In the real world? [ As in ... not the Horizon where he's just imagining limitless, non-destructible power sources. ] We got fuel cells. Most of 'em are pretty good, and they'll keep working so long as they don't get damaged. They're like — uh ... batteries.

[ He can only hope that this guy at least understands what a battery is or the comparison isn't going to help explain anything. ]

I'm guessing magic would be pretty handy though. You got some of that? The magic?