ComEd wants to hike power rates by eight percent, but opponents yesterday stepped in to challenge that. The fight over the rate increase could last a while.

Does ComEd deserve another 360 million dollars from its customers? It’s not just an economic issue - it’s a matter of law, actually. The Illinois Commerce Commission will decide after hearing arguments on both sides. ComEd’s says it’s built power lines in fast-growing suburbs. Plus, it claims it’s paying fifty percent more for that wire than it did a few years ago.

Opponents like the Illinois Attorney General and the Citizens Utility Board say the jump’s still not justified. CUB claims it’s studied ComEd’s books, and the company should get by with a tenth of its proposed hike.

ComEd customers could have seven months of hand-wringing in front of them; Illinois regulators will likely decide the ComEd rate increase proposal in September.

I’m Shawn Allee, Chicago Public Radio.