Twelve local startups have joined Greentown Houston, along with others from around the world. Photo courtesy Greentown Labs.

More than 40 climatetech startups joined the Greentown Labs Houston community in the second half of 2025. Twelve hail from the Bayou City.

The companies are among a group of nearly 70 that joined the climatetech incubator, which is co-located in Houston and Boston, in Q3 and Q4.

The new companies that have joined the Houston incubator specialize in a variety of clean energy applications, from green hydrogen-producing water-splitting cycles to drones that service wind turbines.

The local startups that joined Greentown Houston include:

  • Houston-based Wise Energie, which delivers turnkey microgrids that blend vertical-axis wind, solar PV, and battery storage into a single, silent system.
  • The Woodlands-based Resollant, which is developing compact, zero-emissions hydrogen and carbon reactors to provide low-cost, scalable clean hydrogen and high-purity carbon for the energy and manufacturing sectors.
  • Houston-based ClarityCastle, which designs and manufactures modular, soundproof work pods that replace traditional drywall construction with reusable, low-waste alternatives made from recycled materials.
  • Houston-based WattSto Energy, which manufactures vanadium redox flow batteries to deliver long-duration storage for both grid-scale projects and off-grid microgrids.
  • Houston-based AMPeers, which delivers advanced, high-temperature superconductors in the U.S. at a fraction of traditional costs.
  • Houston-based Biosimo, which is developing bio-based platform chemicals, pioneering sustainable chemistry for a healthier planet and economy.
  • Houston-based Ententia, which offers purpose-built, generative AI for industry.
  • Houston-based GeoKiln Energy Innovation, which is developing a new way to produce clean hydrogen by accelerating natural geologic reactions in iron-rich rock formations using precision electrical heating.
  • Houston-based Timbergrove, which builds AI and IoT solutions that connect and optimize assets—boosting visibility, safety, and efficiency.
  • Houston-based dataVediK, which combines energy-domain expertise with advanced machine learning and intelligent automation to empower organizations to achieve operational excellence and accelerate their sustainability goals.
  • Houston-based Resonant Thermal Systems, which uses a resonant energy-transfer (RET) system to extract critical minerals from industrial and natural brines without using membranes or grid electricity.
  • Houston-based Torres Orbital Mining (TOM),which develops autonomous excavation systems for extreme environments on Earth and the moon, enabling safe, data-driven resource recovery and laying the groundwork for sustainable off-world industry.

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

More than 100 startups joined Greentown this year, according to an end-of-year reflection shared by Greentown CEO Georgina Campbell Flatter.

Flatter joined Greentown in the top leadership role in February 2025. She succeeded former CEO and president Kevin Knobloch, who stepped down in July 2024.

"I moved back to the United States in March 2025 after six years overseas—2,000 miles, three children, and one very patient husband later. Over these months, I’ve had the chance to hear from the entrepreneurs, industry leaders, investors, and partners who make this community thrive. What I’ve experienced has left me brimming with urgent optimism for the future we’re building together," she said in the release.

According to Flatter, Greentown alumni raised more than $2 billion this year and created more than 3,000 jobs.

"Greentown startups and ecosystem leaders—from Boston, Houston, and beyond—are showing that we can move further and faster together. That we don’t have to choose between more energy or lower emissions, or between increasing sustainability and boosting profit. I call this the power of 'and,'" Flatter added. "We’re working for energy and climate, innovation and scale, legacy industry and startups, prosperity for people and planet. The 'and' is where possibility expands."

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Houston's KBR tapped to provide tech for first SAF plant in Kazakhstan

clean deals

Houston-based engineering and technology firm KBR Inc. has been tapped to provide technology for Kazakhstan's first sustainable aviation fuel (SAF) production plant.

KazMunayGas-Aero LLP (KMG-Aero), a subsidiary of Kazakhstan’s national oil and gas company KazMunayGas, and KazFoodProducts awarded the contract to KBR for the project. The plant will use the alcohol-to-jet (AtJ) process for producing aviation fuel and aims to support President Kassym-Jomart Kemeluly Tokayev’s goal of boosting Kazakhstan's profile as a global aviation player, according to a news release from KBR.

