This paper draws on evidence from the last two centuries of industrialisation, analysing the evolution of energy intensity over the long- and short-run. We argue that the increased specialisation of the fuel mix, coupled with accelerating convergence of both the sectoral and technological composition of economies, will continue to improve energy intensity of economic output and to reduce the reliance on any single energy resource. This analysis suggests that even high growth in per capita income over the next 20 years need not be constrained by resource availability. (C) 2012 Elsevier Ltd. All rights reserved.