Gates Foundation's Competition May Have Handle on Reinvented ToiletThese aren't your typical loos. One uses microwave energy to transform human waste into electricity. Another captures urine and uses it for flushing. And still another turns excrement into charcoal. They are part of a Bill & Melinda Gates Foundation competition to reinvent the toilet for the 2.6 billion people around the world who don't have access to modern sanitation.