"We are honored to support KMG-Aero and KFP in advancing the national commitment to reduce greenhouse gas emissions, recognizing the pivotal role of aviation decarbonization in achieving these strategic objectives,” Jay Ibrahim, president of KBR Sustainable Technology Solutions, said in the release.

KBR will provide its PureSAF technology and engineering design for the project. Invented and developed by Swedish Biofuels AB, the PureSAF tech will be used to convert alcohol-based feedstocks into SAF. The PureSAF Technology can process multiple feedstocks—like bioethanol, syngas, carbon dioxide and hydrogen—and convert them to SAF, diesel and gasoline, according to KBR.

"KBR’s PureSAF is a feed-flexible, bankable technology that is designed to deliver high SAF yields and supports the project across the full lifecycle,” Ibrahim added in the release. “We look forward to closely collaborating and supporting the successful execution of this landmark SAF project.”

Earlier this summer, KBR was also chosen to provide technology for what’s expected to be Asia's first commercial-scale ethanol-to-jet (SAF) plant. The plant has a planned production capacity of up to 100,000 tons of SAF per year.

In addition to the SAF projects, KBR also announced this month that it has been selected by ORNX Green Hydrogen to provide proprietary ammonia technologies for a low-cost green ammonia project in Morocco.

The commitments come as KBR shifts its focus solely toward sustainability technology and services. The company is in the process of spinning off its Mission Technology Solutions business, which KBR recently announced will be named Trinzic. The remaining company, "New KBR," will serve the ammonia and syngas, chemical and petrochemicals, clean refining and circular economy markets.

Army to build nuclear microreactors at 5 U.S. bases, including Texas

Nuclear News

The U.S. Army announced Wednesday that it plans to add nuclear microreactors at five military bases from New York to Texas as a reliable source of energy independent of the commercial electric grid.

The announcement comes as the Trump administration pushes hard to develop the next generation of nuclear power, including billions in loans for large nuclear reactors to meet skyrocketing power demand from data centers and a pilot program to boost advanced reactor designs and projects for military and civilian use. No nuclear microreactors are supplying power to the commercial electric grid in the United States today.

Five companies selected by the Army will be awarded up to $2.2 billion in total over five years to own, construct and operate the microreactors, if they hit set milestones along the way for their performance. The Army expects that more than 20 nuclear microreactors will be built and operated.

Army and industry officials say microreactors offer a resilient power source for critical infrastructure at military installations in case the grid fails. Reactors can run for years without refueling.

Army Secretary Dan Driscoll said the awards will accelerate the military’s ability “to deliver safe, reliable baseload power directly to our installations. We are building the energy resilience necessary to project combat power globally, without relying on potentially vulnerable external grids,” he said.

The grants are part of the Army's “Janus Program” launched last year to deliver next-generation nuclear energy. Officials hope to push nuclear development forward so that advanced reactor designs move beyond experiments and prototypes to provide power for years to come. This will be the “spear tip,” said Jeff Waksman, principal deputy assistant secretary of the Army for installations, energy and environment.

“That is the transition that we are trying to effect here,” he said on a call with reporters Wednesday. “These are not meant to be Army-specific designs.”

Critics of building more nuclear reactors say they’re too expensive and riskier than other energy sources. The Army program is using the military's “deep pockets to provide a hidden subsidy” to nuclear companies that can't find private-sector customers for their hypothetical and uneconomical reactors, said Alan J. Kuperman, associate professor at the Lyndon B. Johnson School of Public Affairs at the University of Texas at Austin and coordinator of the Nuclear Proliferation Prevention Project.

The reactors will be licensed by the Army, rather than the U.S. Nuclear Regulatory Commission, which licenses commercial nuclear reactors. Kuperman said it's “a dangerous scam on many levels.”

Waksman said these reactors will shut down safely in case of a failure, they're small and the Army wouldn't add them to installations without being certain they are safe. He said the Army is working on a deal with the Energy Department to remove radioactive waste, and there won't be any long-term storage on these installations.

The Army is working to align its regulatory processes as much as possible, Waksman said, so that companies won’t need major changes to their designs to be later licensed by the NRC. Along with federal funding, the Army expects billions of dollars in private capital investment.

