In 2024, Illinois experienced an unprecedented boom in solar energy, adding 2.5 gigawatts of new capacity—nearly doubling its existing output. This growth made Illinois one of the top-performing states in solar expansion, behind only California, Florida, and Texas. But 2025 is bringing new political and economic challenges that could threaten the pace of progress.
A budget reconciliation bill pushed by Republicans in the U.S. House of Representatives—titled “One Big Beautiful Bill” and backed by former President Donald Trump—aims to roll back nearly all clean energy incentives introduced under the Inflation Reduction Act (IRA) of 2022. Among its proposals is the immediate end to the federal tax credit for residential solar systems, which was originally set to phase out gradually by 2034.
The Solar Energy Industries Association, along with research firm Wood Mackenzie, estimates that removing these incentives could result in a 25% drop in solar installations by 2035. While this poses a nationwide risk, Illinois’ environmental advocates believe the state can weather the storm thanks to local laws and programs already in place.
The foundation of Illinois’ clean energy push is the Climate and Equitable Jobs Act, passed in 2021, which set the goal of reaching 100% carbon-free energy by 2050. As of May 2025, Illinois has 4.6 gigawatts of installed solar capacity and another 6.1 gigawatts in development—together, more than six times the output of the state’s largest coal-fired power plant.
Much of this growth comes from state-backed programs like Illinois Shines, which incentivizes both rooftop and community solar projects, and Illinois Solar for All, which helps low- and moderate-income households adopt solar energy. These programs are funded through state energy job acts and a federal grant from the EPA’s Solar for All initiative. According to Samira Hanessian of the Illinois Environmental Council, community solar in particular has been a success story. She notes that while other renewables like nuclear may take decades to build, solar can be deployed far more quickly and affordably.
Still, Illinois solar advocates faced a major disappointment when the state legislature failed to pass the Clean and Reliable Grid Affordability Act during the spring 2025 session. The bill would have supported grid modernization, energy storage, and a new virtual power plant program. Will Kenworthy of Vote Solar called the missed opportunity a setback, but noted there was consensus around many parts of the proposal—leaving room for another push during the fall veto session.
Meanwhile, Illinois Shines continues to move forward, currently offering financing for 800 megawatts of solar capacity across multiple project types. Thanks to the 2016 and 2021 energy job laws, funding for renewable energy has grown significantly—from $235 million to over $580 million annually. A recent forecast suggests there could be a funding shortfall by 2028, but the Illinois Power Agency says resources remain sufficient for now. Hanessian believes the state’s renewable portfolio standard (RPS)—the policy used to measure Illinois’ clean energy progress—is still on track.
Yet, financial resources aren’t the only issue. Soaring demand for electricity—driven by the rapid growth of data centers—has placed added pressure on grid capacity. At the same time, many solar projects are stuck in long queues waiting for grid interconnection.
Chicago-based Windfree Solar, founded in 2009, has seen solar adoption evolve dramatically over the years. What began as small pilot projects for schools quickly turned into full-scale residential and commercial installations. Founder Doug Snower credits the federal solar incentives for helping the company reach middle-income households. He warns that repealing those incentives could hurt residential sales, but sees long-term opportunity in commercial and community solar. “Between now and 2050, there will be community solar no matter what,” he said.
Despite the looming threat of federal rollbacks, Illinois appears determined to stay the course. Environmental leaders like Tucker Barry of the Illinois Environmental Council argue that state-level action is more important than ever. “The [Trump] bill would cut all we accomplished with the Inflation Reduction Act,” Barry said. “This is where we have the chance to make progress at this point.”
Source: Inside Climate News