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.

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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.