Illinois policymakers have been working to replace closing coal plants with renewable energy sources, particularly wind and solar power. However, this transition didn’t unfold as planned in 2023. Instead, natural gas, another fossil fuel, filled the gap.
Despite ongoing efforts to move away from fossil fuels, electricity production from renewables declined in Illinois and surrounding Midwest states last year. This drop occurred even as they continued to push for renewable energy sources like wind and solar to replace coal and natural gas.
A Surprising Setback for Wind Energy
In 2023, wind power, which is Illinois’ primary source of renewable energy, saw an unexpected 6% decline in electricity generation, while electricity produced from natural gas spiked by 43%, according to government data.
One major factor behind this shift was an unusual weather pattern, driven by a high-pressure system in Canada. The same system contributed to the wildfires that brought smoky skies to Chicago in the summer. This pressure system also altered wind patterns, reducing the amount of wind available to power the nearly 300-foot turbines scattered across Illinois.
“Small changes in wind speed can have significant impacts on wind power generation,” noted Jessica Conroy, an associate professor of earth science and environmental change at the University of Illinois. Conroy and her doctoral student, Allison Wallin, have been researching wind speed trends over the past 30 years to understand how these shifts might affect wind energy moving forward.
The Need for Better Forecasting
With climate change in mind, scientists like Conroy believe it’s crucial to use future wind projections to plan for renewable energy. For more than a decade, researchers have debated whether climate change—the driving force behind the push for renewable energy—might itself influence wind patterns.
As developers increasingly shift their focus toward solar power, which saw growth in Illinois last year, wind energy still plays a key role in replacing fossil fuels. Though solar power’s share remains small, it is growing rapidly. Meanwhile, coal generation dropped by a third, while nuclear energy, the state’s largest power source, saw a slight decline of 1%.
One reason for the increased reliance on natural gas was the completion of the Three Rivers Energy Center, a 1.2-gigawatt gas-fired power plant southwest of Chicago. This one plant added nearly as much power capacity as all the new utility-scale wind and solar projects combined in 2023.
Unusual Winds in 2023
The winds in Illinois were unusual last year, slowed by a “very strong high-pressure system” over Canada, according to Illinois State Climatologist Trent Ford. For much of early summer, winds blew in an unusual east-to-west direction, rather than the typical west-to-east pattern. This shift brought wildfire smoke into Illinois and contributed to lower wind speeds.
At O’Hare Airport, the average wind speed from June to August 2023 was only 8 miles per hour, the lowest recorded since 2009. Data collected over the past two decades also show that wind speeds last year were considerably lower than the average, Ford said. He has been collaborating with Conroy and Wallin to examine these trends and their potential long-term impact on wind energy.
A Growing Concern: Slower Winds
Though wind speeds naturally fluctuate from year to year, researchers have observed a more significant decline over time, raising concerns that climate change may be a factor. Different regions may experience varying effects, but the Midwest, with its vast wind farms, is an important area for study.
Michael Craig, a professor at the University of Michigan, emphasized the need for long-term planning in the energy sector. “For a system planner, you have to consider multiple years of weather data—10, 20, or even 30 years—before making investment decisions,” Craig said. This helps account for variability and ensures that renewable energy systems remain efficient over time.
The Future of Illinois Energy
Illinois is aiming to eliminate fossil fuels from its energy mix by 2050, with two major energy laws providing financial support to aging nuclear plants while incentivizing both solar and wind power. Wind remains the largest source of renewable energy in Illinois and plays a critical role in reducing dependence on coal, a significant contributor to global warming.
However, the dip in wind energy last year offset gains from other renewable sources, resulting in a nearly 3% overall decline in renewable electricity generation. Advocates, however, see potential in solar energy, which currently provides only 2% of the state’s electricity but has been growing rapidly.
“We definitely need more solar,” said J.C. Kibbey, a climate adviser to Illinois Governor J.B. Pritzker. Kibbey highlighted solar’s dramatic growth in recent years and expressed confidence in the long-term trend for wind energy, despite the 2023 decline.
Long-Term Optimism for Wind Energy
Billions of dollars have been invested in wind farms across the U.S., especially in the Midwest. While some clean energy advocates downplay the importance of a single-year decline, wind developers are eager for more research to better understand future wind trends.
Wind energy in Illinois has experienced similar drops in previous years, notably in 2016 and 2018, when a combination of slower wind speeds and limited new wind farm developments led to reduced energy generation. Jeff Danielson, vice president of advocacy for Clean Grid Alliance, reassures that one year’s results don’t define a trend.
State officials aim for continuous growth in renewable energy generation, but as reliance on wind and solar increases, so does the need to manage variability in weather patterns. Craig, the University of Michigan professor, stressed that the natural fluctuations in wind speeds should not deter future investments in wind power.
“This isn’t a crisis,” Craig said. “We need more wind, and we need more solar.”