Project CAPTURED, a multi-partner initiative coordinated by the Global Centre for Maritime Decarbonisation (GCMD), has secured two regulatory developments that advance the commercial viability of onboard carbon capture and storage (OCCS) in shipping.

The EU Emissions Trading System (EU ETS) has formally accepted that CO₂ captured onboard vessels can be deducted from a vessel's reported emissions, reducing the number of EU Allowances (EUAs) that must be surrendered. Separately, the International Maritime Organization (IMO) gave in-principle support at MEPC 84 to recognise carbon mineralisation as a form of permanent CO₂ storage — complementing geological sequestration, which the IMO already accepts.

Both outcomes stem from a pilot completed in June 2025, in which Project CAPTURED demonstrated an end-to-end value chain for onboard captured and liquefied CO₂ (LCO2). The pilot showed that CO₂ captured aboard a vessel could be offloaded ship-to-ship, transported overland, and permanently bound through carbon mineralisation — a process that converts captured CO₂ into stable materials for industrial use.

To qualify for the EU ETS deduction, the captured CO₂ must be chemically and permanently bound in eligible products. Project CAPTURED demonstrated that CO₂ captured onboard can meet this requirement through carbon mineralisation.

According to GCMD, the pilot maintained CO₂ purity above 99.95 vol% at all custody-transfer points. A life-cycle assessment carried out by GCMD found that the pilot achieved a 7.9% net greenhouse gas (GHG) reduction, based on a gross capture rate of 10.7% onboard. GCMD claims that an optimised value chain based on the same gross capture rate could deliver GHG savings of 17.8%.

The IMO's in-principle recognition of carbon mineralisation, according to GCMD, broadens the downstream options for CO₂ captured onboard vessels and supports the development of maritime carbon value chains. Beyond providing a permanent storage pathway, carbon mineralisation also creates the potential for captured CO₂ to serve as a feedstock for industrial applications, which GCMD says could extend emissions reductions beyond the shipping sector.

GCMD brought together 11 partners across the maritime and industrial sectors for the project, including SMDERI-QET, Evergreen Marine Corp, Zhoushan Dejin Shipping, and Greenore/Baorong.

Professor Lynn Loo, CEO of GCMD, stated: "Project CAPTURED has moved OCCS beyond technical demonstration. The acceptance of the EU ETS deduction gives captured CO₂ a compliance value. At the same time, IMO's in-principle support for carbon mineralisation will help clarify how captured CO₂ can be treated after it leaves the vessel. Together, these milestones turn a pilot into a verified reference case for maritime carbon logistics, one that links regulatory recognition, commercial value and emissions impact."

Dr Su Yi, General Manager of SMDERI-QET, commented: "Project CAPTURED has demonstrated that captured CO₂ can be transferred from ship to ship and converted into construction materials. We have now taken a further step by achieving carbon deductions under the EU ETS, which means we have further explored the possibilities of the maritime carbon value chain. The IMO's in-principle support for carbon mineralisation means that our pathway is repeatable, offering a feasible blueprint for future emissions reductions in the shipping industry."