Atoms are recyclable, and energy is conserved - yet there is a petty matter of fighting entropy. Without energy flows you can't put atoms in desired order, run internet and modern agriculture, support metabolism of the global economy.

And no, I do not think that renewables would save the planet activity as it is now. Some downsizing is bound to happen, as extraction of oil and aluminum will require more investments of the same energy. The only thing that might keep the bonanza going is a determined jump towards a type II civilization, perhaps.