Four girls at a Nigerian school have developed an electricity generator powered by urine in response to the country's energy problems.  The girls, students at the Doregos Private Academy School in Lagos, said they developed the urine-powered generator due to the difficulty in finding fuel to power the generators many people in the country rely on due to the country's frequent outages.  The girls said the generator is powered by the hydrogen and oxygen released by the urine.  Adebola Duro-Aina, another student on the team, said about 1 1/2 gallons of urine can power the generator for about 36 hours.