GCMD launches Onboard Carbon Capture and Storage Impact Calculator

The Global Centre for Maritime Decarbonisation (GCMD) on Monday (19 October) announced the launching of its Onboard Carbon Capture and Storage (OCCS) Impact Calculator during its fifth anniversary celebrations. 

Drawing on learnings from Project CAPTURED, it helps users explore measurement and tracking considerations along the carbon value chain, from onboard capture and storage through offloading and transport to downstream mineralisation.

On why this matters, GCMD said regulatory recognition of onboard captured CO2 may give it compliance value under the EU ETS.

For shipowners, this recognition raises a direct commercial question: how much CO2 can be captured, stored, offloaded and mineralised, and how might these quantities translate into a reduction in the number of EU Allowances (EUAs) they need to surrender?

“The calculator provides a concrete way to explore this relationship,” it said. 

Users can explore how:

• Capture rate, onboard storage capacity and OCCS operating duration affect the amount of CO2 captured
• Losses of captured CO2 during offloading and downstream processing affect the quantity ultimately mineralised
• These factors influence the potential reduction in EU Allowances surrender for the shipowner under the EU ETS

Note: The calculator can be found here. 

Related: GCMD: Project CAPTURED achieves two regulatory milestones for onboard captured CO2
Related: GCMD, Equinor to combine expertise on alternative bunker fuels, decarbonisation solutions

Photo credit: Global Centre for Maritime Decarbonisation
Published: 20 October, 2026