The potential role of energy efficiency in the transition to a low carbon society : a critical scenario review

International consensus is growing that a transition towards a low carbon society (LCS) is needed over the next 40 years. The G8, the Major Economies Forum on Energy and Climate, as well as the Ad Hoc Working Group on Long-term Cooperative Action under the United Nations Framework Convention on Climate Change, have concluded that states should prepare their own Low-emission Plans or Low-emission Development Plans and such plans are in development in an increasing number of countries. An analysis of recent long-term low emission scenarios for Germany shows that all scenarios rely heavily on a massive scale up of energy efficiency improvements based on past trends. However, in spite of the high potential that scenario developers assign to this strategy, huge uncertainty still exists in respect of where the efficiency potentials really lie, how and if they can be achieved and how much their successful implementation depends on more fundamental changes towards a more sustainable society (e.g. behavioural changes). In order to come to a better understanding of this issue we specifically examine the potential for energy efficiency in relation to particular demand sectors. Our comparative analysis shows that despite general agreement about the high importance of energy efficiency (EE), the perception on where and how to achieve it differ between the analysed scenarios. It also shows that the close nexus between energy efficiency and non-technical behavioural aspects is still little understood. This leads us to the conclusion that in order to support energy policy decisions more research should be done on energy efficiency potential. A better understanding of its potential would help energy efficiency to fulfil its role in the transition towards a LCS