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.

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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14 climatech startups join Greentown Houston in first half of 2026

green team

Climatech incubator Greentown Labs reports that 14 startups have joined its Houston community so far this year.

The companies are among 30 new startups to have joined Greentown Houston and Greentown Boston in 2026. Four of the companies are headquartered in Houston.

The startups are working on a range of "hydrogen-powered heavy-duty transport to AI-driven grid interconnection," according to Greentown.

The local startups that joined Greentown Houston include:

Houston-based Focis AI, which transforms industrial laser scans into structured asset intelligence to automatically identify, classify and map components in refineries and plants
Houston-based Iron Lattice, which develops next-generation memory technology for AI and high-performance computing that improves energy efficiency, endurance and scalability while remaining compatible with existing semiconductor manufacturing
Houston-based Orbital Arc, which is developing a new ion engine designed to improve the efficiency and scalability of spacecraft propulsion from low Earth orbit to deep space
Houston-based Sustain Energy LLC, which delivers cleaner, lower-cost fuel to industrial customers in pipeline-absent, underserved markets, cutting their energy costs and emissions with no infrastructure investment on their end

Other startups from around the world joined the Houston incubator in the same time period, including:

Ankara-based AIS Field, which develops robotic, AI-assisted non-destructive inspection systems, including submersible tank and boiler crawlers
San Francisco-based Armada AI, which builds rapidly deployable modular and edge data centers that run on local, stranded, or renewable power
San Francisco-based Armeta, which turns complex engineering drawings and legacy documentation into structured, usable data
Pittsburgh-based Atlas Robotics, which develops a Physical AI platform that powers autonomous material-handling robots and AI-guided forklifts
Ghana-based Cocoa Potash, which transforms high-emissions agricultural waste from cocoa, coconut, and palm-nut into organic potash, fertilizer and renewable energy
Israel-based Criaterra, which produces low-carbon, cement-free building materials
Italy-based ETAK, which manufactures modular reactors that convert solid waste into clean syngas
Kenya-based FelixFusion, which uses its Felix platform to model every grid connection point, including capacity, upgrade costs, and constraints
San Diego-based Gemini Energy, which builds next-generation fuel cells for data-center power
Tokyo-based Hibot, which develops robotic systems for inspecting and maintaining infrastructure in hazardous, hard-to-access environments
Austin-based Sheetak, which designs and manufactures thermoelectric coolers, generators, and assemblies for solid-state cooling and energy harvesting
The Netherlands-based ToPerform, which makes AI-powered, non-intrusive fouling sensors that monitor pipelines around the clock and predict the optimal cleaning time

Another 16 startups joined Greentown's Boston incubator. See the full list of new members here.

More than 100 startups joined Greentown last year, according to an end-of-year reflection shared by Greentown CEO Georgina Campbell Flatter. Read more about them here.

Houston cleantech startup secures $134M to develop ‘superhot’ geothermal plant

deep round

Houston-based Quaise Energy, a producer of utility-scale geothermal power, raised $134 million in a Series B round to advance its “superhot” geothermal power plant.

Climate-focused San Francisco-based investment firm Prelude Ventures led the round, with participation from JERA Co., Japan’s largest power generation company, and Idemitsu Kosan, one of Japan’s largest energy companies. Nearly all existing investors, including cleantech-focused investment firm Safar Partners, participated in the round.

“We have backed Quaise since the beginning because we believed accessing superhot rock would unlock geothermal energy at a scale the world has never seen,” Mark Cupta, managing director at Prelude Ventures, said in a press release.

The startup expects more equity and debt deals to close “imminently.” Quaise has raised $230 million since its founding in 2018.

Quaise says some of the fresh funding will go toward building the world’s first commercial-scale “superhot” geothermal power plant —Project Obsidian in central Oregon. In addition, Quaise is earmarking money for continued development and commercialization of its millimeter-wave drilling system toward depths exceeding 5 kilometers (about 16,400 feet).

