World abatement of energy-related CO2 emissions by 2020
Efficiency measures account for two-thirds of the 3.8 Gt of abatement in 2020, with renewables accounting for close to one-fifth.
World abatement of energy-related CO2 emission in the 450 Scenario.
Source: OECD/IEA 2009 (via Dinah A. Koehler)