Five companies have joined Greentown Labs Houston, specializing in various "green" applications, from converting plastic waste into sustainable materials to developing energy-storage solutions. Photo courtesy Greentown Labs.

Greentown Labs announced that it added five startups to its Houston community in Q1 of 2025.

The companies are among a group of 19 that joined the climatetech incubator, which is co-located in Houston and Boston, in the same time period. The companies that joined the Houston-based lab specialize in a number of "green" applications, from converting plastic waste into sustainable materials to developing energy-storage solutions.

The new Houston members include:

  • Concept Loop, a project of Pakistan-based Innova8e Inc., aims to repurpose post-industrial and post-consumer plastic waste into sustainable building materials.
  • GeoFuels, a Sugar Land-based company that produces hydrogen by using baseload geothermal power and methane pyrolysis.
  • PLASENE, a Houston-based company with an innovative platform that converts plastic waste into liquid fuel and low-carbon hydrogen through its proprietary catalysts and modular, scalable, pre-engineered units platform. The company was named to Greentown's ACCEL Year 3 cohort earlier this year.
  • RepAir Carbon, an Israeli company with a fully electric, zero-heat carbon-removal technology that consumes minimal energy, operates without liquids or solvents, and produces no hazardous materials or waste.
  • RotorVault from Pasadena, California, is commercializing energy-storage and load-following solutions that are containerized, modular, and field-deployable systems built on flywheel technology.

Fourteen other companies will join Greentown Boston's incubator. See the full list here.

PLASENE and five other new members—Thola, Respire Energy, Andros Innovations, FAST Metals and Tato Labs—join Greentown Labs through its most recent Advancing Climatetech and Clean Energy Leaders Program, or ACCEL, cohort. ACCEL, which works to advance BIPOC-led startups in the climatetech space, announced its third cohort last month.

From potato-starch-based bioplastics startups to companies developing carbon-coated silicon anodes, here's who's joining Greentown Labs and Browning the Green Space's ACCEL program. Photo via browningthegreenspace.org

2 Houston startups join Greentown Labs' BIPOC-led accelerator program

seeing green

Greentown Labs and Browning the Green Space announced the newest cohort for its Advancing Climatetech and Clean Energy Leaders Program, or ACCEL, which works to advance BIPOC-led startups in the climatetech space.

Two Houston companies and one from Austin are among the eight startups to be named to the 2025 group.

“The startups selected for the third ACCEL cohort represent a phenomenal range of energy and climatetech innovations, which underscores our belief that everyone and many solutions must play a role in our community’s collective decarbonization efforts,” Georgina Campbell Flatter, Greentown’s new CEO, said in a release. “We’re proud to welcome these entrepreneurs to our community and eager to see all they’ll achieve throughout the program and beyond!”

Each of the early-stage startups within the cohort will receive $25,000 in non-dilutive grant funding and participate in the year-long program focused on product and technology development, market development, fundraising and management, and team development, according to Greentown. The curriculum is led by VentureWell, a nonprofit with expertise in venture development in climatetech.

The Houston companies include:

  • Carbonext, founded by Olanrewaju Tanimola. The company is leveraging its proprietary, off-the-shelf 3D-graphene technology to develop integrated solutions with carbon-coated silicon anodes to address challenges in the graphite ecosystem, as well as lithium-battery anodes.
  • PLASENE, founded by Sohel Shaikh, Alper Gulludag and Romolo Raciti. The company offers an innovative platform that converts plastic waste into liquid fuel and low-carbon hydrogen through its proprietary catalysts and modular, scalable, pre-engineered units

The remaining six companies are:

  • Inductive Robotics, founded in Austin by Madhav Ayyagari and David Alspaugh. The startup deploys autonomous robots that deliver EV charging directly to parked vehicles in commercial parking facilities, using a subscription-based model.
  • Andros Innovations, founded in Cambridge, Massachusetts by Laron Burrows. The startup has developed a reactor that produces ammonia more cheaply, cleanly and safely than traditional methods do.
  • FAST Metals, founded in Worcester, Massachusetts by Sumedh Gostu and Anthony Staley. It has developed a hydrometallurgical-recovery process capable of extracting iron, aluminum, scandium, titanium, and other rare-earth elements from industrial tailings.
  • Respire Energy, founded in Boston by Dave Hsu, Xiaowei Teng, and Candy Wong. The energy storage startup has developed a safe, low-cost, and long-duration metal-air battery designed for microgrids.
  • Tato Labs, founded in Brooklyn by Mecca McDonald and Mia Dunn. It is developing scalable, innovative, bioplastic products and packaging solutions that leverage potato starch, protect and preserve the natural ecosystem, and minimize plastic waste.
  • Thola, founded in Portland, Maine, by Nneile Nkholise and Lerato Takana. The company provides an on-demand marketplace for commercial-building sustainability and safety management, with a mission to decarbonize old buildings.

