What if those old carrots you never got around to eating could be a renewable energy source, rather than something messy you had to clean out of your refrigerator bin? That’s the basic idea — though on a much smaller scale — behind Carvey Maigue’s new AuREUS system. Maigue, a 27-year-old engineering student at Mapúa University in the Philippines, just won the James Dyson Award sustainability prize for his invention.