IIRC you stick an anode and kathode into the urine, separated by a semi-permeable membrane. This takes power of course. I'm not entirely convinced yet. Saying

IIRC you stick an anode and kathode into the urine, separated by a semi-permeable membrane. This takes power of course. I'm not entirely convinced yet. Saying something gives you "6 hours of electricity" means nothing. My watch battery gives me years of electricity for example.