The vast majority of unconventional liquids today come from natural gas plant liquids (1.82 mbpd), refinery gains (0.97 mbpd), tar sands (1.3 mbpd), and biofuels (0.75 mbpd). CTL and GTL production is so low that EIA doesn’t see them reaching 0.01 mbpd until 2012. EIA projects that biofuels, CTL, and shale production will reach 1.2 mbpd by 2035. (Source: EIA, 2009 data.)
In the EIA’s Annual Energy Outlook 2010 Reference Case, production from unconventional liquids including tar sands, coal-to-liquids (CTL), gas-to-liquids (GTL), biofuels, extra heavy oil, and oil shale rises from an aggregate 4 mbpd in 2008 to 15 mbpd by 2035.
In our estimation, these are very optimistic estimates. However, even if they are correct, they will be unable to overcome oil depletion, which removes 3-4 mbpd from world supply every year.