OljeBig Oil bets big on Permian growthWelcome to another Thursday Energy Source.ExxonMobil and Chevron are both putting the Permian, which spans west Texas and south-east New Mexico, at the centre of their output growth strategies and are signalling double-digit growth this year.Foto: Eli Hartman/AP/NTBDerek Brower (FT)Justin Jacobs (FT)Amanda Chu (FT)