Project demonstrates potential of onboard carbon capture

The study, part of the “Realising Maritime Carbon Capture to Demonstrate the Ability to Lower Emissions” (REMARCCABLE) project, was carried out by the Oil and Gas Climate Initiative (OGCI), the Global Centre for Maritime Decarbonisation (GCMD), and Stena Bulk, in partnership with a consortium of leading maritime organisations.

The project focused on retrofitting a carbon capture system onto the medium-range tanker Stena Impero and demonstrated that OCCS could reduce carbon dioxide (CO2) emissions by up to 20% annually, with a manageable fuel consumption penalty of just under 10%. The cost of the system was estimated at $13.6 million, with an initial abatement cost of $769 per ton of CO2. However, the consortium is optimistic that ongoing research and development will help reduce these costs, making OCCS a more economically viable solution for the shipping industry.

The consortium backing REMARCCABLE includes the American Bureau of Shipping, Alfa Laval, Deltamarin, Lloyd’s Register, Seatrium, and TNO. Together, these organisations assessed the design and cost implications of OCCS retrofits, as well as the potential for integrating such systems into newbuild vessels. The study found that using more efficient engines, heat pumps, and alternative solvents could improve capture rates and reduce fuel penalties in future applications.

Dr. Michael Traver, head of OGCI’s Transport Workstream, highlighted the importance of the findings: “This study is a major milestone in understanding the potential of using carbon capture technology to decarbonise the shipping industry. The technical feasibility demonstrated in the project is highly encouraging.”

Professor Lynn Loo, CEO of GCMD, echoed this sentiment, acknowledging the growing traction of OCCS as a viable pathway to meet the International Maritime Organization’s (IMO) revised greenhouse gas (GHG) emissions targets. Loo noted that balancing CO2 capture rates with commercially acceptable capital and operational expenditures remains a challenge, but that this study offers valuable insights into how these trade-offs can be managed.

Stena Bulk’s president and CEO, Erik Hånell, also emphasised the long-term potential of OCCS for the maritime industry: “While initial costs for first movers may be high, further research and development will drive down expenses, making OCCS an increasingly practical solution. The results of this project will be instrumental in evaluating both the operational and commercial viability of capturing CO2 at sea.”

The study also highlighted several challenges that need to be addressed for OCCS to become widely adopted. On the regulatory front, the industry awaits guidance from the IMO’s Correspondence Group, which is working on a framework for OCCS to be discussed at the Marine Environment Protection Committee (MEPC) 83. Operational challenges include recurring costs from fuel penalties, solvent replenishment, manpower, and maintenance, as well as the logistics of offloading captured CO2, which is still in its early stages.

For OCCS to be truly practical, ports will need to develop infrastructure for offloading and storing captured CO2, and clear policies will be required for managing the final sequestration or utilisation of the captured carbon. Collaboration across the maritime value chain will be essential to address these hurdles.

The full REMARCCABLE project report, available through OGCI and GCMD, provides detailed technical specifications, cost analyses, and recommendations for further developing OCCS technology, positioning it as a promising solution in the maritime industry’s decarbonisation journey