Illinois is among the top five U.S states for installed wind capacity, with almost 13% of our energy being generated by wind. The majority of wind farms in Illinois are located in the central and northern regions, where wind is abundant.
One of the largest wind farms in Illinois is the Twin Groves Farm, constructed in 2008 in McLean County. This project has 240 wind turbines that generate enough power for 120,000 homes. Despite its size, the wind turbines only take up 1% of the 22,000 acres of the site. The property taxes from the farm provide $300,000 a year to a nearby school district.
How does wind energy work?
Wind energy starts with the sun. The sun heats Earth’s surface unevenly due to varying terrain, oceans, and atmospheric conditions. This uneven heating causes air to move, creating wind. Warm air rushes into its place, setting air in motion. This is why there are often strong winds when there’s a sudden temperature change, like a warm day followed by a cold front.
Wind turbines generate power by converting wind into electricity. When the wind blows, it turns the blades of the turbine which spins a generator to produce power.
There are 3 types of wind energy systems
- Land-based wind: The most common type. These are what you see in open plains and hilltops where the wind is strong and consistent. They can power anything from small communities to large regions.
- Offshore Wind: These turbines are built in bodies of water, typically in oceans or large lakes. These are more expensive to build and maintain. There aren’t currently any offshore wind projects in Illinois, but there are proposals to build in Lake Michigan.
- Distributed wind: These are smaller wind turbines that can be used to generate electricity for a home, farm, or business. These are more common in rural settings.
Parts of a wind turbine
There are four main components to a wind turbine.
- Blades: Shaped like an airplane wing to catch the wind, most turbines have 3 blades which are made of fiberglass.
- Rotor: This is the hub that the blades are attached to. It spins when the blades move and transfers that spinning motion into the rest of the turbine.
- Nacelle: The large box at the top of the tower, behind the rotor. It has 3 components:
- Gearbox increases speed of rotation.
- Generator converts motion into electricity.
- Brakes and control systems for turbine safety.
- Tower: The support structure, usually made of steel.
Wind turbines are growing but will make less sound
Larger turbines generate energy at a lower cost. The Lawrence Berkeley National Laboratory found that newer wind turbines will be nearly two-thirds taller than those built a decade ago which decreases the number of turbines needed by more than half. Average sound levels will drop by 18% for neighboring homes in the future.
Even though these turbines will be larger they will still be constructed a safe distance from neighboring homes due to setback requirements.
How do wind farms affect communities?
For many communities, wind turbines are a new sight and an unfamiliar addition to the landscape. It is normal to have questions about how they might fit into your local area.
Wind farms can bring a range of local benefits, including:
- Local tax revenue to support schools, emergency services and infrastructure improvements
- Land lease payments to support local landowners, often farmers and ranchers, providing a source of stable income
- Job creation during both construction and long-term operations
- Increased energy independence by adding more diversity to the energy mix
- In some cases, local electricity generation, which may keep more energy investment within the community