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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Houston hardtech accelerator names 8 scientists to 2025 cohort

ready, set, activate

National hardtech-focused organization Activate has named its 2025 cohort of scientists, which includes new members to Activate Houston.

The Houston hub was introduced last year, and joins others in Boston, New York, and Berkley, California—where Activate is headquartered. The organization also offers a virtual and remote cohort, known as Activate Anywhere. Collectively, the 2025 Activate Fellowship consists of 47 scientists and engineers from nine U.S. states.

This year's cohort comprises subject matter experts across various fields, including quantum, robotics, biology, agriculture, energy and direct air capture.

Activate aims to support scientists at "the outset of their entrepreneurial journey." It partners with U.S.-based funders and research institutions to support its fellows in developing high-impact technology. The fellows receive a living stipend, connections from Activate's robust network of mentors and access to a curriculum specific to the program for two years.

“Science entrepreneurship is the origin story of tomorrow’s industries,” Cyrus Wadia, CEO of Activate, said in an announcement. “The U.S. has long been a world center for science leadership and technological advancement. When it comes to solving the world’s biggest challenges, hard-tech innovation is how we unlock the best solutions. From infrastructure to energy to agriculture, these Activate Fellows are the bold thinkers who are building the next generation of science-focused companies to lead us into the future.”

The Houston fellows selected for the 2025 class include:

  • Jonathan Bessette, founder and CEO of KIRA, which uses its adaptive electrodialysis system to treat diverse water sources and reduce CO2 emissions
  • Victoria Coll Araoz, co-founder and chief science officer of Florida-based SEMION, an agricultural technology company developing pest control strategies by restoring crops' natural defenses
  • Eugene Chung, co-founder and CEO of Lift Biolabs, a biomanufacturing company developing low-cost, nanobubble-based purification reagents. Chung is completing his Ph.D. in bioengineering at Rice University.
  • Isaac Ju, co-founder of EarthFlow AI, which has developed an AI-powered platform for subsurface modeling, enabling the rapid scaling of carbon storage, geothermal energy and lithium extraction
  • Junho Lee, principal geotechnical engineer of Houston-based Deep Anchor Solutions, a startup developing innovative anchoring systems for floating renewables and offshore infrastructure
  • Sotiria (Iria) Mostrou, principal inventor at Houston-based Biosimo Chemicals, a chemical engineering startup that develops and operates processes to produce bio-based platform chemicals
  • Becca Segel, CEO and founder of Pittsburgh-based FlowCellutions, which prevents power outages for critical infrastructure such as hospitals, data centers and the grid through predictive battery diagnostics
  • Joshua Yang, CEO and co‑founder of Cambridge, Massachusetts-based Brightlight Photonics, which develops chip-scale titanium: sapphire lasers to bring cost-effective, lab-grade performance to quantum technologies, diagnostics and advanced manufacturing

The program, led locally by Houston Managing Director Jeremy Pitts, has supported 296 Activate fellows since the organization was founded in 2015. Members have gone on to raise roughly $4 billion in follow-on funding, according to Activate's website.

Activate officially named its Houston office in the Ion last year.

Charlie Childs, co-founder and CEO of Intero Biosystems, which won both the top-place finish and the largest total investment at this year's Rice Business Plan Competition, was named to the Activate Anywhere cohort. Read more about the Boston, New York, Berkley and Activate Anywhere cohorts here.

Houston team’s discovery brings solid-state batteries closer to EV use

A Better Battery

A team of researchers from the University of Houston, Rice University and Brown University has uncovered new findings that could extend battery life and potentially change the electric vehicle landscape.

The team, led by Yan Yao, the Hugh Roy and Lillie Cranz Cullen Distinguished Professor of Electrical and Computer Engineering at UH, recently published its findings in the journal Nature Communications.

The work deployed a powerful, high-resolution imaging technique known as operando scanning electron microscopy to better understand why solid-state batteries break down and what could be done to slow the process.

“This research solves a long-standing mystery about why solid-state batteries sometimes fail,” Yao, corresponding author of the study, said in a news release. “This discovery allows solid-state batteries to operate under lower pressure, which can reduce the need for bulky external casing and improve overall safety.”

