McLean County’s next wind farm project may look a little different than its predecessors.
The $350 million Sapphire Sky wind farm will be built in southeastern McLean County. Its 64 wind turbines are expected to produce enough electricity to power about 80,000 homes annually, plus $79 million in property tax revenue for local taxing bodies over the life of the project.
Sapphire Sky will also follow an industry trend toward use of taller turbines with longer blades, said David Loomis, an Illinois State University professor who has studied the economic impact of wind energy.
There are two reasons. If you build higher, the radius of the blades can get bigger, Loomis said.
“The longer the blade, the more electricity you’re going to get out,” he said.
Also, wind speeds are greater the higher you go, Loomis said. Theoretically, if you can double your wind speed, you could get as much as eight times the amount of electricity, he said.
“In the case of Sapphire Sky, they made the case that the end result will be fewer, but larger turbines,” Loomis said, noting the difference that will make on visual impact of the wind farm.
Sapphire Sky is not the only major wind farm under development. In DeWitt County just to our south, the $345 million Alta Farms Two wind farm is now under construction, with 50 turbines.
Infrastructure talks
Meanwhile, there are implications for the future of wind energy as Congress debates what will be part of the infrastructure package that President Biden has pushed, Loomis said.
A key part of Biden’s climate plan is a national “clean energy standard,” which is aimed toward zeroing out greenhouse gas emissions from the power sector by 2035. One proposal for that standard would require utilities to get 80% of their electricity from zero-emission sources by 2030 and 100% by 2035. Right now, the U.S. gets about 60% of its electricity from fossil fuels.
It’s similar to renewable energy standards in place in Illinois, which require that renewable sources (wind and solar) must make up 25% of overall electricity sales by 2025. One key difference between “clean” vs. “renewable” is that “clean” would include nuclear, Loomis said.
That might Illinois in a good position, he said, because about half of its electricity comes from nuclear power plants. That includes one in DeWitt County.
