What if there were a way to retrofit our innards to install a charge port for electronic devices. (USB-C, probably, or whatever you'd need.) What kind of power do we run on, how much energy could we output to a phone? (See maths below.) What would that do, physically? Would one get exhausted after a few minutes? Or hours?
Google says you get 1 KwH for every 860,420.65 calories (small C).
It also says that if you charge your device for 2 hours every other day at 1.2A. That means you'll spend 365 hours charging your device in a year. At 6 watts, that's 2190 watt-hours, or 2.19 kilowatt-hours (kWh). Which means that's 1,884,321 cal, or 1,884 Cal food units. That's pretty close to all the energy the average adult uses over a day, but spread over a year. Doesn't seem so bad. But it also seems really, really low. I feel like I'm missing something.