ACCEL is supported by the Massachusetts Clean Energy Center (MassCEC), Shell, Equinor, the Growth Capital Division of MassDevelopment, Microsoft and the Barr Foundation.

The accelerator has supported 13 early-stage startups since it was founded in 2023, resulting in $325,000 in grant funding. Houston companies have been represented in each cohort. Click here to see the 2024 cohort and here to see the inaugural 2023 cohort.

Ad Placement 300x100
Ad Placement 300x600

CultureMap Emails are Awesome

Rice University spinouts named among 50 top cleantech companies to watch

green team

Two Rice University spinouts, Coflux Purification and DexMat, appear on a new list of the world’s 50 cleantech companies to watch.

Cleantech Group’s 2026 Cleantech 50 to Watch list recognizes early-stage companies “creating groundbreaking solutions to address some of the world’s most pressing environmental and sustainability challenges.”

Cleantech Group, a market research, consulting, and events company, selects the 50 honorees based on insights from analysts and early-stage innovators, along with public nominations.

Destroying “forever chemicals”

Coflux, founded in 2024, offers an onsite treatment system that captures and destroys manufactured “forever chemicals”—per- and polyfluoroalkyl substances—in water and wastewater. It’s a member of Greentown Houston.

Alec Ajnsztajn, CEO; Jeremy Daum, chief technology officer; and Dana Vazquez, chief commercial officer, co-founded Coflux. Ajnsztajn and Daum earned doctoral degrees from Rice, and Vazquez earned an MBA from the university.

Coflux spun out of Rice labs directed by professors Rafael Verduzco and Pulickel Ajayan.

Last year, Coflux received a $175,000 grant from the U.S. Food and Drug Administration’s National Institute of Food and Agriculture. The startup has also raised more than $500,000 in non-dilutive funding, including $80,000 awarded in 2024 by Rice’s One Small Step Grant program.

Promoting an alternative to copper

DexMat, founded in 2015, produces carbon nanotube products such as fibers, yarns, cables, and fabric. The company’s products address demand for materials that can reduce carbon emissions, according to CB Insights.

Its main product, Galvorn, is a copper alternative made of carbon nanotube fibers. CB Insights says Galvorn is engineered to be lighter and stronger than traditional conductive materials like carbon and steel. It’s used in industries such as energy, aerospace, defense, automotive, consumer electronics, and health care.

DexMat emerged from Matteo Pasquali’s Carbon Lab at Rice. Pasquali, co-founder of DexMat, co-invented the company’s technology with the late Nobel Prize-winning chemist Rick Smalley. Smalley was a professor of chemistry, physics, and astronomy at Rice.

Pasquali is a professor of chemical and biomolecular engineering, chemistry, materials science, and nanoengineering at Rice. He co-founded DexMat with Rice graduate Dmitri Tsentalovich, the company’s director of product innovation.

Earlier this year, DexMat raised $5 million in seed funding from Non Sibi Ventures, Governance Partners, Tailwind Futures, BetterWay, Capital Factory, and other investors. The company also secured $3 million in non-dilutive funding.

In 2023, DexMat raised $3 million in a pre-seed round led by Shell Ventures.

TotalEnergies expands solar joint venture with $1.2B portfolio in Texas, Ohio

solar expansion

TotalEnergies, a French company whose U.S. headquarters is in Houston, announced this month that it is expanding its renewable energy joint venture with New York-based investment firm KKR by adding 700 megawatts of utility-scale solar projects.

The deal will add three utility-scale solar assets in Texas and Ohio, which are expected to reach commercial operation by Q1 2027, according to a news release from the company. The portfolio is valued at $1.2 billion.

The 50/50 joint venture between TotalEnergies and KKR currently holds 1.4 gigawatts of renewable energy and will grow to 2.1 gigawatts.

The new deal is expected to close this year. Once completed, TotalEnergies will operate the assets. The electricity generated from the solar projects will be sold to third parties, the company reports.

The companies originally formed the joint venture about a year ago when TotalEnergies sold KKR a 50 percent stake in a North American solar portfolio valued at $1.25 billion. The deal originally included six utility-scale solar assets, primarily located in the U.S.

“TotalEnergies is a renewable energy industry leader globally, and we are thrilled to establish this joint venture with the TotalEnergies team to support their renewables business," Cecilio Velasco, managing director KKR, said in a release last year. “We have long been investors in renewables through our infrastructure platform, having committed more than $23 billion to date in energy transition investments. TotalEnergies’ North American solar portfolio is a great fit for us, representing high-quality renewable energy assets with long term contracts.”

TotalEnergies reports that by June 2026 it held more than 37 gigawatts of gross renewable power generation capacity. It aims to achieve over 100 terawatt-hours of net electricity production by 2030.

The company signed a major power purchase agreement with Google earlier this year. Through the deal, TotalEnergies will supply the tech giant with 1 gigawatt of solar power for its data centers in Texas over a 15-year span.

However, the company also recently redirected nearly $1 billion in capital away from wind energy projects and "decided to renounce offshore wind development in the United States." Read more here.