There is enough energy in, on, and above the planet to provide for current needs, and for projected needs into the arbitrary future. Wind, solar, geothermal, and nuclear sources of energy can be -- and are! -- deployed more and more as energy scientists and energy engineers find ways to get to them and exploit them. There is no scarcity of energy on this planet, there is only a lack of access. So asserting that we need to use all this energy efficiently is misguided at best, and really doesn't help with the real issue, which is access.
Let me rephrase this, slightly. Protesting we need efficiency when there really is no scarcity is the same misguided idea behind using fiscal austerity measures to fix broken economies. Just like with energy, there is *plenty* of money out there. And just like with energy, the problem is figuring out how to get to all that wealth and redistribute it so that everybody can benefit from it.