Illinois Supreme Court to Decide Solar Project Siting Dispute
Illinois Supreme Court will review conflicting appellate rulings on solar project siting.
Why it matters: This ruling will clarify legal standards for local solar project approvals, impacting utilities, developers, and regulators navigating Illinois energy infrastructure development.
- On September 30, 2026, the Illinois Supreme Court agreed to review Tate Road Solar 1, LLC v. County of Winnebago.
- The Fourth District ruled counties have discretion and cannot be compelled to approve solar permits under mandamus even if statewide standards are met.
- The Third District held counties must approve solar projects that meet statutory standards and mandamus is available if permits are improperly denied.
- Conflicting appellate decisions have caused significant uncertainty for developers, landowners, counties, and lenders in Illinois.
The Illinois Supreme Court took a critical step on September 30, 2026, agreeing to hear Tate Road Solar 1, LLC v. County of Winnebago, addressing a split in appellate law over county authority in solar energy project siting.
The Fourth District Appellate Court ruled counties retain discretion in reviewing solar siting applications and cannot be compelled by mandamus to approve permits, even if projects meet requirements under Section 5-12020 of the Counties Code. In contrast, the Third District Appellate Court decided in Equity Solar Illinois v. County of Grundy that counties must approve projects meeting statutory standards and mandamus is available as a remedy where counties deny permits improperly.
This conflicting case law has unleashed industry-wide uncertainty. As noted by legal experts at ArentFox Schiff, "The conflicting decisions created substantial uncertainty for developers, landowners, counties, and lenders evaluating solar projects throughout Illinois." This uncertainty complicates due diligence, project planning, and financing for solar developments statewide.
The Illinois Supreme Court agreed to review Tate Road Solar but declined to take the Grundy County case, leaving their upcoming ruling as the definitive authority on how to interpret county responsibilities under Section 5-12020. This decision will have lasting implications on energy infrastructure legal frameworks throughout Illinois.
By the numbers:
- September 30, 2026 — Date Illinois Supreme Court agreed to review Tate Road Solar case
- Section 5-12020 — Counties Code section central to solar siting standards dispute