U.S. electricity costs are poised to reach the highest level since 1999 because railroads are too clogged to deliver enough coal to power plants. While the U.S. has the world’s biggest coal reserves, utilities are forecast by the government to end the year with the lowest stockpiles since 2005. With carriers including BNSF Railway jammed with record shipments of oil and grains, Xcel Energy Inc. (XEL) and other power producers say they can’t get the coal they need. The rail delays mean utilities haven’t rebuilt inventories that fell to a seven-year low last winter. Power producers filed 10 notices this year warning regulators that stocks were low enough to threaten generation, compared with two filings in 2013. Utilities have been obliged to rely more on natural gas, increasing costs for consumers. “There’s plenty of coal,”Jim Thompson, a director of coal for IHS, an Englewood, Colorado-based energy and industrial analytics […]