Quaise uses a millimeter-wave drilling system developed at the Massachusetts Institute of Technology to remove rock at depths and temperatures that aren’t economically feasible with conventional drilling. With this technology, Quaise can reach rock at temperatures of around 570 degrees to 930 degrees in most places worldwide, enabling construction of geothermal systems that rival fossil fuels and nuclear energy in power density and that rival renewables in cost.

“Our ambition is to power civilization with Earth's most compelling energy source. This round takes us from field-proven technology to first commercial revenues,” Carlos Araque, co-founder, president and CEO of Quaise, added in the release.

Quaise has demonstrated the capability of its millimeter-wave drilling system at its Central Texas test site, drilling more than about 330 feet through granite in 2025—the first time the technology penetrated basement rock at full scale in the field. The company is approaching a depth of about 3,300 feet at the same site.

Construction of Project Obsidian is underway at Oregon’s Deschutes National Forest. The project, which has the potential to generate gigawatt-scale power, is slated to deliver electricity to the Pacific Northwest grid by 2030.

Shell expands lower-carbon energy solutions while cutting emissions

The View from HETI

Shell’s approach to sustainable development reflects an integrated value chain perspective—reducing emissions from oil and gas production, transforming downstream businesses to offer more low-carbon solutions, and building new energy businesses at scale. The company’s 31% reduction in Scope 1 and 2 operational emissions since 2016 demonstrates that this integrated strategy delivers results.

Three Strategic Priorities Drive Progress

Leading Integrated Gas: Shell is growing its world-leading LNG business with lower carbon intensity, meeting rising demand for natural gas as a transition fuel and foundation for renewable energy integration.

Advantaged Upstream: The company is cutting emissions from oil and gas production while keeping output stable, proving that operational excellence can reduce environmental impact without sacrificing energy security.

Differentiated Downstream, Renewables, and Energy Solutions: Shell is transforming its businesses to offer more low-carbon solutions while reducing sales of traditional oil products, positioning the company for the evolving energy market.

Shell’s emissions reductions are happening across global operations:

United States: Significant emissions cuts from production assets through operational efficiency and technology deployment

Malaysia & Philippines: Emissions reduction programs at offshore operations demonstrating that low-carbon production works in diverse environments

Norway: Continued emissions intensity improvements from mature assets, showing that even older fields can decarbonize

Whale Partnership Demonstrates Innovation

Shell’s recent partnership with Chevron at the Whale deepwater asset showcases what’s possible with next-generation project design. By integrating emissions reduction strategies from the start, the partnership has lowered the greenhouse gas intensity approximately 30% over the project lifecycle relative to similar deepwater oil and gas production assets.

Shell’s strategy to deliver more value with less emissions includes climate change transition plans, mitigation actions and decarbonization levers supported by a suite of processes and greenhouse gas emission reduction targets such as:

2025 Results:

Eliminated routine flaring from upstream operations

Maintained methane emissions intensity below 0.2%

By 2030:

Halve Scope 1 and 2 emissions under operational control (vs. 2016)

Achieve near-zero methane emissions

Reduce Scope 3 net carbon intensity (NCI) by 15-20% (vs. 2016)

Cut customer emissions from oil products by 15-20% (vs. 2021)

By 2050:

Achieve net zero emissions across Scopes 1, 2, and 3

Across all strategic initiatives, Shell prioritizes trading and optimization capabilities that maximize value while minimizing emissions. This commercial approach ensures that the company’s energy transition strategy creates long-term shareholder value while advancing climate goals.

Shell is building an integrated energy business for the low-carbon future by delivering the energy products customers need today while investing in the solutions they’ll need tomorrow.

As a steering-level member of HETI, Shell exemplifies the leadership and commitment required to transform Houston’s energy sector while maintaining global energy security.

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This article originally appeared on the Greater Houston Partnership's Houston Energy Transition Initiative blog . Explore Shell’s energy transition strategy at: https://www.shell.us/about-us/sustainability.html, and read the full analysis here: https://htxenergytransition.org/wp-content/uploads/2025/08/07.18.25-HETI-Leadership-Narrative-Report-V2_pages-1-2.pdf

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