A solid-state battery replaces liquid electrolytes found in conventional lithium-ion cells with a solid separator, according to Car and Driver. They also boast faster recharging capabilities, better safety and higher energy density.

However, when it comes to EVs, solid-state batteries are not ideal since they require high external stack pressure to stay intact while operating.

Yao’s team learned that tiny empty spaces, or voids, form within the solid-state batteries and merge into a large gap, which causes them to fail. The team found that adding small amounts of alloying elements, like magnesium, can help close the voids and help the battery continue to function. The team captured it in real-time with high-resolution videos that showed what happens inside a battery while it’s working under a scanning electron microscope.

“By carefully adjusting the battery’s chemistry, we can significantly lower the pressure needed to keep it stable,” Lihong Zhao, the first author of this work, a former postdoctoral researcher in Yao’s lab and now an assistant professor of electrical and computer engineering at UH, said in the release. “This breakthrough brings solid-state batteries much closer to being ready for real-world EV applications.”

The team says it plans to build on the alloy concept and explore other metals that could improve battery performance in the future.

“It’s about making future energy storage more reliable for everyone,” Zhao added.

The research was supported by the U.S. Department of Energy’s Battery 500 Consortium under the Vehicle Technologies Program. Other contributors were Min Feng from Brown; Chaoshan Wu, Liqun Guo, Zhaoyang Chen, Samprash Risal and Zheng Fan from UH; and Qing Ai and Jun Lou from Rice.

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This article originally appeared on EnergyCaptialHTX.com.

Rice biotech accelerator appoints 2 leading researchers to team

Launch Pad

The Rice Biotech Launch Pad, which is focused on expediting the translation of Rice University’s health and medical technology discoveries into cures, has named Amanda Nash and Kelsey L. Swingle to its leadership team.

Both are assistant professors in Rice’s Department of Bioengineering and will bring “valuable perspective” to the Houston-based accelerator, according to Rice. 

“Their deep understanding of both the scientific rigor required for successful innovation and the commercial strategies necessary to bring these technologies to market will be invaluable as we continue to build our portfolio of lifesaving medical technologies,” Omid Veiseh, faculty director of the Launch Pad, said in a news release.

Amanda Nash

Nash leads a research program focused on developing cell communication technologies to treat cancer, autoimmune diseases and aging. She previously trained as a management consultant at McKinsey & Co., where she specialized in business development, portfolio strategy and operational excellence for pharmaceutical and medtech companies. She earned her doctorate in bioengineering from Rice and helped develop implantable cytokine factories for the treatment of ovarian cancer. She holds a bachelor’s degree in biomedical engineering from the University of Houston.

“Returning to Rice represents a full-circle moment in my career, from conducting my doctoral research here to gaining strategic insights at McKinsey and now bringing that combined perspective back to advance Houston’s biotech ecosystem,” Nash said in the release. “The Launch Pad represents exactly the kind of translational bridge our industry needs. I look forward to helping researchers navigate the complex path from discovery to commercialization.”

Kelsey L. Swingle

Swingle’s research focuses on engineering lipid-based nanoparticle technologies for drug delivery to reproductive tissues, which includes the placenta. She completed her doctorate in bioengineering at the University of Pennsylvania, where she developed novel mRNA lipid nanoparticles for the treatment of preeclampsia. She received her bachelor’s degree in biomedical engineering from Case Western Reserve University and is a National Science Foundation Graduate Research Fellow.

“What draws me to the Rice Biotech Launch Pad is its commitment to addressing the most pressing unmet medical needs,” Swingle added in the release. “My research in women’s health has shown me how innovation at the intersection of biomaterials and medicine can tackle challenges that have been overlooked for far too long. I am thrilled to join a team that shares this vision of designing cutting-edge technologies to create meaningful impact for underserved patient populations.”

The Rice Biotech Launch Pad opened in 2023. It held the official launch and lab opening of RBL LLC, a biotech venture creation studio in May. Read more here.

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