Technical, economic, and environmental assessment of CO₂ ship transport in carbon capture and storage

CO₂ shipping is integral to expediting the implementation Capture Utilization and Storage (CCUS) initiatives within the United Kingdom. This study introduces a framework, encompassing techno-economic and environmental aspects, evaluating the maritime transportation of approximately 5.9 million tons of CO₂ annually from the Solent region, equivalent to removing around 1.3 million cars from the roads. The assessment covers carbon capture, liquefaction, maritime transport, energy utilization, and storage processes. The results highlight the significance of achieving economies of scale to enhance the cost-effectiveness of CCUS by maritime transport. Comparing vessels of two sizes, medium pressure and low pressure, the low-pressure vessel demonstrates superior cost-effectiveness and operational efficiency per unit of cargo. The Life Cycle Cost (LCC) analysis indicates that liquefaction (∼£20) and transportation (∼£19) account for around 73% of total costs. Strategies such as incorporating incentives in port dues could reduce transportation costs to around £13 per ton. Additionally, offering incentives for using renewable energy electricity can mitigate costs and environmental impact in the liquefaction process. Carbon capture technology and port-related expenses contributed around £13 and £1, respectively. The emission trading scheme significantly reduces LCC (by 69%) among all scenarios, emphasizing the need to increase carbon pricing beyond around £84 for low-pressure vessels and £118 for medium-pressure vessels to enhance competitiveness. However, the sensitivity analysis in each scenario reveals that electricity prices and the discount rate are key drivers influencing both the LCC and NPC of CO₂ transport projects.