E3G, the non-profit organisation operating to accelerate the global transition to sustainable development, has published an excellent briefing paper that takes a second look at the July Communication on energy efficiency published by the European Commission. That Communication proposed a target of a 30 % improvement in energy efficiency by 2030. As the report states, the “proposed 30% 2030 target while sounding ambitious is also highly ambiguous. Depending on how it is defined, it could mean final savings in the real economy as low as 12% (if rebased to what is actually happening in the economy now) or as high as 34% (if set against 1990 EU energy consumption). As such there is a urgent need to seek clarity on the terms of the target.” The briefing paper is in a question and answer format that should help you understand this ambiguity better. The paper is also supported by an excellent infographic.
Energy in Demand - Sustainable Energy - Rod Janssen 