A plan to provide an alternative form of energy in Wisconsin is pitting two sets of environmentalists against each other. Some favor cleaner air, others want to protect nearby wildlife.

Doug Duncan, a Wisconsin farmer who uses windmills to add to his two-turbine farm, said his crop is so good, it's encouraging neighbors to get their own windmills.

A Chicago-based energy company wants to build 133 wind turbines like Duncan's that could produce enough energy to power 100,000 homes near the city of Fond du Lac.

"Every kilowatt hour of wind actually preserves cleaner air," said Michael Vickerman of RENEW-Wisconsin (search). "[Wind energy] will have a lowering effect on electricity rates. With this project in place, rates could actually decline or at least not go up as fast."

But wildlife enthusiasts oppose the project. The reason? Birds. The turbines may be as close as a mile and a half from the Horicon Marsh (search), a federally protected wildlife preserve.

"This is a major migratory bird route here, feeding and nesting area for tens of thousands of birds. We strongly fear that lots of birds will be killed by these turbines," said Curt Kindschuh of the Horicon Marsh Systems Advocates.

A state environmental impact report has concluded that not enough evidence is available to say what kind of impact wind turbines could have on bird populations. If the project were to go forward, just 1 percent of Wisconsin's energy would be wind-generated.

Opponents say they would feel differently about the endeavor if the project were built elsewhere.

"Wind energy is good, but there is a place to put that and you don't put 133 turbines within a mile and a half of a wildlife refuge," Kindschuh said.

Farmer Dennis Oechsner said delaying alternative energy is not in order.

"It's sad to say that everybody can squawk about it and push it off to someone else, but if we keep moving it elsewhere, sooner or later, we're not going to have it," he said.

Farmers will receive more than $4,000 a year for each windmill built on their property. With times not being the best for traditional farmers, those in support of the plan call it a windfall.

Click in the box near the top of the story to watch a report by FOX News' Jeff Goldblatt.