Great River Energy said it aims to produce 50 percent of its electricity from renewable resources by 2030, up from 25 percent currently.

Maple Grove-based Great River, one of the nation's largest wholesale power cooperatives, said Wednesday it plans to climb to 30 percent renewable power production by 2020 and 40 percent by 2025.

"We continue to evolve our power supply portfolio, delivering more renewable energy to our member-owned cooperatives to help them remain competitive in a changing market," Great River CEO David Saggau said in a statement.

Great River supplies electricity to 28 retail power cooperatives in Minnesota and parts of Wisconsin, which together serve about 695,000 consumers.

Great River has long been dependent on coal-fired power, but it's increasingly adding renewable generation sources, primarily wind. The company last year announced a new wind farm in North Dakota with a capacity of 300 megawatts, enough to power 120,000 homes when the wind is blowing.

That project, which is slated to come online by 2020, will bring Great River's total wind-power generation capacity to almost 750 megawatts. Great River plans to add 500 megawatts more of wind power from 2020 to 2030, said Jon Brekke, vice president and chief power supply officer at Great River.

The details of wind additions in the 2020s have yet to be worked out, but they will be critical for Great River to meet its 50 percent renewable goal. Hydropower supply contracts with Manitoba Hydro, a major electricity producer, will also play a role, Brekke said.

Great River's new renewable goals garnered praise from clean energy groups. "Less carbon, more electricity — that's the future for smart utilities," said Rolf Nordstrom, head of the Great Plains Institute, in a statement. Minneapolis-based Great Plains is a nonprofit energy research group.

Great River has no plans to close Coal Creek Station, its 1,145-megawatt, coal-fired plant in central North Dakota. Coal Creek, North Dakota's largest power plant, is next to a lignite coal mine. Such mine-mouth power operations are considerably cheaper to run than coal generators elsewhere.

Still, Great River has retooled Coal Creek in recent years so that its production can be reduced when wind power is surging. It will use less coal as it operates more variably.

"The megawatt hours we produce from our coal facilities will be less than it is now, but we expect them to be an important part of our portfolio and a hedge on our market costs going forward," Brekke said. Great River also operates a much smaller 99-megawatt coal-fired plant in eastern North Dakota.

The growth of wind power in the Upper Midwest — at many utilities — is increasingly dictating the dispatch of electricity on the grid. When the wind is blowing, it's the cheapest source of power.

"Wind is going to run first because it has free fuel costs," Brekke said.

Mike Hughlett • 612-673-7003