Army leads the military’s adoption of nuclear energy

President Donald Trump signed executive orders in May 2025 to speed up the development of nuclear power. The Army was tasked with ensuring that an advanced reactor would start operating at a domestic military installation no later than Sept. 30, 2028. The Janus program is named for the ancient Roman god of transitions.

Officials know that delivering nuclear power to a military base will be a challenge, so they picked five companies in case one or more fail, Waksman said. The selected companies are: Antares Nuclear at Fort Bragg in North Carolina; BWXT at Fort Campbell in Kentucky; General Atomics Electromagnetic Systems at Fort Hood in Texas; Radiant Industries at Fort Benning in Georgia; and Westinghouse Government Services at Fort Drum in New York.

Senate Minority Leader Chuck Schumer asked the Army to select Fort Drum. The critical missions Fort Drum supports require secure power generation, the New York Democrat said.

The military installations will remain connected to the grid. The reactors would not completely power them. Each reactor will provide between 1 megawatt to 20 megawatts of power, depending on the company's design. Major bases use as much power as a small city. Antares and Radiant are planning to deliver their reactors in three-packs, Waksman said.

The Army now uses diesel as a primary backup for critical infrastructure. But in a conflict, Waksman said, the Army may not be able to move fossil fuels easily wherever it needs them.

“That makes nuclear energy just a natural game changer,” he said. “It makes sense for the Army to take the lead here.”

A reactor at Fort Belvoir in Virginia, completed in 1957, was the first nuclear power reactor to provide electricity to a commercial power grid in the United States for an extended period, according to the U.S. Army Corps of Engineers.

Companies say this will accelerate US nuclear development

California-based Antares reached a crucial milestone under the U.S. pilot program that could allow it to produce electricity at Idaho National Lab next year. The company said the Army's announcement extends its momentum. Westinghouse Government Services said it’s proud to support the Army’s efforts to strengthen energy security and innovate.

Tori Shivanandan, president and chief operating officer of California-based Radiant, said the Army’s $750 million award “shows confidence in Radiant’s product and ability to manufacture, deploy and safely operate nuclear microreactors for the American military.” The Janus program “will build a stronger and more resilient America,” she said.

General Atomics Electromagnetic Systems said its reactor is designed to operate in remote, off-grid and extreme environments for 40 years. It said it will draw on more than 70 years of nuclear expertise to provide safe, dependable and independent power for the military.

Rex Geveden, BWXT's president and chief executive officer, said, “As we commence work on the Janus program, we are delivering the nation’s most credible and reliable path to deployable nuclear power.”

Energy giant Shell lists Houston HQ for sale for $325 million

asset offload

Energy giant Shell has put its U.S. headquarters in Houston’s Energy Corridor on the market and is exploring the sale of its U.S. chemical business.

Green Street News reported Shell just listed its longtime Energy Corridor campus at 150 N. Dairy Ashford Road. The asking price is $325 million, The Real Deal reported. Shell plans to lease back half of the nearly 1.5 million-square-foot Woodcreek campus for 15 years.

A sale-leaseback deal could transform the 43.6-acre campus into a multitenant hub, CoStar News reported.

“Houston is a critical hub for Shell globally and the headquarters of our U.S. businesses,” a Shell spokesperson told the Houston Business Journal. “We remain committed to Houston and are evaluating opportunities to optimize our Woodcreek campus as part of our ongoing review of workplace needs while maintaining a strong presence in the city.”

Shell occupied its first building at the West Houston campus in 1980. The company employs more than 6,000 people in Texas.

Shell is one of the highest-profile businesses occupying space in the Energy Corridor. It’s home to 67,000 workers, more than 27 million square feet of office and mixed-use space, and 3.8 million square feet of retail and restaurant space.

Shell considers $8B sale of chemical business

As the company seeks to unload its Woodcreek campus, The Financial Times reported Shell is looking into selling its U.S. chemical business. The price tag: $8 billion.

Potential buyers include Spring-based ExxonMobil and Houston-based LyondellBasell.

Shell operates four chemical plants in Texas, Louisiana and Pennsylvania, producing an array of chemicals for use in plastics, detergents and pharmaceuticals.

Shell CEO Wael Sawan said last year that the company had spent $45 billion in capital “that is underperforming for us,” split between its chemical business and renewable energy arm.

Shell also agreed to sell its solar and wind power business in India this summer. Read more here.