PAYNESVILLE - As soon as the January sun popped out from behind the clouds, the green computer-generated graph line at Louis Industries soared up in a sharp peak.

At the same time, the graphics depicting the amount of money made and trees saved also changed.

“Did you see that?” said Leo Louis, president and CEO of the Paynesville steel processing facility, as he eagerly pointed to a sudden spike in the amount of solar power produced by the 1,200 solar panels on the roof of the family-owned plant.

“We are producing more than we are using,” Louis said. “We are using 143 kilowatts and we produced 153.”

In November, Louis Industries activated more than an acre of solar panels on the roof of their business in Paynesville’s industrial park.

Done in partnership with Xcel Energy, it’s anticipated the 498-kilowatt solar array will produce about 625,000 kilowatt-hours of energy per year.

In a 30-day timeframe during the bleak, relatively sunless winter, Louis Industries produced only about 7.6 megawatts of solar power, which was about 12 percent of the total electricity used in that period.

Louis is eager to watch his graphic solar display this summer when it’s put through its first season of full sun.

“Oh, gosh. This is going to be fun,” Louis said, who anticipates an investment payback in seven years.

“This could be the best business decision I ever made,” he said.

According to Louis, his rooftop system was the second largest solar array in the state when it was installed last summer. It’s currently about the sixth largest.

“But it won’t be for long,” he said.

A variety of incentives - federal tax credits, the Made in Minnesota program, Xcel Energy’s capacity credit - and the rapid decrease in price of solar panels that made the project financially attractive to his business mean more solar arrays will be starting up soon in Minnesota, he said.

David Winkelman, from Innovative Power Systems - the St. Paul-based company that installed the solar array, said the project with Louis Industries was a “game-changer” in part because it pushed Xcel Energy to prepare their system to purchase even more privately generated solar power.

“There are a host of projects that are coming through, especially community solar gardens,” Winkelman said. “The solar industry is now a real player.”

In a news release, Chris Clark, regional president of Xcel Energy, praised the cooperative project with Louis Industries.

“Our customers are increasingly interested in clean energy options that are efficient, and we’re committed to providing them with more options to achieve their own energy goals,” Clark said.

Louis said he had considered investing in wind power as an alternative energy source for his business, but said the incentives, decreased cost of solar arrays and lack of maintenance costs compared to wind turbines made it clear that “now is the time” to invest in solar energy.

Louis said more businesses - especially those with plenty of flat, empty roof space - should consider investing in their own solar array as a way to offset their energy costs and potentially earn revenue from selling excess power.

Winkelman said Innovative Power Systems is developing rooftop solar array projects with several other area businesses, including a manufacturer in Belgrade and three neighboring businesses in the Paynesville industrial park that may share a solar array system. He’s also developing a proposal with the New London-Spicer School District that could include a partnership with investors.

“Hopefully in another 20 years every flat roof will be covered,” Winkelman said.

Technically, Louis Industries does not use its own solar-generated electricity. Instead, it flows to an Xcel transformer, which feeds electricity back to Louis Industries. Some days, Louis Industries produces and sells more energy than it needs.