It might sound a little like science fiction, but this is actually true.
The outdoor waterparks on the waterparkthere, for instance, are built on an internal combustion engine that uses propane.
When you’re outside, the engine cools down.
But when you’re inside, the propane tanks are used to heat water to the point that it starts to flow, which makes the indoor water park feel like an indoor amusement park.
In this video from Engadgets, we find out exactly how to make an indoor indoor waterpark feel like a waterpark.