Chicago Tribune: As the number of wind turbines scattered along the South Dakota skyline continues to grow, moving the energy they provide out of the state requires a fundamental change. Dusty Johnson of the state Public Utilities Commission puts it simply: A local power transmission system has to become national. Trying to transmit wind power to more populous states is not a new problem. But when federal regulators recently approved generous incentives for a proposed 3,000-mile, high-voltage …