AdvertisementCoal May Pass Oil As World's No. 1 Energy Source By 2017, Study SaysDecember 18, 2012Bill ChappellfacebookEmailChina and India are projected to propel coal's challenge of oil as the world's top energy source within the next five years, according to a new study. Here, a man rides a bicycle toward a coal-fired power station in China's Guangdong province last year. (AFP/Getty Images)