This seems like a total "dad product." But I guess looking like a dork is better than dying of heat stroke . . .
Clothes with built-in FANS are getting more and more popular. Especially in Japan where they've been a thing for a while now. (Here's a photo.)
A former Sony engineer came up with the idea, and started selling "fan jackets" in 2004. The name of his company literally translates as "air-conditioned clothes."
If you're having trouble picturing it, just think of those inflatable dinosaur costumes people wear for Halloween. They puff up just like that and work the same way.
Early versions weren't breathable enough, and the batteries didn't last long. But now they can go all day. The power-tool company Mikita started selling their own version for construction workers in 2015. They say sales have been way up the last few years.
There are also a million knock-offs on Amazon now that cost anywhere from $40 to $300. So if you don't care about being made fun of by literally EVERYONE, it's another way to beat the heat.