US-UK Startups Debut ‘First’ Emissions and Carbon Capture System

STAX Engineering, a California-based company specializing in maritime emissions capture and control, and Seabound, a UK-headquartered onboard carbon capture firm, have demonstrated a ‘first-of-its-kind’ fully integrated emissions and carbon capture solution.

The end-to-end modular solution has now cleared the final trial, readying to explore an upcoming deployment with the Associated British Ports (ABP).

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During an event held in the Port of Long Beach last week, 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.

As explained, this breakthrough marks a significant milestone in port emissions reduction at a time when regulations are addressing the billions of tons of annual carbon emissions from the industry.

"Today (April 16) 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 Mike Walker, CEO of STAX.

"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."

"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."

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.

"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," said Paul J. G. Rennie, OBE.

Specifically, the combined system integrates STAX’s mobile emissions control unit—which removes 99% of PM and 95% of NOx—with Seabound’s 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 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 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 3,200 TEU container vessel. Seabound prepares to launch its first full-scale commercial carbon capture systems this year.