Your purpose in life is now to supply power to the grid. At first it'll be great, you're celebrated as a neat way to keep the baseline juice coming as fossil fuels phase out. Then you're asked to stay back a few hours as there's a shortfall predicted, you oblige out of duty. Then one day you wake up in a drugged daze, strapped to a giant battery, your nutritional needs piped directly to your bloodstream as scientists ever so carefully cut you open to try and figure out how this works, because despite their best efforts to keep your wrecked body alive, one day you will die, and the utter reliance of the grid on your free energy will die with it, and with that kick off the downfall of humanity.

I’d pick charging batteries while holding them as well except only if it doesn’t affect the battery health of the battery. I’d never have to charge my phone again.