7.1 A brief introduction to CO2 transportation
Safely and reliably transporting CO2 from where it is captured to a storage site is an important stage in the CCS process. Transportation of CO2 is already a reality, occurring daily in many parts of the world.
Pipelines are – and are likely to continue to be – the most common method of transporting the very large quantities of CO2 involved in CCS. There are already millions of kilometres of pipelines around the world that transport various gases, including CO2.
Transport of smaller volumes of CO2 is currently undertaken by truck and rail for industrial and food grade CO2The cost of transportation by truck or train is relatively high per tonne of CO2. For the large volume of CO2 that would be captured via CCS, it is much cheaper to transport by pipeline, so it is unlikely that truck and rail transport will have a significant role in CCS except for small pilot projects.
Ship transportation can be an alternative option for many regions of the world. Shipment of CO2 already takes place on a small scale in Europe, where ships transport food-quality CO2 (around 1000 tonnes) from large point sources to coastal distribution terminals. Larger-scale shipment of CO2, with capacities in the range of 10,000 to 40,000 m3, is likely to have much in common with the shipment of liquefied petroleum gas (LPG), an area in which there is already a great deal of expertise and which has developed into a worldwide industry over a period of 70 years.
As discussed in the cost section of this report, when looking at all the components of an integrated CCS project, the transportation aspect of the project contributes only a small proportion of the total cost compared to capture, compression, and storage. Even though the cost share of CO2 transportation may be in the order of 2–5 per cent of the total CCS facility, they are still significant in the demonstration phase with US$2–7 per tonne of CO2 for transportation distances under 200 km. Studies undertaken by Element. Energy (2010a) and ZEP (2011) also suggest that, over time, when CCS hubs or clusters have emerged (as opposed to point-to-point projects), a significant reduction in total transportation distance and costs may be achieved.
The existing experience with CO2 transportation may have led to a general perception among the CCS community that CO2 transport is not considered a major barrier to the deployment of CCS. While in general this may be true, this component of the CCS chain requires careful consideration in design and operation. Before discussing these, this chapter will first outline the status and new developments of CO2 transportation infrastructure, including the emerging CCS hubs, clusters, and networks.