Most of the energy we use is wasted. Smarter technologies and designs that use energy more efficiently could provide the same or better services with far less energy, money, and risk. Moreover, the fossil fuels that provide most of our energy now generally cost more than the modern renewable sources that have already taken over two-thirds of the world’s power-plant market. These profound shifts in both demand and supply set the stage for rapid change in almost everything we thought we knew about energy. Oil suppliers have more unsellable than unburnable oil: they are more at risk from competition than from regulation. Electricity suppliers too face a swarm of disruptors that will transform their business beyond recognition. And meanwhile, Edison’s electric industry is merging with Ford’s auto industry to eat Rockefeller’s oil industry—while insurgents challenge incumbents in all three of these giant industries. These transformations offer remarkable opportunities for informed citizens in every community to build a durable economy and to make energy supplies resilient, so catastrophic interruptions of supply shift from inevitable to impossible. Evidence is now emerging in such major economies as China, India, USA, and EU that if based on the lowest-cost available resources, global climate protection can be not costly but profitable.