Global energy efficiency improvement in the long term: a demand- and supply-side perspective

This study assessed technical potentials for energy efficiency improvement in 2050 in a global context. The reference scenario is based on the World Energy Outlook of the International Energy Agency 2007 edition and assumptions regarding gross domestic product developments after 2030. In the reference scenario, worldwide final energy demand almost doubles from 293 EJ in 2005 to 571 EJ in 2050 and primary energy supply increases from 439 EJ in 2005 to 867 EJ in 2050 (excluding non-energy use). It is estimated that, by exploiting the technical potential for energy efficiency improvement in energy demand sectors, this growth can be limited to 8% or 317 EJ final energy demand and 473 EJ primary energy supply in 2050. This corresponds to a potential for demand-side energy efficiency improvement of 44% in 2050, in comparison to reference energy use. In addition, a potential exists for improving energy efficiency in the transformation sector. In 2005, as much as 33% of primary energy supply is lost in the transformation and distribution of primary energy. It is estimated that this share can be reduced to 19% in 2050 by, e. g. improving energy efficiency of fossil-fired power generation (assuming no changes in the fuel mix for power generation). Including the potential for energy efficiency improvement in energy demand sectors, total primary energy supply would then decrease by 10% from 439 EJ in 2005 to 393 EJ in 2050. This contributes to a total potential for energy efficiency improvement of 55% in 2050 in comparison to reference primary energy supply.