Startups STAX Engineering and Seabound completed a successful demonstration, proving viable comprehensive emissions and carbon capture for the global maritime industry
STAX Engineering, a pioneer in maritime emissions capture and control based in California, and Seabound, a UK-headquartered leader in onboard carbon capture, successfully demonstrated a first-of-its-kind fully integrated emissions and carbon capture solution during an event held Wednesday at the Port of Long Beach, California. The end-to-end modular solution has now cleared the final trial, readying to explore an upcoming deployment with the Associated British Ports (ABP). By tackling both criteria pollutants and greenhouse gases, maritime operators worldwide now have an immediate, practical path to meet tightening environmental regulations and decarbonization requirements.
During a Carbon Capture Showcase in the Port of Long Beach, the two companies showcased their combined emissions-reduction technologies in action. Connected together atop a STAX barge, the combined system serviced an at-berth roll-on roll-off (RoRo) vessel from Wallenius Wilhelmsen (WWL), filtering out harmful pollutants including particulate matter (PM) and nitrogen oxide (NOx) and capturing carbon dioxide directly from the vessel’s exhaust. Event attendees included US industry leaders and port stakeholders as well as British Consul General Paul Rennie and Riley Mannon, senior trade and investment officer of clean energy.
This breakthrough marks a significant milestone in port emissions reduction, at a time when regulations are addressing the billions of tons of annual carbon emission from the industry. Shippers across the world are under pressure to meet the International Maritime Organization’s mandate to cut carbon emissions by 20% by 2030 and work toward regional goals like the UK’s recently updated greenhouse gas reduction goals. With few viable solutions available for emissions reductions in ports, STAX and Seabound are providing the first comprehensive, cost-effective emissions solution for the maritime industry, without requiring vessels or ports to undergo retrofits and costly structural changes.
“Today marks a landmark moment in our journey toward a zero-emissions future, and it’s just the beginning of a global maritime emissions solution,” said STAX CEO Mike Walker. “As we expand our carbon capture capabilities across the fleet, our inaugural partnership with Seabound has been instrumental and we look forward to partnering again with ABP in the Port of Southampton. The growing demand from port leaders and our customers reinforces our commitment to leading the maritime sector toward a more sustainable future.”
“Our partnership demonstrates that effective, scalable emissions solutions are a reality that we can implement now,” said Alisha Fredriksson, co-founder and CEO of Seabound. “Our collaboration with STAX proves that by leveraging innovative onboard carbon capture, we can make a tangible difference on a global scale and provide the maritime industry with the tools vital for a sustainable future.”
The Carbon Capture Showcase marked the culmination of months spent trialing the system where Fredriksson, Walker, and STAX Founder and CTO Bob Sharp presented the integrated system during a live demonstration. Funded by CARB and South Coast Air Quality Management District (AQMD) as part of their Advanced Technology Demonstration and Pilot Projects, the trials began March 2025 and had three iterations. Each trial serviced an existing STAX customer, including WWL and NYK Line. All results were independently verified by Yorke Engineering, an environmental consultancy.
STAX and Seabound will continue their partnership in the UK’s Port of Southampton. In March 2025, ABP welcomed STAX and Seabound into its Energy Ventures Accelerator, a program designed to explore clean energy hardware startups to clean up ABP’s ports nationwide as it works toward Net Zero by 2040.
“The partnership between STAX Engineering and Seabound demonstrates the strength of UK’s role as a world leader in cutting-edge maritime innovation,” said His Majesty’s Consul General Paul J. G. Rennie, OBE. “This collaboration is a powerful example of how UK-US commercial partnerships are shaping the future of global industries by delivering innovative tech that not only transforms port operations but also supports cleaner and more resilient supply chains world-wide.”
The combined system integrates STAX’s mobile emissions control unit—which removes 99% of PM and 95% of NOx—with Seabound’s compact, cost-effective carbon capture technology. Connecting directly to a vessel’s exhaust pipe, STAX technology first removes criteria pollutants, turning the exhaust into purified gas. The gas is then directed through Seabound’s capture unit, isolating and storing up to 95% of carbon and 90% of sulfur before releasing the cleaned exhaust.
Since its launch in early 2024, STAX has established itself as the only emissions solution servicing all major vessel classes in California. To date, STAX has provided a critical pathway to CARB compliance in five major ports, captured more than 126 tons of pollutants, and will deploy its eighth barge this month. STAX recently announced $70 million in funding to fuel fleetwide carbon capture integration and international expansion this year.
Founded in late 2021, Seabound has established itself as a leading onboard carbon capture technology developer with its simple, modular, and cost-effective technology. Seabound recently completed a world- first demonstration of their onboard carbon capture system together with Lomar Shipping and Hapag Lloyd, successfully capturing CO2 at ~80% efficiency onboard a 3200 TEU container vessel. Seabound will be launching its first full-scale commercial carbon capture systems this year.
