Energy is one of the foundations of industrial society. The transition to an ecologically sustainable energy system, based on renewable energy and energy efficiency, is essential for environmental reasons and has the potential for improving social equity. The easiest and least expensive scenarios for the transition involve electrifying most heating and transportation while substituting fossil fuelled electricity with renewable electricity (RElec), the bulk of which is supplied by variable renewable electricity (VRElec), mostly wind and solar photovoltaics (PV). Bulk electricity from wind and solar PV, ‘firmed up’ with storage, is now generally less expensive than new coal-fired power stations and is much cheaper than nuclear. Read More …