One large solar energy project is moving ahead in rural Minnesota, while another was delayed Thursday by concerns over the loss of prime farmland.

Great River Energy, the state's second largest power generator, said it plans to build a 13-acre solar array 6 miles east of Buffalo, Minn. It is the largest solar project yet for the wholesale power cooperative, which has built smaller solar farms at its Maple Grove headquarters and 19 other sites.

A far larger solar project, proposed by NextEra Energy Resources on 515 acres of farmland 3 miles east of Marshall, Minn., was delayed by state regulators who want to further study whether it complies with state rules to protect prime agricultural land.

"There have been a lot of questions asked," said Beverly Jones Heydinger, chairwoman of the Minnesota Public Utilities Commission, whose motion to study the farmland question passed 5-0.

At issue is whether NextEra could have found a "prudent and feasible" alternate site that isn't prime farmland for its 62-megawatt solar generator to be built for Xcel Energy — or whether a variance should be granted to the rule, which applies to large power generators. One megawatt is 1 million watts.

Four neighbors of the proposed Marshall solar project raised the farmland-protection concern. They oppose replacing cropland with an industrial-scale solar project and fear it will devalue their properties.

"I'm encouraged," said Janelle Geurts, one of the neighbors represented by Minneapolis attorney Court Anderson, who was part of a team that won a $1.8 million defamation verdict on behalf of former Gov. Jesse Ventura in 2014.

Southwest Minnesota, which NextEra identified as a prime area for solar in Minnesota, has vast areas of prime farmland. The company chose this site partly because it is adjacent to a substation, and no transmission line needs to be built. It would be the second largest solar site in the state.

Some commissioners questioned whether the rule, written decades ago for large power plants, was meant to apply to solar projects.

But Anderson said solar "is unique in that it impacts prime farmland more extensively" than power plants.

Unlike the NextEra project, Great River Energy's 2.25-megawatt solar array, called the Dickinson Solar Project, doesn't require state regulatory approval and doesn't face the same challenge.

It will serve customers of Wright-Hennepin Cooperative Electric Association, a Rockford, Minn.-based power co-op that is part owner of Great River Energy.

Both Wright-Hennepin and Great River have built other solar projects, but this is their largest.

It will replace electricity now generated by fossil fuels, the utilities said in a statement.

"This project responds to our members' interest in more renewable energy offerings and allows us to diversify our power resource mix," said Steve Nisbet, vice president of external relations and power solutions for Wright-Hennepin.

The project will have 8,360 solar panels manufactured by Heliene Inc. of Sault Ste. Marie, Ontario, and installed by Energy Concepts, based in Hudson, Wis. Construction is set to begin in late March with full commercial operation expected in early July, the utilities said.

David Shaffer • 612-673-7090 Twitter: @ShafferStrib