Two ethanol makers are complaining to the Minnesota Public Utilities Commission that poor decisions and wasteful spending made by Great River Energy have caused the utility to raise its rate 58 percent in seven years, the Star Tribune reports.

The PUC is currently reviewing a 15-year plan by Great River to supply future customer needs for power, but the commission has no authority to set electric rates for local co-ops unless its customers vote to be regulated.

Great River Energy, Minnesota's second-largest power company based in Maple Grove, is a nonprofit wholesale power supplier to 28 Minnesota cooperative electric utilities.

“The companies are simply no longer able to sit on the sidelines in light of the massive spike in their rates over the last few years,” Minneapolis attorney David Aafedt, who represents ethanol makers Al-Corn Clean Fuel of Claremont, Minn., and Green Plains Renewable Energy, an Omaha-based company with a plant in Fergus Falls, Minn., told the newspaper.

“We project no need for new generation for at least the next decade,” added Jon Brekke, Great River Energy’s vice president of member services. “We are in a good position for shaping our future in a competitive way.”

Great River expects its wholesale rates to increase 1 percent annually over the next five years, according to the Star Tribune.