CO 2 injection EOR is most appropriate for light, condensate and volatile oil reservoirs, and for carbonate formations that exhibit low porosity. Injected CO 2 and oil are miscible, meaning that they mix in all proportions. Oil becomes less viscous upon mixing with CO 2 and flows more easily to the wellbore.

 

Whether a combination of carbon capture and EOR is economic depends on the costs of capturing anthropogenic CO 2, compressing and transporting it, as well as those of EOR. These costs are offset by revenue from the incremental oil production and, potentially, the cost of carbon (i.e., a credit if a carbon tax or emissions trading program is in place). The figure below shows that if the prices of oil and carbon are sufficiently high (as in August, 2009), costs of carbon capture and EOR are offset; on the other hand, lower oil and carbon prices (oil price, $40/barrel; carbon price, $15/tonne; February of 2009) result in the process being uneconomic.