Meeting this challenge will require harnessing all available energy resources and technologies, according to local circumstances, coupled with energy efficiency measures, especially to upgrade grids and reduce transmission losses. As well as reflecting local endowments and resource potential, the energy mix should evolve in such a way as to kick-start the structural transformation process, while maximizing the development opportunities within the energy value chain. While fossil-fuel-based generation is likely to play a continuing role where substantial sunk costs have already been incurred and in countries with significant reserves, a progressive move towards renewable technologies could offer substantial development opportunities as well as environmental co-benefits.