Carbon Clean develops carbon capture technology for customers such as cement producers, steelmakers, refineries, and waste-to-energy plants.

Abu Dhabi National Oil Co. (ADNOC), the state-owned oil company of the United Arab Emirates, has chosen technology from United Kingdom-based company Carbon Clean for a carbon capture project in Abu Dhabi. Carbon Clean’s U.S. headquarters is in Houston.

Carbon Clean’s modular CycloneCC technology will be used for a carbon capture project at a Fertiglobe nitrogen fertilizer plant. Fertiglobe is a joint venture between ADNOC and OCI Global, a Netherlands-based chemical company.

“This project is hugely significant given it’s the first industrial deployment of our award-winning CycloneCC technology anywhere in the world,” says Aniruddha Sharma, chairman and CEO of Carbon Clean. “We are moving a step closer to achieving full commercialization of this modular solution, which will play a vital role in decarbonizing heavy industries and achieving net-zero targets.”

Carbon Clean develops carbon capture technology for customers such as cement producers, steelmakers, refineries, and waste-to-energy plants. The company bills its offering as the “world’s smallest industrial carbon capture technology.”

CycloneCC can reduce the cost of carbon capture by as much as 50 percent with a footprint that’s 50 percent smaller than traditional carbon capture units, according to Carbon Clean. The startup’s unit arrives ready to install and can be up and running in eight weeks.

The company established its Houston outpost earlier this year.

In 2022, Houston-based Chevron New Energies led the company’s $150 million series C round. Other contributors to the round were CEMEX Ventures, Marubeni, WAVE Equity Partners, AXA IM Alts, Samsung Ventures, Saudi Aramco Energy Ventures, and TC Energy. To date, Carbon Clean has raised $195 million.

Here's what energy transition companies stood out to Rice Alliance's experts. Photo via Rice Alliance

Investors name 10 most-promising energy tech companies at Houston conference

startups to know

At the 20th annual Energy Tech Venture Forum presented by Rice Alliance for technology and Entrepreneurship, 11 startups scored recognition from the event's investors who evaluated over 90 early-stage energy transition companies.

"The selection process was both exhilarating and challenging given the incredible ideas we've seen today," says Jason Sidhu, director of information services business engagement at TC Energy, who announced the top companies. "I want to extend my gratitude to every company that participate din this year's Energy Tech Venture Forum. Your commitment to solving energy problems and pursuing ambitions ideas is truly commendable."

In addition to the top 10 most-promising companies, the event's attendees decided the people's choice pick out of the 50 or so pitching companies. The winner of that recognition was Calgary, Alberta-based Galatea Technologies, which has created a tech platform to enhance workflows for operational, financial, and environmental performance.

The top companies, according to the Rice Alliance experts and investors, were:

  • Circular economy startup, Polystyvert. Based in Montreal, the company has created a unique dissolution recycling process that creates a material that can contribute to cutting carbon emissions by up to 90 percent.
  • United Kingdom-based Mirico provides a tracking technology to its customers to measure climate gases (like methane, carbon dioxide, nitrous oxide, and ammonia), across areas up to half a square mile and in all conditions.
  • Protein Evolution, from New Haven, Connecticut, taps into a combination of green chemistry and enzyme technology to break down synthetic polymers.
  • Another Canadian company, Ayrton Energy, based in Calgary, created a liquid organic H2 carrier (LOHC) storage technology presents an opportunity for large, scalable and efficient transport of H2 over long distances.
  • Also representing New Haven, Connecticut, Carbon Loop is on a mission to make carbon capture and conversion scalable through carbon dioxide electrolysis using a proprietary catalyst to convert captured carbon dioxide into methanol.d
  • Based in London, Mobilus Labs has designed a new way for frontline communication with an in-helmet hardware and software solution. software solution designed for the frontline workforce.
  • 1s1 Energy, based in California, is working on producing low-cost green hydrogen by creating new materials to unlock unprecedented electrolyzer efficiency, durability, and more.
  • From Skokie, Illinois, Numat is specializing in solutions within Metal-organic framework (MOF) research to enhance the process of separating the hazardous chemicals negatively impacting human health and the environment.
  • Mantel, headquartered in Cambridge, Massachusetts, created a molten borate technology to capture CO2 in a new and efficient way.
  • The lone Houston-based company, Mars Materials is working to produce acrylonitrile using CO2 and biomass to enable decarbonization applications in carbon fiber and wastewater treatment.

