Maritime

SeaO₂: Turning the ocean into a carbon-removal engine thanks to BlueInvest

Published

4 months ago

February 24, 2026

SeaO₂ is a Dutch company pioneering a new method to remove carbon dioxide (CO₂) - by treating seawater and returning 'decarbonised' water to the ocean. This innovative process allows the ocean to absorb CO₂ from the air again, and can help counter ocean acidification at a local level. Thanks to EU support, the company received tailored coaching on investor engagement and strategic planning.

“The oceans absorbs over 25% of human CO₂ emissions and hold vastly more carbon than air, so it is a very strong ally in carbon removal,” said Zamin Syed, Founder’s Associate at SeaO₂. But as emissions continue rising, the ocean's ability to absorb CO₂ is under pressure.

Founded in 2021 as a spin-off from TU Delft, SeaO₂ has grown into a dynamic team of 12 specialists in chemistry, oceanography, engineering, and business. Through direct ocean capture (DOC) technology, SeaO₂ offers a scalable carbon-removal option to help achieve net-zero emissions. It also explores ways to utilise captured CO₂, potentially benefiting sectors like sustainable fuels and beverages.

SeaO₂’s strategy includes three key aspects

developing DOC technology
making carbon removals profitable by selling carbon-dioxide removal (CDR) credits to businesses
supplying captured CO₂ to industrial clients

Beyond the engineering challenge, SeaO₂ aims to fill a gap in Europe’s climate toolkit with effective ocean-based carbon removal.

As Zamin explains: "Carbon removal as a whole has been growing, especially in the EU. We are leaders in the direct ocean capture space. Our method is increasingly being mentioned in EU communications, and that gives our technology a real stamp of approval.”

How this technology works

SeaO₂ extracts CO₂ from seawater using an electrochemical process. By lowering the CO₂ content in a flow of seawater and returning that treated water to the ocean’s surface layer, the ocean can re-absorb CO₂ from the atmosphere—helping reduce atmospheric CO₂ while supporting ocean balance.

In principle, this method can be deployed along coastlines worldwide. However, SeaO₂ prefers working with existing coastal infrastructure, like desalination plants, to cut energy needs and operating costs. Future site prospects include areas in Norway and Canada with good ocean conditions and access to renewable energy.

**SeaO₂’s containerized pilot, Project Swell, with a carbon removal capacity of 25 tCO₂/year at the Afsluitdijk in the Netherlands.©SeaO₂**

From lab to market

SeaO₂ proved its technology in 2023 with Project Ripple, capturing its first batch of CO₂ and permanently storing it through mineralisation. Project Swell, now operating in the Netherlands, will run under real marine conditions, paving the way for Project Breaker, planned for 2028. Project Breaker will also introduce a commercial component, as it is designed to generate and deliver carbon credits. To fund this phase, SeaO₂ is preparing a Series A of around €12 million for early 2027. SeaO₂ has already pre-sold carbon-removal credits to early buyers, including Klarna, with delivery set for once operations begin.

**SeaO₂’s tech team closely monitoring all parameters throughout each commissioning step of Project Swell.© SeaO₂**

BlueInvest in action

SeaO₂ joined the BlueInvest Readiness Assistance programme in 2024, receiving tailored support on investor engagement and strategic planning. This support was useful in shaping SeaO₂’s complex innovation into investor-friendly proposals. Participation in BlueInvest Day expanded SeaO₂’s network in the ocean-tech and investment communities.

As Zamin reflects: “For us, BlueInvest is also about community. It was inspiring to meet other teams working in ocean technology and to realise we’re not alone in this field. It was also very valuable to connect with organisations across the blue economy, including representatives from the European Commission, and to see first-hand how much is happening at European level.”

About BlueInvest

BlueInvest is the EU's innovation and investment platform for the blue economy, offering business coaching, fundraising support, and networking opportunities for ocean technology companies.

Interested individuals can register with the BlueInvest Community to explore programme features and opportunities or contact [email protected].