MANKATO — John Sacco wasn’t thinking about fighting global warming two years ago when he spent $14,000 to install more efficient lighting at his Mankato factory.

Sacco wasn’t motivated by a desire to help Xcel Energy meet its government-mandated efficiency improvements either. And he wasn’t anticipating the day when his Mankato metal fabrication factory would be swarming with politicians and media and environmentalists.

Sacco is a businessman, and his focus was on the bottom line.

A lighting contractor, working on a nearby business, had spied — through an open bay door — the lighting system in Sacco’s AmeriStar facility in the industrial park north of Highway 14.

The contractor walked into the factory and told Sacco he should tear the existing lights out and put new ones in. Sacco asked why he would do that when the lighting was only 5 years old.

“He said, ‘Well, you could save money,’” Sacco said Tuesday. “And that’s when my ears perk up.”

The new system is actually producing more light while reducing Sacco’s electrical bill by about $4,000 a year. About 70 percent of AmeriStar’s customers are outside the state, meaning the business is competing with metal fabricators from around the country and world.

“Keeping your costs down is so important in keeping competitive,” Sacco said.

So AmeriStar reduced its overhead on overhead lighting, but the project has those side benefits that drew lawmakers, city officials and environmentalists to a tour and news conference Tuesday. It reduces greenhouse gases by an estimated 180,000 pounds. And it does help Xcel Energy meet its state-required 1.5 percent annual reduction in electricity consumption.

“It’s a case study of what we need to do nationwide,” said Michael Noble of Fresh Energy, a St. Paul-based nonprofit organization pushing for a transition to a cleaner, more efficient energy system.

Fresh Energy and the Izaak Walton League organized the tour and press conference, hoping to draw attention to Minnesota’s energy-efficiency laws at a time when Congress is considering major revisions in the nation’s energy policy. Under the 2007 state energy reform — passed with overwhelming support from both Democrats and Republicans — power companies are required to reduce by 1.5 percent annually the use of the product they sell.

That means incentives for projects like the one at AmeriStar, which cost $27,800 before Xcel’s $13,560 rebate.

And that means jobs for companies such as The Retrofit Companies, an Owatonna firm that installs highly efficient lighting systems. Retrofit President Steve Kath said his company started in a small office in the business incubator in Owatonna in 1992, had grown to eight workers when it moved into its own space 15 months later, and now has 63 employees.

Retrofit has branch offices in Little Canada and Indianapolis and has done projects across the country, including a trio of jobs that cost over $1 million in Manhattan, Alaska and Minneapolis.

“I truly believe it’s a win-win for pretty much everybody,” Kath said of mandates to push the nation toward more efficient energy use. “... They’re saving money. We’re putting people to work.”

State Sen. Ellen Anderson, a St. Paul Democrat and one of the Senate’s leading environmentalists, said the Minnesota energy-efficiency standard is about much more than reduction in pollution. The standard is making Minnesota companies more efficient — and helping them in a global marketplace where other nations are more aggressively pursuing reductions in energy waste.

“That’s the secret to the 21st century,” Anderson said. “... And it’s happening right here in Mankato. Congratulations.”