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

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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Houston startup wins Space Force contract to advance quantum energy generator

quantum contract

Houston-based quantum energy technology startup Casimir Inc. has been awarded an STTR Phase I contract from the U.S. Space Force's SpaceWERX to support the development of the company's solid-state generator for potential use by the Department of the Air Force.

SpaceWERX is the innovation arm of the U.S. Space Force and a division within AFWERX, the incubator and innovation arm of the United States Department of the Air Force. The Air Force Research Laboratory and SpaceWERX, along with many other government agencies, help support innovation through the Small Business Innovation Research (SBIR) and Small Business Technology Transfer (STTR) grants and contracts.

As part of the new contract, Casimir will work to refine a fully independent generator. Casimir’s solid-state power technology could support national security missions by providing reliable power even in difficult-to-service environments.

In May, Casimir emerged from stealth, netting a $12 million seed round to commercialize its quantum energy chip. The semiconductor chips can generate power from quantum vacuum fields without the need for batteries or charging. The company aims to include the chips in large-scale energy systems that can power homes, commercial infrastructure and electric vehicles.

“This STTR funds some analysis work to address our proposed scaling approach of making our chips multi-layer to increase aggregate power,” Harold “Sonny” White, founder and CEO of Casimir, tells Energy Capital.

White adds that the company will work with Texas A&M to develop chip planarization techniques to support Casimir’s plans to scale. Additionally, White says the company is working with the U.S. Space Force to explore more applications for its technology.

“Casimir’s technology brings a new capability to the market in the form of our persistent power chips,” White adds. “This approach will be relevant to ultra-low-power electronics, and with the scaling approach we are developing, connected with the STTR work, will eventually be relevant to consumer electronics and beyond.”

Casimir has previously reported that it plans to commercialize its first-generation MicroSparc chip by 2028. The chips are expected to power devices for years without the need for replacements.

The total funding for this project has not yet been disclosed.

Houston clean energy tax compliance platform tops the Inc. 5000 in 2026

Top of the List

Houston-based Empact Technologies has ridden the clean energy wave to the Inc. 5000’s 30 fastest-growing private companies.

With three-year revenue growth of 8,275 percent, the clean energy tax credit compliance management platform appears at No. 27 on this year’s Inc. 5000 list. The 2026 list ranks private companies based on percentage revenue growth from 2022 to 2025.

Empact Technologies, also ranks as the No. 2 fastest-growing company in Houston and the No. 4 fastest-growing company in Texas.

Originally founded by Charles Dauber in 2012, Empact Technologies relaunched in 2023 as a purpose-built tool for clean energy tax credit compliance, following the creation of the Inflation Reduction Act, the largest clean energy investment incentive in U.S. history.

It provides a platform for clean energy developers, investors, and contractors, and combines its NexusIQ AI-native compliance platform with a dedicated team of technical and regulatory experts to ensure ongoing compliance and documentation.

Empact Technologies is joined by six other Houston-area companies in the top 250 of this year's Inc. 5000, including one that made the top 10.

Here are the six other Houston-area companies that claimed spots in the top 250 on the Inc. 5000 list. Each company name is followed by its ranking, headquarters city, and three-year growth rate.

  • No. 6 Equipe Realty, 23,210 percent
  • No. 60 Action1, 4,512 percent
  • No 75 Signs By G, 3,684 percent
  • No. 79 The ’Pause Life, 3,469 percent (Galveston)
  • No. 110 Turtlebox Audio, 2,576 percent
  • No. 178 Dahnani Private Equity Group, 1,904 percent (Stafford)
Empact and fellow honorees will be recognized Oct. 14-16 at the 2026 Inc. 5000 Conference & Gala in Dallas.

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A version of this article first appeared on InnovationMap.com.

Sage Geosystems brings South Texas geothermal plant online

powering up

Houston-based Sage Geosystems, a provider of geothermal power, has begun full operations at its South Texas facility for the San Miguel Electric Cooperative.

Sage says the plant was recently “placed in service,” according to a news release. This means it’s fully built and tested, and ready to generate and supply electricity to the grid.

Since selling its first electricity in Q2 of this year, the facility has been operating for more than four months to evaluate aspects like efficiency and water management. Sage relied on its GeoTwin modeling tool to carry out some of the testing.

The testing demonstrates Sage’s proprietary approach to geothermal power “overcomes one of the industry’s most persistent challenges, high water losses in engineered reservoirs, while delivering the consistent performance required to scale next-generation geothermal,” co-founder and CEO Cindy Taff said in the release.

Sage says the South Texas facility will serve as a model for future projects, including one in Nevada. The Nevada facility will use Sage’s proprietary technology to extract geothermal heat from hot dry rock, creating a reliable, affordable source of carbon-free power.

During the testing period, water losses amounted to less than 10 percent. This low rate indicates most water remains in the system, enabling Sage to capture more usable energy, boost power production and improve the project’s finances, the company says.

“Commercial geothermal isn’t just about creating a reservoir. It’s about creating one whose performance can be engineered, predicted, and consistent,” Lev Ring, the company’s co-founder, president and chief technology officer, said in the release.

Since being founded in 2020, Sage has raised $159 million in outside funding. This includes a more than $97 million Series B round co-led by Ormat Technologies and Carbon Direct Capital.

Two years ago, Sage announced a deal with Meta Platforms, the parent company of Facebook and Instagram, to supply up to 150 megawatts of geothermal power to Meta data centers.