Technical and economic feasibility analysis of a subsea shuttle tanker for CO2 transport to the troll field

Abstract The Subsea Shuttle Tanker (SST) was presented by the authors as an innovative and cost-effective solution in several research works. This new approach offers a viable alternative to subsea pipelines and shuttle tanker ships for transporting liquid CO 2 from onshore facilities to marginal offshore reservoirs. A previous technical–economic feasibility study found that the SST is generally economically competitive to the subsea pipelines and shuttle tanker ships for distances below 180 km and CO 2 transport volumes of one million tons per annum (mtpa). The economic cost models are based on those developed in Maritime UN-manned Navigation through Intelligence in Network (MUNIN) D 9.3 and the Zero Emission Platform (ZEP) projects. This paper will take this previous study further by focusing on performing the technical and economic feasibility analysis for operation in the Troll field on the Norwegian continental shelf (NCS), which has a transport distance of 65 km and a CO 2 volume of 1.5 mtpa. Two SST design solutions are investigated by downscaling and upscaling the reference baseline design to evaluate SST’s technical feasibility. Using the abovementioned cost models, the CO 2 transportation cost per ton using SST is compared with subsea pipelines and tanker ships. The numerical results show that it is economically feasible to manufacture SST with cargo capacities of 4453 m 3 and 2203 m 3 . Furthermore, the results show that the SST is the most cost-effective option for transporting low-volume CO 2 (1.5 mtpa) over short distances.