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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Investment bank opens energy-focused office in Houston

new to hou

Investment bank Cohen & Co. Capital Markets has opened a Houston office to serve as the hub of its energy advisory business and has tapped investment banking veteran Rahul Jasuja as the office’s leader.

Jasuja joined Cohen & Co. Capital Markets, a subsidiary of financial services company Cohen & Co., as managing director, and head of energy and energy transition investment banking. Cohen’s capital markets arm closed $44 billion worth of deals last year.

Jasuja previously worked at energy-focused Houston investment bank Mast Capital Advisors, where he was managing director of investment banking. Before Mast Capital, Jasuja was director of energy investment banking in the Houston office of Wells Fargo Securities.

“Meeting rising [energy] demand will require disciplined capital allocation across traditional energy, sustainable fuels, and firm, dispatchable solutions such as nuclear and geothermal,” Jasuja said in a news release. “Houston remains the center of gravity where capital, operating expertise, and execution come together to make that transition investable.”

The Houston office will focus on four energy verticals:

Energy systems such as nuclear and geothermal
Energy supply chains
Energy-transition fuel and technology
Traditional energy

“We are making a committed investment in Houston because we believe the infrastructure powering AI, defense, and energy transition — from nuclear to rare-earth technology — represents the next secular cycle of value creation,” Jerry Serowik, head of Cohen & Co. Capital Markets, added in the release.

Houston cleantech startup Helix Earth lands $1.2M NSF grant

federal funding

Renewable equipment manufacturer Helix Earth Technologies is one of three Houston-based companies to secure federal funding through the Small Business Innovation Research (SBIR) Phase II grant program in recent months.

The company—which was founded based on NASA technology, spun out of Rice University and has been incubated at Greentown Labs—has received approximately $1.2 million from the National Science Foundation to develop its high-efficiency retrofit dehumidification systems that aim to reduce the energy consumption of commercial AC units. The company reports that its technology has the potential to cut AC energy use by up to 50 percent.

"This award validates our vision and propels our impact forward with valuable research funding and the prestige of the NSF stamp of approval," Rawand Rasheed, Helix CEO and founder, shared in a LinkedIn post. "This award is a reflection our exceptional team's grit, expertise, and collaborative spirit ... This is just the beginning as we continue pushing for a sustainable future."

Two other Houston-area companies also landed $1.2 million in NSF SBIR Phase II funding during the same period:

Resilitix Intelligence, a disaster AI startup that was founded shortly after Hurricane Harvey, that works to "reduce the human and economic toll of disasters" by providing local and state organizations and emergency response teams with near-real-time, AI-driven insights to improve response speed, save lives and accelerate recovery
Conroe-based Fluxworks Inc., founded in 2021 at Texas A&M, which provides magnetic gear technology for the space industry that has the potential to significantly enhance in-space manufacturing and unlock new capabilities for industries by allowing advanced research and manufacturing in microgravity

The three grants officially rolled out in early September 2025 and are expected to run through August 2027, according to the NSF. The SBIR Phase II grants support in-depth research and development of ideas that showed potential for commercialization after receiving Phase I grants from government agencies.

However, congressional authority for the program, often called "America's seed fund," expired on September 30, 2025, and has stalled since the recent government shutdown. Government agencies cannot issue new grants until Congress agrees on a path forward. According to SBIR.gov, "if no further action is taken by Congress, federal agencies may not be able to award funding under SBIR/STTR programs and SBIR/STTR solicitations may be delayed, cancelled, or rescinded."

Mars Materials makes breakthrough in clean carbon fiber production

Future of Fiber

Houston-based Mars Materials has made a breakthrough in turning stored carbon dioxide into everyday products.

In partnership with the Textile Innovation Engine of North Carolina and North Carolina State University, Mars Materials turned its CO2-derived product into a high-quality raw material for producing carbon fiber, according to a news release. According to the company, the product works "exactly like" the traditional chemical used to create carbon fiber that is derived from oil and coal.

Testing showed the end product met the high standards required for high-performance carbon fiber. Carbon fiber finds its way into aircraft, missile components, drones, racecars, golf clubs, snowboards, bridges, X-ray equipment, prosthetics, wind turbine blades and more.

The successful test “keeps a promise we made to our investors and the industry,” Aaron Fitzgerald, co-founder and CEO of Mars Materials, said in the release. “We proved we can make carbon fiber from the air without losing any quality.”

“Just as we did with our water-soluble polymers, getting it right on the first try allows us to move faster,” Fitzgerald adds. “We can now focus on scaling up production to accelerate bringing manufacturing of this critical material back to the U.S.”

Mars Materials, founded in 2019, converts captured carbon into resources, such as carbon fiber and wastewater treatment chemicals. Investors include Untapped Capital, Prithvi Ventures, Climate Capital Collective, Overlap Holdings, BlackTech Capital, Jonathan Azoff, Nate Salpeter and Brian Andrés Helmick.

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