Brineworks, a climate-tech startup, just raised $5.5 million in seed funding in hopes of bringing a carbon-neutral alternative fuel to market for airlines and cargo ships by the end of 2026.
The Amsterdam-based startup claims it has rapidly developed a low-cost, patented technology over the past two years that uses seawater to pull CO2 from seawater, which creates significant amounts of hydrogen in the process. The system, known as electrolysis, produces hydrogen and CO2 that can be stored and sold as sustainable aviation fuels (SAF) and e-methanol for shipping. CEO Gudfinnur Sveinsson told Fortune in an exclusive interview that the new funding will be used to scale the system to pilot level, targeting a commercial-ready product by the end of next year.
“What this (funding) is allowing us to do is really to take our technology to the next stage,” Sveinsson said. “Getting to those very low costs in direct air capture will be key to both extract historical emissions out of the atmosphere and store them permanently, but also to scale up these low-cost energy mediums like e-fuels for shipping and aviation.”
Sveinsson said Brineworks’ technology is designed for intermittent operation, allowing it only to run on the “cheapest electricity sources available”: solar and wind. This helps drive down costs and differentiates his business model from competitors, he said.
Brineworks has partners in North America, Europe, and Asia, and is looking to map out projects in Northern Africa and the Middle East “to start demonstrating the technology at larger scales, showcasing that it works in different climates, which is very important for the scalability,” Sveinsson said.
The startup recently received a $1.8 million grant in funding from the European Innovation Council’s Accelerator program, which invests in startups and SMEs.
The company was founded in 2023 by Sveinsson, a Columbia University graduate with a background in climate policy and innovation, and Joseph Perryman, an electrochemist who completed his postdoctoral research at Stanford University. Perryman now works as CTO of Brineworks.
The seed funding round was led by SeaX Ventures, a San Francisco-based global venture-capital firm, which just launched a climate-focused fund.
“I think they have the breakthrough technologies,” Kid Parchariyanon, founder and managing partner at SeaX Ventures, told Fortune.
SeaX Ventures often invests in early-stage companies, including Bitkub, one of Southeast Asia’s largest crypto exchanges, and Type One Energy, a fusion-energy company that has been valued between $214 and $321 million following major funding rounds in 2025.
Global investments for renewable energy development had a record first half of 2025, reaching $386 billion and up 10% from the year prior, according to BloombergNEF’s Renewable Energy Tracker. This growth has been largely spurred by global offshore wind and small-scale solar. The International Energy Agency’s World Energy Investment report estimates capital flows to the energy sector are set to rise to $3.3 trillion this year, with renewable energy investment doubling that of investments towards fossil fuels. Low-emissions fuel will account for $40 billion, the report says.
As renewable energy investment grows, companies are looking to differentiate themselves from competition.
“We envisioned the electrolyzer of the future—and now it’s here,” Perryman said in a company release.
