ComEd wants another rate increase to help offset the costs of modernizing Illinois' electric grid.
The company on Wednesday filed a rate request with the Illinois Commerce Commission, asking permission to collect an addition $275 million in delivery charges. The increase would cost residential customers about $3 per month extra starting in January 2015.
The ICC has eight months to act on the request. In December it approved a rate increase allowing ComEd to collect an additional $340 million this year.
The company says it's making "strong progress" on upgrades that include switching 4 million northern Illinois customers to wireless "smart meters."
ComEd and downstate electricity provider Ameren are undertaking a 10-year, $3.2 billion project to modernize and "storm-harden" Illinois' power grid. That includes replacing aging cables and poles.