demand for ERCOT electricity will climb 14 percent in the first nine months of 2026 compared with the same period this year. This anticipated jump coincides with a number of large data centers and cryptocurrency mining facilities coming online next year.

The ERCOT grid covers about 90 percent of Texas’ electrical load.

Micro-nuclear reactor to launch next year at Texas A&M innovation campus

nuclear pilot

The Texas A&M University System and Last Energy plan to launch a micro-nuclear reactor pilot project next summer at the Texas A&M-RELLIS technology and innovation campus in Bryan.

Washington, D.C.-based Last Energy will build a 5-megawatt reactor that’s a scaled-down version of its 20-megawatt reactor. The micro-reactor initially will aim to demonstrate safety and stability, and test the ability to generate electricity for the grid.

The U.S. Department of Energy (DOE) fast-tracked the project under its New Reactor Pilot Program. The project will mark Last Energy’s first installation of a nuclear reactor in the U.S.

Private funds are paying for the project, which Robert Albritton, chairman of the Texas A&M system’s board of regents, said is “an example of what’s possible when we try to meet the needs of the state and tap into the latest technologies.”

Glenn Hegar, chancellor of the Texas A&M system, said the 5-megawatt reactor is the kind of project the system had in mind when it built the 2,400-acre Texas A&M-RELLIS campus.

The project is “bold, it’s forward-looking, and it brings together private innovation and public research to solve today’s energy challenges,” Hegar said.

As it gears up to build the reactor, Last Energy has secured a land lease at Texas A&M-RELLIS, obtained uranium fuel, and signed an agreement with DOE. Founder and CEO Bret Kugelmass said the project will usher in “the next atomic era.”

In February, John Sharp, chancellor of Texas A&M’s flagship campus, said the university had offered land at Texas A&M-RELLIS to four companies to build small modular nuclear reactors. Power generated by reactors at Texas A&M-RELLIS may someday be supplied to the Electric Reliability Council of Texas (ERCOT) grid.

Also in February, Last Energy announced plans to develop 30 micro-nuclear reactors at a 200-acre site about halfway between Lubbock and Fort Worth.

Rice University partners with Australian co. to boost mineral processing, battery innovation

critical mineral partnership

Rice University and Australian mineral exploration company Locksley Resources have joined together in a research partnership to accelerate the development of antimony processing in the U.S. Antimony is a critical mineral used for defense systems, electronics and battery storage.

Rice and Locksley will work together to develop scalable methods for extracting and utilizing antimony. Currently, the U.S. relies on imports for nearly all refined antimony, according to Rice.

Locksley will fund the research and provide antimony-rich feedstocks and rare earth elements from a project in the Mojave Desert. The research will explore less invasive hydrometallurgical techniques for antimony extraction and explore antimony-based materials for use in batteries and other energy storage applications.

“This strategic collaboration with Rice marks a pivotal step in executing Locksley’s U.S. strategy,” Nathan Lude, chairman of Locksley Resources, said in a news release. “By fast-tracking our research program, we are helping rebuild downstream capacity through materials innovation that the country urgently requires.”

Pulickel Ajayan, the Benjamin M. and Mary Greenwood Anderson Professor of Materials Science and Nanoengineering at Rice, is the principal investigator of the project.

“Developing scalable, domestic pathways for antimony processing is not only a scientific and engineering challenge but also a national strategic priority,” Ajayan said in the news release. “By combining Rice’s expertise in advanced materials with Locksley’s resources, we can address a critical supply chain gap and build collaborations that strengthen U.S. energy resilience.”

The Rice Advanced Materials Institute (RAMI) will play a major role in supporting the advancement of technology and energy-storage applications.

“This partnership aligns with our mission to lead in materials innovations that address national priorities,” Lane Martin, director of RAMI, said in a news release. “By working with Locksley, we are helping to build a robust domestic supply chain for critical materials and support the advancement of next-generation energy technologies.”

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