IL HB1563

Defines "underground" or "undergrounding" as routing and constructing electric transmission lines and associated components below ground consistent with sound engineering practices.

Requires public utilities to underground any 138 kilowatt or greater electric transmission lines constructed after the bill's effective date in two specified scenarios: within 26,000 feet of airports in municipalities of 70,000-80,000 population in counties exceeding 1,000,000 inhabitants, or in 4 or more contiguous municipalities with population density of 1,000 per square mile or greater.

Directs the Illinois Commerce Commission to allow public utilities to recover all reasonable and prudent undergrounding costs from all retail customers across their entire service territory, rather than solely from affected municipalities.

Requires public utilities to record undergrounding costs as a regulatory asset in their rate base and amortize the costs over a period equal to the expected life of the transmission line.

Takes effect immediately upon becoming law.