Oh, there's no way we can survive without a Department of Energy. It's not like we didn't have one for the country's first 200 years and then hastily slapped one together in the wake of some silly Arab oil embargo.
It would be nice to continue to develop a fusion reactor, manage nuclear waste disposal, track weapons grade nuclear material, develop industrial uses for quantum mechanics. But you are right, we can abandon these things and go back to being yeoman farmers.
I thought we were discussing the regulation of energy sources that actually exist. *shrug*
If you like, you can pretend you are dictator and regulate your energy fantasies in fantasy land.