GHG Emissions from CO2 Ship Transportation Chain

In a CCS chain, the CO2 is first captured and then transported to a suitable permanent storage site. The transport element could either be by pipeline, ship, or a combination of both, and the choice of transportation strategy will depend on several factors. Such as location of emission source, location of suitable storage sites and the volume of CO2 to be transported. In the ongoing Norwegian Longship project, the transport concept under planning is shipping of CO2 from one or two emission sites to an import hub located at Kollsnes, Norway. From Kollsnes, the CO2 is to be transported to an offshore aquifer through a pipeline. The scope of the ongoing project ''CO2LOS II'' (CO2 Logistics by Ship Phase II) is to reduce the cost of CO2 ship transportation by utilizing new technology and investigate optimization possibilities in the logistic chain. The project focuses on all activities between capture and permanent storage. Within this setting, this article encompasses a qualitative/quantitative assessment of greenhouse gas (GHG) emissions from the transport chain. This associated GHG emission is expected to be significantly lower than the quantities of CO2 stored, still it is worthwhile to estimate. The investigation has shown that it is the electricity consumption of the CO2 liquefaction plant that is the major contributor of GHG emissions from the transport chain followed by the fuel consumption of the ship, while the CO2 boil-off from intermediate storage tanks and the ship's cargo tanks is not a major contributor to the emissions in the transport chain. Therefore, the effort should be to reduce the fuel or power consumption or to change the fuel type to a lower carbon intensive fuel or power mix.