Minnesota's Department of Commerce recommends closing Minnesota Power’s five oldest coal-fired power plants by 2020 to save consumers money. The Duluth News Tribune reports environmental groups have also sent letters urging the Public Utilities Commission to close the plants to reduce emissions.

The Public Utilities Commission ordered Xcel Energy to study the cost of new pollution control equipment at two of its coal-burning units in Sherburne County and compare that with the cost of replacing them with a cleaner alternative. Environmental groups consider the order a victory, but Xcel says it was planning something similar. The study is due next summer.

Clean-energy supporters are demanding that the Minnesota Public Utilities Commission order Xcel Energy to better plan how it will retire the two oldest and dirtiest coal-fired power plants at its Sherco Generating Station, which produces electricity for the Upper Midwest, the Pioneer Press reports. Renewable advocates packed an all-day hearing Thursday at the commission. They say Xcel has failed to study how wind- and solar-generated energy might replace the Sherco units.

Minnesota Power says it wants to further study the environmental benefits and economic impacts. The Department of Commerce recommends closing at least three of utility's coal-burning plants by 2016. Each unit is more than 50 years old. Environmental groups have also urged closing the coal power plants, while industrial users want state regulators to disregard the advice.

Xcel Energy will soon need to purchase new pollution control equipment if the company wants to keep burning coal at its largest Minnesota power plant in Becker. Environmental groups want the state to order the utility to study alternatives to coal, especially solar and wind power.

Gov. Dalrymple says if Minnesota energy regulators require utilities to pay more to burn coal it will hamper North Dakota's growing lignite industry, which already provides a large share of Minnesota's electric power. Regulators here imposed higher costs on coal-burners as part of a plan to require utilities to generate a quarter of their energy from renewable sources by 2024.

Spiritwood Station, 85 miles west of Fargo, cost $437 million to build, but now Minnesota's Great River Energy is shutting it down just after starting it up. One executive tells the Star Tribune that running it would mean losing money half the time. The utility plans to keep the plant offline until at least 2013.

Therefore, North Dakota officials feel the state should be exempt from a Minnesota law that requires utilities to pay more to burn coal, even those from out-of-state. It's part of Minnesota's Next Generation Energy Act of 2007 that requires new coal power emissions to be offset.