EOR, or enhanced oil recovery, is an obvious good and for the most part the CO2 used therein is tapped from natural underground resources, so it involves no energy loss at generation plants and no loss of CO2 to the biosphere. Generating plant CCS though is a horse of an entirely different color.
The United States can extract billions of barrels of otherwise unrecoverable oil by injecting carbon dioxide (CO2) underground and also needs to bury CO2, produced by its reliance on coal for power and industry, to fight climate change.
Until now, the CO2 used for recovering oil has been specially extracted from underground but the government is working to use the lure of oil extraction to encourage the capture and storage of carbon produced from power stations.
Pumping carbon dioxide into depleted fields to recover oil left behind by conventional production methods and waterflooding accounts for more than 300,000 barrels per day (bpd) of U.S. oil output, according to a survey published earlier this year in the Oil and Gas Journal, up from 200,000 bpd in 2004 and less than 100,000 bpd in 1990.
The first commercial-scale carbon dioxide injections to support enhanced oil recovery (EOR) began at Scurry County, Texas in 1972. Since then, the United States has become the largest employer of CO2-EOR technology in the world.
In 2012, CO2 injection was being used to support EOR at more than 100 projects across the United States, up from around 50 in 1990 (“Miscible CO2 now eclipses steam in U.S. EOR production” Oil and Gas Journal, April 2, 2012).
Ironically, given that policymakers are worried about global warming as a result of man-made emissions, almost all the CO2 being used in EOR projects comes from natural sources.
CO2 is produced from underground formations where it occurs naturally, transported by pipeline, then pumped back into depleted oil fields to support oil extraction. There is no net benefit in terms of reduced atmospheric CO2.