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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UTHealth Houston officially opens new tower in TMC's Helix Park

open for innovation

UTHealth Houston School of Public Health recently opened its new state-of-the-art tower in the Texas Medical Center’s Helix Park.

The 350,000-square-foot, 10-story campus at 1930 Old Spanish Trail was celebrated with an official ribbon-cutting ceremony on Oct. 28. The $229 million project will consolidate all UTHealth Houston School of Public Health operations into one facility. It will also connect students who are at the Austin, Brownsville, Dallas, El Paso and San Antonio campuses with peers and faculty through digital and distance learning.

Disciplines taught in the new tower will include epidemiology, genetics, nutrition, health policy, data science and health promotion, UTHealth shared when the building first broke ground in 2023.

Architects Kirksey Architecture and Smith Group designed the building, and Vaughn Construction served as general contractor. The facility features labs for studying human disease, classrooms and spaces to support interdisciplinary and community-based research, a broadcast studio and a teaching kitchen. A skybridge over Old Spanish Trail connects the new tower with a plaza that's shared with MD Anderson.

“This new facility reflects the kind of forward-looking investment that will serve Texans for generations,” Janiece Longoria, vice chairman of the UT System Board of Regents, said in a news release. “By creating an environment where talented people can learn, collaborate, and pursue new ideas, UTHealth Houston is building capacity to meet the challenges of tomorrow while strengthening its impact across our state.”

UTHealth says the system aims for the new campus to expand on collaborative research efforts and continue graduate education, as enrollment at the School of Public Health has increased by 27 percent over the last five years.

“This new building, with its state-of-the-art education technology and learning environment, will strengthen and advance the school’s mission to educate and train the next generation of experts who will advance scientific discovery, shape evidence-based health policy, and lead innovative solutions to the complex health challenges in communities throughout Texas and across the nation,” Kevin Morano, senior vice president, provost and chief academic officer of UTHealth Houston, added in a news release.

Attending the ceremony were Dr. Melina R. Kibbe, UTHealth Houston president and Alkek Williams Distinguished Chair; Eric Boerwinkle, dean, M. David Low Chair in Public Health and Kozmetsky Family Chair in Human Genetics at the School of Public Health; Texas State Representative Lauren Ashley Simmons, Texas House District 146; representatives of the offices of Senator John Cornyn and Harris County Commissioner Rodney Ellis; and Dr. Theresa Tran, director of the Houston Health Department.

"This building represents far more than a home for our school,” Boerwinkle added in the release. “It represents the people who make our mission possible: the faculty, staff, and students who fill each laboratory and classroom with curiosity, discovery, and purpose to improve the population’s quality of life.”

Rice University breaks ground on new innovation hub, The Arc

breaking ground

Construction is officially underway on Rice University's The Arc in Houston’s Ion District.

The university broke ground on the 200,000-square-foot research, corporate innovation and office building on Nov. 4. The facility will share a plaza with the existing Ion building, fostering collaboration within the innovation space, according to Rice.

“The Arc will bring Rice’s extraordinary research and talent and Houston’s impactful innovation ecosystem into even closer connection with the industries and innovators working to solve some of the world’s most consequential challenges,” Rice President Reginald DesRoches said in an announcement. “That constant exchange of ideas and expertise will help move discoveries more rapidly from the laboratory to real-world impact.”

Construction is scheduled to be completed by Q2 2028. Rice Real Estate Co. is developing the project, and Rice University will occupy about 80,000 square feet in the building (about 40 percent). Preleasing has begun, with floor plans ranging from 28,000 to 31,000 square feet.

The Arc will feature conference and meeting spaces, an amenity lounge, fitness center, outdoor plazas, underground parking, and on-site retail and dining, according to the release.

It aims to host tenants focused on artificial intelligence and machine learning, data science, robotics, quantum science and engineering and energy, including Rice's new AI Foundry.

Rice says the AI Foundry will be a space where university experts and partners can support organizations with AI challenges. Rice recently committed to hiring 75 new AI-focused faculty and announced plans to launch a new Master of Artificial Intelligence (MAI) next fall.

“The AI Foundry is exactly the kind of collaboration the Arc is designed to enable,” Amy Dittmar, the Howard R. Hughes Provost and executive vice president for academic affairs at Rice, added in the release. “By bringing Rice researchers together with industry partners in a shared environment, we can accelerate the movement of ideas from research into practical applications while helping organizations build the capabilities they need to succeed as AI continues to evolve.

Developers of The Arc are targeting LEED Gold certification by incorporating smart building automation and energy-saving features into the project's design. Rice first announced the project in September 2025.

Rendering courtesy Bogza

Houston battery tech startup FlowCellutions acquired by Katy energy co.

M&A

Katy-based TerraFlow Energy, an energy storage and infrastructure company, has acquired Houston-based battery technology startup FlowCellutions. Financial terms weren’t disclosed.

FlowCellutions still operates under its established name, but with the tagline “A TerraFlow Energy Company.” Becca Segel, founder and CEO of FlowCellutions, now runs the business as its president.

FlowCellutions specializes in electrochemical sensing, diagnostics, analytics, and testing that offer insights into battery chemistry, charging capabilities, and system performance.

“FlowCellutions has always been focused on developing better ways to understand what is happening inside a flow battery and using that information to improve how these systems perform,” Segal said in a press release. “Joining TerraFlow gives us the opportunity to apply that work at a much larger scale while continuing to build the capabilities and expertise that make FlowCellutions unique.”

The FlowCellutions platform supports data centers and other heavy users of power. It’s designed to help reduce operating costs, prevent failures and costly downtime, and extend battery lifetime from about seven years to more than 30 years.

Segel founded the company in 2022. A member of Greentown Labs, the company raised more than $2 million in non-dilutive funding and received $1.5 million in National Science Foundation funding earlier this year.

FlowCellutions is one of five finalists in the Energy Transition Business category of InnovationMap’s 2026 Houston Innovation Awards.

“FlowCellutions brings a depth of scientific and technical expertise that fits naturally with where TerraFlow is going,” Jon Parrella, CEO of TerraFlow, said in the release.

“As we move from developing these systems to deploying them at commercial scale, understanding performance at a deeper level matters,” he said. “Bringing FlowCellutions into TerraFlow strengthens that capability and gives both teams more opportunity to advance the technology.”TerraFlow, founded in 2024, develops long-duration energy storage and power infrastructure for data centers, industrial facilities, utilities and other large power consumers.

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This article originally appeared on EnergyCapitalHTX.com.

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