Atop all "revolving door" entryways, we should install a device that captures the energy generated each day. Thinking about downtown Chicago alone, the daily motion/energy created would be of some small significance, I have to imagine.

While I doubt this would generate enough power to, say, light an entire skyscraper... it might be enough to operate, say, the Exit lights on the ground floor. Something small.

It seems like we generate a decent amount of energy each day pushing these revolving doors - why not try to capture some of it back, and offset our energy use? Sort of like the energy-generating dance floor:

I doubt I'm the first to come up with this idea. It just struck me the other day, walking in and out of one of those revolving doors.