Connexus Energy will terminate its membership in Great River Energy, allowing it to roll out more renewable energy projects.

Ramsey-based Connexus currently is the largest of 28 retail power co-ops that own and buy power from wholesale electricity supplier Great River. In January, Connexus will no longer be a member-owner, only a customer.

Maple Grove-based Great River's member co-ops voted on Tuesday in favor of the new arrangement. The boards of Connexus and Great River did the same earlier this summer.

The new Connexus contract goes into effect in January.

"We now have the flexibility to chart our own course and pick and choose our resources to support our growth," said Brian Burandt, Connexus' vice president for power supply and business development.

Connexus, Minnesota's largest retail electric co-op with 141,000 members, told Great River a year ago it wanted to end its membership, saying the relationship was inflexible and too costly. The two companies have been negotiating since then.

Connexus has been a member of Great River since the latter was created in 1999. While many co-ops still serve primarily rural communities, Connexus' territory includes fast-growing parts of Anoka, Chisago, Hennepin, Isanti, Ramsey, Sherburne and Washington counties.

Connexus' new contract as a Great River customer — like its contract as a member — extends until 2045. And Connexus will still be Great River's single largest power consumer, accounting for about 22% of its production.

But Connexus is no longer committed to getting 95% of its electricity from Great River. As a member-owner, it also was not allowed to produce more than 5% of its power on its own. Connexus has been adding solar arrays and battery storage, bumping against the 5% cap.

Connexus has been a leader among co-ops in using solar energy, and it has gone further than any of the state's investor-owned electric utilities in deploying battery storage. It currently has four solar sites with 20 megawatts of capacity, along with 30 megawatt hours of battery storage.

"We have had strong membership feedback saying, 'Please add more renewables, but don't raise our rates,' " Burandt said.

Connexus plans to add another 10 megawatts of solar capacity in the next couple of years, including four megawatts from a novel project at Anoka County's landfill.

The company said its efforts will be aided by recently passed federal legislation that extends tax subsidies to solar and other renewables.

Connexus said its new contract will provide cost savings to the co-op's members, though it declined to disclose any numbers.

Jon Brekke, Great River's chief power supply officer, called the agreement with Connexus "unique."

It will have minimal effect on Great River: Connexus' exit will push up rates on Great River's other customers by less than 1% over the next 23 years, he said.

Meanwhile, Connexus "is getting self-determination for the future," and Great River is getting a 23-year contract "with a large distribution cooperative we have a lot of history with," Brekke said.