Six hours' power for one trip to the bathroom: African teenage girls create 'pee-powered' generator | Mail Online

Six hours' power for one trip to the bathroom: African teenage girls create 'pee-powered' generator

One litre of urine produces six hours of electricity.  But you need gas cylinders, borax and all sorts of kit.

Anything that flows can produce a current (nice pun that on)  by letting to flow drive a paddle wheel which in turn, drives a generator.
So why not collect a 45 gallon drum of village urine then let it flow down through a pipe to turn a paddle and then be collected into another barrels.
Top up the top barrel from the bottom one, plus extra input needed to make up for dribbles in the system and you got a continuous cycle of in one end and out the other, worked by gravity!