Many sectors of the renewable energy industry are seeing unprecedented growth in deployment of existing proven technologies (solar PV, offshore wind) or major increases in research and development activity (biomass, biofuels, CSP). But advances in electricity storage seem to be proceeding at a much slower pace, perhaps because there is a belief that the creation of supergrids, possibly based on HVDC, will get around the problems by elegantly facilitating the balance of demand and supply over the wide area.