Amperon, Hertha Metals and Vaulted Deep were named to this year's Global Cleantech 100 list. Photo via Getty Images

Three Houston-area companies—Amperon, Hertha Metals and Vaulted Deep—appear on this year’s Global Cleantech 100 list.

The unranked list, generated by market intelligence and advisory firm Cleantech Group, identifies the 100 privately held companies around the world that are most likely to make a significant impact in the cleantech market over the next five to 10 years.

For the 2026 list, Cleantech Group received more than 24,000 Global Cleantech 100 nominations from nearly 60 countries. Cleantech Group scored those companies and narrowed the contenders to 264. An expert panel reviewed those nominees, and the list was whittled down to the 100 winners.

Here’s a rundown of the three Houston-area honorees:

Amperon

Founded in 2018 by Sean Kelly and Abe Stanway, Houston-based Amperon offers an AI-enabled energy forecasting and analytics platform designed to help stabilize electric grids. Amperon received undisclosed amounts of venture capital from National Grid Partners and Tokyo Gas Co. Ltd. last year and announced a recent investment from Samsung Ventures earlier this month.

Hertha Metals

Founded in 2022 by Laureen Meroueh, Conroe-based Hertha Metals provides a single-step process for producing sustainable steel. Last year, the company emerged from stealth mode and raised more than $17 million in venture capital.

Vaulted Deep

Vaulted Deep’s technology injects excess organic waste underground to remove carbon dioxide from the atmosphere. Julia Reichelstein and Omar Abou-Sayed founded the Houston-based company in 2023. Last year, the startup raised $32.3 million in venture capital. Also in 2025, Vaulted Deep signed a 12-year deal with software giant Microsoft to remove up to 4.9 million metric tons of carbon dioxide from the environment.

Vaulted Deep also made the list last year, along with Houston-based Syzygy Plasmonics and Fervo Energy. Fervo was also named the 2025 North American Company of the Year by Cleantech Group.

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Rice University spinouts named among 50 top cleantech companies to watch

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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.