Study finds OCCS could reduce up to 20% CO2 emissions on “Stena Impero”

A project assessing the technical feasibility of onboard carbon capture and storage (OCCS) in the shipping sector has concluded that the technology has the potential to help maritime transport significantly reduce its greenhouse gas emissions, according to a joint statement on Thursday (10 October). 

The engineering project analysed the design and cost implications of retrofitting a carbon capture system on the medium-range tanker Stena Impero. It found that the technology could reduce the vessel’s carbon dioxide (CO2) emissions by as much as 20% per year, with a fuel consumption penalty of just under 10%.

The project was carried out by the Oil and Gas Climate Initiative (OGCI), the Global Centre for Maritime Decarbonisation (GCMD) and Stena Bulk together with a consortium of maritime organisations.

The project, Realising Maritime Carbon Capture to Demonstrate the Ability to Lower Emissions, (REMARCCABLE) was supported by a consortium comprising American Bureau of Shipping, Alfa Laval, Deltamarin, Lloyd’s Register, Seatrium, and TNO. It aimed to assess the viability of deploying carbon capture systems on vessels with minimal impact on operational constraints.

The cost of building and installing the full system on the Stena Impero is estimated at USD13.6 million, with an abatement cost of avoided CO2 for the first-of-a-kind prototype evaluated at USD 769/tonne CO2. 

However, the consortium believes that further research and development will drive down costs, making OCCS increasingly viable for the shipping industry.

The study also looked at incorporating OCCS on newbuild vessels, with the findings that improvements to capture rate and fuel penalty may be achieved using more efficient engines, heat pumps, and alternative solvents.

Professor Lynn Loo, CEO of GCMD, said: “OCCS has gained traction in recent years as a feasible approach to meet the 2023 IMO revised GHG emissions reduction targets. However, its adoption faces numerous hurdles, including the need to balance the tension between maximising CO2 capture rates while maintaining commercially acceptable CapEx and OpEx. This study provides quantitative insights on managing the trade-offs between the actual cost of operating OCCS and its emissions reductions potential.

“For OCCS systems to be practical, the industry needs to manage captured CO2 effectively. To this end, GCMD has previously completed a study to define the operational envelope for offloading onboard captured CO2, contributing to the whole-of-system approach to emissions reduction via carbon capture.”

Photo credit: Global Centre for Maritime Decarbonisation
Published: 11 October, 2024