The Global Centre for Maritime Decarbonisation (GCMD) on Tuesday (6 January) has published a life cycle assessment (LCA) of the greenhouse gas (GHG) emissions from Project CAPTURED—the world’s first ship-to-ship offloading of onboard captured and liquefied CO₂ (LCO₂) with downstream utilisation, completed in June 2025.
Verified by DNV, the LCA quantifies GHG emissions and savings across the pilot’s entire carbon value chain, tracing CO₂ captured and liquefied on an ocean-going container vessel to ship-to-ship and ship-to-truck transfers, overland transport, and its utilisation at an industrial facility.
There, the CO2 was used as a feedstock to recycle steel slag into post-carbonated slag (PCS) and produce precipitated calcium carbonate (PCC) through carbon mineralisation, a process in which captured CO2 is chemically converted into stable carbonates, fixing carbon long term.
OCCS as a mid-term decarbonisation pathway – and why LCA matters Onboard carbon capture and storage (OCCS) is increasingly recognised as a promising mid-term pathway to reduce emissions from vessels that continue to rely on conventional fuels.
By capturing CO₂ from exhaust gases, OCCS can significantly reduce onboard fuel-combustion (tank-to-wake) emissions. However, its true contribution to decarbonisation must be evaluated across the entire carbon value chain, including its final utilisation and/ or permanent storage.
An LCA quantifies these full-chain GHG impacts transparently and systematically, evaluating that emissions savings achieved onboard are not offset by upstream or downstream burdens.
Project CAPTURED, with OCCS operating at a 10.7% capture rate, demonstrated 7.9% GHG emissions savings across the entire carbon value chain. This corresponds to 0.84 tonnes of CO2 savings realised per tonne of CO2 captured and offloaded from the vessel.
These savings were achieved despite several operational constraints, including the absence of a waste heat recovery system onboard that increased the fuel penalty, long-distance overland truck transport, as well as CO2 venting during offloading and handling.
When these inefficiencies are addressed, GHG emissions savings increase markedly to 17.8%, equivalent to approximately two tonnes of CO2 avoided per tonne of CO2 captured and offloaded from the vessel.
Professor Lynn Loo, CEO of GCMD, said, “Project CAPTURED shows that onboard carbon capture, when thoughtfully integrated with utilisation pathways, can deliver real emissions reductions today while we continue to scale up low- and zero-carbon fuels.
“It also highlights how we measure and account for those reductions matter. If our frameworks continue to ignore avoided emissions and displaced carbon, we risk disincentivising investments in solutions that can meaningfully bend the emissions curve.”
Photo credit: Global Centre for Maritime Decarbonisation
Published: 7 January, 2026
