Photo courtesy of Marshall Municipal Utilities Thousands of solar panels were installed for a 10-megawatt solar farm in the Marshall city limits. Marshall Municipal Utilities General Manager David Schelkoph said the solar farm is planned to be completed this fall. All the electricity generated by the solar farm will be used in Marshall, especially by customers like the Archer Daniels Midland plant, Schelkoph said.

MARSHALL — A 10-megawatt solar farm under construction in Marshall is getting closer to completion, said Marshall Municipal Utilities General Manager David Schelkoph.

“This fall is when they’re going to come online, probably in a September — October time frame. That’s still the plan,” Schelkoph said.

Schelkoph gave an update on the solar farm construction to members of the Marshall Noon Rotary on Tuesday.

Construction on the project began in 2023 on about 50 acres of land near North Seventh Street and Lyon County Road 33 in Marshall. Thousands of solar panels making up the solar farm are in place, and work crews are now installing power inverters needed to convert the solar energy from DC to AC power, Schelkoph said.

Construction of the solar farm has been mainly on schedule, although there were some delays on the delivery of materials, he said.

All the power generated by the solar farm will be used within the city of Marshall.

“Typically, solar farms of this size are not inside the city limits — they’re in the county area because of their size,” Schelkoph said.

The solar farm is a roughly $40 million project. Schelkoph said a big part of the expense will be the cost of lithium ion batteries, to store some of the electricity generated by the solar panels for times when the sun isn’t shining.

Of the $40 million total project cost, about $25 million is the batteries, he said.

The solar farm project is being undertaken by Missouri River Energy Services (MRES). MRES is one of two major providers of electricity for Marshall Municipal Utilities, Schelkoph said. The other provider is the Western Area Power Administration (WAPA), which is in charge of hydroelectric dams on the Missouri River system, he said.

“Marshall gets about 25% of our energy needs from hydroelectric power,” through WAPA, Schelkoph said. The remaining 75% comes from MRES.

“There’s 61 members of this organization (MRES) in four different states,” he said. “And they are the organization that are investing in building this solar plant here in Marshall.”

Of the cities that are members of MRES, Marshall uses the most electricity, Schelkoph said.

“We take about 12% of their total load, so we’re the largest member of MRES. And that’s one of the reasons why they built here, because we have a load big enough to handle the particular production of this solar farm,” he said.

Schelkoph said MRES already owns nine wind turbines located southwest of Marshall, but they were adding a solar farm for a couple of reasons. Solar panels had a relatively low cost to install, and would also help utilities meet Minnesota’s state-mandated goals for carbon-free energy.

However, solar energy does have some drawbacks, Schelkoph said.

“On average, the solar panels will produce only about 22% of the time,” he said. “So there’s the problem, right? We don’t have power long enough to keep the lights on 24/7.”

One way to help fix that problem is by having energy storage. The Marshall solar farm will have five megawatts of battery storage, Schelkoph said.

“That will last for four hours,” he said. “Now, that’s typically pretty good right now, because our peaking period in this community is about four hours long … So when we really need that energy, we can have that energy.”

The solar farm will use lithium ion batteries, that will be located in individual outdoor units.

“They’re not inside a building. It kind of helps us a lot for fire and for emergency response,” Schelkoph said.

The Marshall solar farm includes just under 21,500 solar panels, Schelkoph said. It took a crew of about 40 people 45 days to install the panels. The panels are designed to turn to catch the sun, but only along one axis, Schelkoph said.

“They’ll be at an angle, and they’ll track the sun from the morning all the way over to the evening,” he said.

Schelkoph said the solar panels will require maintenance over time. Dust or damage on the glass panels makes them less efficient at producing electricity from sunlight. MMU will have a maintenance contract with MRES for the solar farm. The panels being installed at the solar farm have a life expectancy of about 20 to 25 years, he said.

All the electricity generated by the Marshall solar farm will be used in the city of Marshall, Schelkoph said. In particular, the Archer Daniel Midland plant in Marshall would benefit from the solar power source.

“This particular plant is scaled so all of its power can go into ADM,” he said. The ADM plant uses between 30 and 40 megawatts of power, which accounts for about half of MMU’s electrical load, Schelkoph said. “They rarely go below 20 megawatts, and the only time they do is when they break down or they close down for maintenance.”

Schelkoph told the Independent it was good that MRES decided to have battery storage at the Marshall solar farm. This would help give MRES an opportunity to learn how to make the most effective use of solar energy.

“The future of energy production is balance,” Schelkoph said. Renewable energy sources also need to be reliable for customers. Not investing in storage and other ways to keep reliability in the power grid would have negative consequences, he said.

“Public policy, and political policy needs to change. We need to encourage renewable energy. But with that, we need to encourage storing energy so that we can use it beyond when the wind doesn’t blow and the sun doesn’t shine,” Schelkoph said.