International shipping is crucial for global freight transport, but is mainly based on fossil fuels, leading to significant greenhouse gas (GHG) emissions. Global GHG emissions must peak by 2025 and drop by at least 43% by 2030 to limit global warming within 1.5◦C. This calls for urgent action in all sectors as well as shipping. Scaling up alternative fuels may take too long, considering technical modifications onboard the vessels, as well as fuel production and infrastructure for distribution. Many alternative fuels are also inherently dependent on access to clean electricity, which is already in a shortage. Carbon capture from ships is another route to emission reduction that can be implemented faster and without increasing the demand for renewable electricity.
Tankers, dry bulk carriers, and container vessels contribute a majority of global shipping emissions and are therefore prime candidates for carbon capture and storage. Solvent-based post-combustion capture is mature and suitable for marine applications, though technical, economic, environmental, and practical challenges remain. This paper assesses the feasibility of carbon capture for ships; both newbuild and retrofit vessels. While the limitation of space on board is a key factor in determining the feasibility, the increase in energy consumption is also challenging. This study indicates that energy use will increase with 70-100% with some variation between existing ships and newbuild.