The unexpected challenges of using energy intensity as a policy objective: Examining the debate over the APEC energy intensity goal

The three lessons are as follows: (1) Energy intensity improvement is happening surprisingly quickly, but not quickly enough to meet the world's energy challenges. (2) It is difficult to find a definition of energy intensity that can make it suitable for use as an indicator of regional energy efficiency. (3) Whether the GDP's of individual economies are converted to common currency using market exchange rates or purchasing power parity (PPP) can dramatically change regional energy intensity improvement calculations.