A recent report by the International Energy Agency (IEA) outlines approaches to two scenarios for cutting global carbon dioxide levels by 2050. In the ACT scenario, which was introduced in 2006 and has now been revised, the levels of carbon dioxide would be reduced to 2005 levels by 2050 through a change in current energy technology. ACT would require “research, development, demonstration and deployment” (RDD&D) investments of $4.5-$5.5 trillion, with a total cost of $17 trillion. The newly introduced BLUE Map scenario would cut carbon dioxide levels 50% by 2050 and would require $45 trillion in funding until 2050, including $13-$16 trillion for RDD&D. Deployment would cost $2.4 trillion from 2008 to 2013. Under the BLUE Map scenario, 36% of energy savings would be derived from end-use efficiency, 21% would come from renewable energy and 19% would be from carbon-dioxide capture and storage technology. Biomass would account for 23% of primary energy.

Source: IEA