using energy at the rate the sun stores energy in the earth through the water cycle, plant matter, wind, and solar rays.
using more energy than that will deplete the earths resources.
carl is right, but not for everyone. electricity for me comes from rivers, which are powered by the sun through the water cycle.
what we really need is super efficient satelites that harness more of the suns energy than we can with what cross section we have here on earth. maybe the moon? the problem is getting that energy here to earth. maybe lasers? mirrors?