This is an idea I had a while ago, but clearly did nothing about, so it’s great to see someone else working on it.
Why not harness the kinetic motion of workout machines to power the gym? You already have hundreds of human hamsters bounding up stair machines, do you really need a coal plant miles away to power the TVs?
A gym in Hong Kong is on it, and while the technology is still pretty primitive (essentially a car battery) and costly ($15,000 investment to save $183 on the power bill), it’s an exciting thing to keep your eye on.
Those machines already contained small motion-powered generators used to light up their display screens. But the generators were producing significantly more electricity than was needed to power the screen, and the excess energy was being thrown off as heat.
The article also mentions generators embedded in shoes (so soldiers can stop carrying heavy batteries) and in the entrances to busy subway tunnels.