I may be getting this wrong so be sure to read for yourself.

It seems that in order to extract the last little bit of oil, they will now store CO2 (from industrial sites) in holding tanks under the ground and then pump it into the earth which will force more oil up, out of the ground.

Ol companies like the idea and think it will work but they don't want to pay for it. If this new technology is to be developed, the taxpayers are expected to foot the bill. (Heard this on the local news last night).

" Oil production is slowing as many of the North Sea wells mature, and carbon dioxide pumped down the hole can loosen up and release the remaining oil."

http://www.technologyreview.com/Biztech/17892/