I'm writing a sci-fi novel and am having a hard time coming up with a new energy source that DOESN'T revolve around the widely popular "nuclear" option everyone favors so much. I've tried researching other energy types that scientists are investigating but everyone just assumes solar, wind, or nuclear are the future and none of those are interesting nor special in a science fiction novel. My writing style can't fathom just random facts or conjure up nonsense out of thin air. I'm trying to make my project as close to scientifically possible and accurate as I can, but this might be the thing that makes or breaks that idea. I've so far been given advice from friends and D&D DM's that I should do research into Lunar power and Dark Matter. The problems with these are that Lunar is just another form of Solar energy and Dark Matter is so impossible to study that its properties are yet to be explored or tested in a controlled environment. So my question is simple: What would you try exploring as an alternate energy source for the future that doesn't follow the stereotype of nukes, the sun, and wind turbines?