[sbierwagen]

Around 2010 or so I worked for a skyscraper in downtown Seattle. There was a heat wave and the utility needed to shed load. The mechanism for doing that was someone calling our front desk and saying "Hello, please shut off your lights."

(Commercial lighting runs at 277v, so it's all on separate circuits from wall outlets. You can shut off the lights in a building without killing the servers, for example)

We had remote-controlled breakers, so doing that was a couple clicks of the mouse. But if nobody had picked up the phone, they would have needed cops to break into the electrical room on each floor and start flipping breakers by hand.