32-year-old green energy entrepreneur Yetunde Fadeyi will never forget what inspired her to start a clean energy company in Nigeria. As a six-year-old, Fadeyi’s best friend, Fatima, was killed by carbon monoxide poisoning in her Lagos home, along with her father and pregnant mother. “She often came over for sleepovers. But that day she didn’t,” says Fadeyi. “It was the time that they were stealing people’s generators, so they kept [the generator] in an enclosed area and by the time it was morning they were dead.” Petrol-powered generators like the one Fatima’s family had are valuable assets be…