Petrole and radioactivity are the cleanest and cheapest energies we know
Hemp fuel is much cleaner, it has a negative carbon footprint, so the more we use, the more oxygen earth will have.
Good point, when you live completely in the dark and solar power is unavailable you're going to need a power source for your electric guitar and facilities for a multimillion person outdoor rave.
http://fuelcellstore.com/direct-ethanol-fuel-cell-kit-fcjj-22That or the cheapest diesel generators you can find on craigslist and I'll bet reports will come in that plumes of black exhaust fumes smelling like doughnuts or popcorn or what ever "bio-fuel" they can get cheapest.
Woodstock will look like 10 hippies around a camp fire.