Century Aluminum is selling its idled Hawesville smelter in Western Kentucky to a data center company after choosing Oklahoma as the site for a new smelter, the first built in the U.S. since 1980. (Century Aluminum photo)Kentucky’s utility regulator has approved an electricity service contract for a hyperscale data center wanting to set up shop at a former Hancock County aluminum smelter that shuttered years ago, a key step forward before the po…