Welcome to Chicago, the Windy City, which has officially flipped the switch to 100% renewable energy for all its municipal buildings as of January 1, 2025! Over 400 facilities, from fire stations to international airports, are now powered entirely by sunshine.

This remarkable transformation is largely facilitated by the Double Black Diamond Solar Farm, the largest solar installation east of the Mississippi River. Spanning 3,800 acres in central Illinois, this solar powerhouse is set to provide approximately 70% of the city’s electricity needs. This shift is projected to slash Chicago’s carbon footprint by around 290,000 metric tons each year, equivalent to taking 62,000 cars off the road!

The seeds for this ambitious plan were sown nearly a decade ago when former Mayor Rahm Emanuel set a vision for carbon-free energy sourcing back in 2017. Fast forward to 2022, and current Mayor Lori Lightfoot struck a game-changing deal with Constellation to purchase energy from Swift Current Energy. This five-year, $422 million agreement not only powers the city but also fuels local economic growth through job training initiatives and an expected $100 million boost in tax revenue for surrounding counties.

While Chicago will initially cover the remaining 30% of its energy needs through renewable energy credits, city officials have their eyes set on cultivating local clean energy sources in the future. But what is Chicago’s ultimate goal? To power all buildings in the city with renewable energy by 2035, making Chicago the largest U.S. city to achieve this milestone.