I'd think that's already a thing.

I have a Peltier-powered fan that I put on top of my wood stove. It spins extremely fast. I like it because I can tell how hot my stove is by looking at the fan, instead of walking over to the wood stove and looking at the thermometer: https://www.amazon.com/s?k=wood+stove+fan&sprefix=wood+st%2C...

You can even find devices that you can put into a campfire to charge a phone: https://www.iphoneness.com/cool-finds/campfire-chargers-for-...