Can subsea shuttles be a cost-competitive solution for CO2 transport?

Considering the role that offshore ${\text{CO}}_2$ storage is expected to play in deploying carbon capture and storage, enabling cost-efficient and flexible solutions for transporting ${\text{CO}}_2$ to relevant storage locations will be crucial. While pipeline and ship-based approaches have long been considered the most relevant options, transport via subsea shuttles is a new concept that has also been proposed in the past couple of years. The present study seeks to understand if this new approach could be cost-efficient compared to current and upcoming ship-based transport concepts.

The result shows that the shuttle concept could be cost-competitive with currently mature 15 barg-based shipping, especially if the subsea shuttle connects to a ${\text{CO}}_2$ pipeline infrastructure rather than to the reservoir directly, although cost-competitiveness is achieved only for a limited range of volumes and distances. However, it is unlikely that this concept would be cost-attractive compared to the upcoming 7 barg-based shipping, and sensitivity analyses highlight that the subsea shuttle investment cost would need to fall to unlikely low levels to reverse this trend. Thus, this study concludes that the subsea shuttle concept is unlikely to become a significant solution for transporting ${\text{CO}}_2$ to offshore storage.