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.

Here's what startups took home wins at CERAWeek. Photo by Natalie Harms/InnovationMap

8 energy tech startups recognized at Houston's CERAWeek pitch competition

taking home the W

Over 200 startups participated in CERAWeek this year, and 18 of those companies pitched at a Greater Houston Partnership event.

The Houston Energy Transition Initiative, an initiative to promote Houston's work within the energy transition, hosted its second annual HETI Energy Ventures Competition at CERAWeek Innovation Agora. The competition was divided into four categories. The first batch of startups consisted of five companies from the Texas Entrepreneurship Exchange for Energy, or TEX-E, a collaboration with Greentown Labs, MIT’s Martin Trust Center for Entrepreneurship, and universities across Texas.

The winning startups shared $50,000 of prizes, sponsored by TEX-E. Houston-based Helix Earth Technologies — which has developed high-speed, high-efficiency filter systems derived from technology originating at NASA — won both the first place prize and fan favorite for the category. Helix's co-founders, Rawand Rasheed and Brad Husick from Rice University, walked away with $25,000 in prizes

Founded by Bryon Praslicka, Daniel Zamarron, and Craig Newman from Texas A&M University, Flux Works LLC, and its magnetic gear technology, took second place and $15,000 home. Tierra Climate, a two-sided marketplace for carbon offsets and other sustainability efforts founded by Emma Konet and Jacob Mansfield from Rice University, won third place and $10,000.

Helix Earth Technologies walked away with the top prize of the TEX-E category. Photo via greentownlabs.com

The next sets of startup pitches we broken down by funding stages — pre-seed and seed, series A, and series B and beyond.

Red Shift Energy, uses plasma energy to produce hydrogen from hydrogen sulfide, won fan favorite in the pre-seed and seed category sponsored by HX Venture Fund. A member of Halliburton Labs, the company also was recognized as Chevron favorite.

Per the judging panel, CanaGas won the title of most promising in the pre-seed and seed category sponsored by Alchemy Industrial. The Canadian company liquifies natural gas without costly cryogenics or stripping of the gas.

Houston-based Criterion Energy Partners won both the most-promising series A company category sponsored by SLB, but also the fan favorite series A category sponsored by Guerrella LLC. A geothermal energy tech company, Criterion was also a member of Rice's inaugural Clean Energy Accelerator cohort.

OptiSeis Solutions also won in both categories for the series B track. The company, a geophysical acquisition design and software company, won the title of most promising in the series B category sponsored by Pana LCE Investments and the series B fan favorite category sponsored by Halliburton Labs.

Lastly, the competition named the Most Impactful DEI, a category sponsored by Pana LCE Investments. Austin-based Gazelle Ecosystems, a social innovation startup with eco-solutions for corporations, won that category.

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This article originally ran on InnovationMap.

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Major Houston energy companies join new Carbon Measures coalition

green team

Six companies with a large presence in the Houston area have joined a new coalition of companies pursuing a better way to track the carbon emissions of products they manufacture, purchase and finance.

Houston-area members of the Carbon Measures coalition are:

  • Spring-based ExxonMobil
  • Air Liquide, whose U.S. headquarters is in Houston
  • Mitsubishi Heavy Industries, whose U.S. headquarters is in Houston
  • Honeywell, whose Performance Materials and Technologies business is based in Houston.
  • BASF, whose global oilfield solutions business is based in Houston
  • Linde, whose Linde Engineering Americas business is based in Houston

Carbon Measures will create an accounting framework that eliminates double-counting of carbon pollution and attributes emissions to their sources, said Amy Brachio, the group’s CEO. The model is expected to take two years to develop, and between five and seven years to scale up, Bloomberg reported.

The coalition wants to create a system that will “unleash markets and competition,” unlock investments and speed up the pace of emissions reduction, said Brachio, former vice chair of sustainability at professional services firm EY.

“If you can’t measure it, you can’t manage it,” said Darren Woods, chairman and CEO of ExxonMobil. “The first step to reducing global emissions is to know where they’re coming from — and today, we don’t have an accurate system to do this.”

Other members of the coalition include BlackRock-owned Global Infrastructure Partners, Banco Satanader, EY and NextEra Energy.

“Transparent and consistent emissions accounting is not just a technical necessity — it’s a strategic imperative. It enables smarter decisions and accelerates real progress across industries and borders,” said Ken West, president and CEO of Honeywell Energy and Sustainability Solutions.

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.