Ten companies from around the world were named as most promising. Photo courtesy of Rice

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Houston maritime startup raises $43M to electrify cargo vessels

A Houston-based maritime technology company that is working to reduce emissions in the cargo and shipping industry has raised VC funding and opened a new Houston headquarters.

Fleetzero announced that it closed a $43 million Series A financing round this month led by Obvious Ventures with participation from Maersk Growth, Breakthrough Energy Ventures, 8090 Industries, Y Combinator, Shorewind, Benson Capital and others. The funding will go toward expanding manufacturing of its Leviathan hybrid and electric marine propulsion system, according to a news release.

The technology is optimized for high-energy and zero-emission operation of large vessels. It uses EV technology but is built for maritime environments and can be used on new or existing ships with hybrid or all-electric functions, according to Fleetzero's website. The propulsion system was retrofitted and tested on Fleetzero’s test ship, the Pacific Joule, and has been deployed globally on commercial vessels.

Fleetzero is also developing unmanned cargo vessel technology.

"Fleetzero is making robotic ships a reality today. The team is moving us from dirty, dangerous, and expensive to clean, safe, and cost-effective. It's like watching the future today," Andrew Beebe, managing director at Obvious Ventures, said in the news release. "We backed the team because they are mariners and engineers, know the industry deeply, and are scaling with real ships and customers, not just renderings."

Fleetzero also announced that it has opened a new manufacturing and research and development facility, which will serve as the company's new headquarters. The facility features a marine robotics and autonomy lab, a marine propulsion R&D center and a production line with a capacity of 300 megawatt-hours per year. The company reports that it plans to increase production to three gigawatt-hours per year over the next five years.

"Houston has the people who know how to build and operate big hardware–ships, rigs, refineries and power systems," Mike Carter, co-founder and COO of Fleetzero, added in the release. "We're pairing that industrial DNA with modern batteries, autonomy, and software to bring back shipbuilding to the U.S."

Shell partners with UK-based co. for hydrogen electrolyzer pilot

ultra-efficient electrolyzer

Shell Global Solutions International, a subsidiary of Shell, which maintains its U.S. headquarters in Houston, has signed a collaboration agreement with London-based Supercritical Solutions to advance Supercritical’s ultra-efficient hydrogen electrolyzer technology toward a field pilot demonstration.

In the deal, the companies will collaborate on a paid technology feasibility study that will support the evaluation and planning of the pilot demonstration, according to a news release. Supercritical Solutions’ technology aims to deliver high-efficiency renewable hydrogen at a lower cost for the industrial hydrogen market.

"Signing this collaboration agreement with Shell is a major milestone for Supercritical Solutions and an important step on our commercialisation journey,” Luke Tan, co-founder of Supercritical, said in the news release. “We are directly addressing the cost and complexity barriers facing the renewable hydrogen market. We are excited to move forward with a company like Shell, whose global leadership has been proven to accelerate innovative technologies to market.”

Supercritical’s hydrogen electrolyser technology can operate at high temperatures and pressures of up to 220 bar without the need for an external hydrogen compressor, rare-earth materials or easily degradable membranes. The technology removes the typical compression step in the process while delivering hydrogen at industry standards. It requires significantly less energy than many traditional electrolyzers and is more cost-efficient.

This recent investment builds on an ongoing relationship between Shell and Supercritical. Supercritical was founded in 2020 and was runner-up in Shell’s New Energy Challenge, which helps startups and scaleups develop sustainable technologies, in 2021. Shell Ventures then invested in Supercritical’s Series A funding round in 2024 with Toyota Ventures.

3 Houston-area companies named to Global Cleantech 100

Energized

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.