Xcel closes the first unit at its Sherco coal plant this month, a milestone in…

BECKER — For more than 45 years, Xcel Energy's Sherburne County coal plant has been a constant, supporting the growth of the Twin Cities metro area with enough power for roughly 1.5 million homes. But its time as the anchor of Xcel's system is drawing to an end. On New Year's Eve, Unit 2 at Sherburne County Generating Station — or Sherco, as its known — will shut down for good, making it the biggest coal-fired generator yet to close in Minnesota. It's a remarkable milestone in Xcel's race to a carbon-free power grid by 2040, especially since the plant's other two units aren't far behind: They are slated to retire in 2026 and 2030…