Commonwealth Edison Co. (ComEd), Illinois’ largest electric utility, received approval from the Illinois Commerce Commission to collect an additional $155.7 million in yearly revenue from customers as part of the utility’s grid modernization plan. The rate hikes, which were approved unanimously by the commission, will increase an average electric bill from a single family by $3.15 a month, or $37.80 per year. The additional charges will be tacked on to distribution services, which means all customers who receive electric service from ComEd will see the increases, regardless of whether they buy their electricity from the utility or an alternative electric supplier . The new distribution rates will go into effect June 1 and show up on customer bills for the following billing cycle. Initially, ComEd had requested a $326.3 million increase, but the commission reduced the proposal by more than $170 million after Commission staff, the Citizen Utility Board, the Illinois Industrial Energy Consumers organization and the Illinois Attorney General recommended reductions in several areas, including operations, maintenance, incentive compensation and pension contributions. ComEd said that it opposes the Commission’s decision and that it needs the full rate increase to “recover the costs of making these [grid] investments and to continue maintaining a reliable electric delivery system.” ComEd said it’s moving forward with its “Energy Infrastructure Modernization Act,” a legislative proposal to invest $2.6 billion in Illinois’ electric grid over the next 10 years. The utility claims the investment will reduce outages and disruptions, create jobs and protect regulatory oversight. However, critics of the legislation, such as Illinois Attorney General Lisa Madigan and David Kolata, executive director of the Citizen Utility Board, argue that setting utility rates using the proposed legislation’s formula would undercut the authority of the Commission, which currently has the power to approve or deny rate increases. If passed, the legislation would add another $3 a month to residential electric bills. Sources ” ComEd Rate Hike to Cost Customers About $3.15 a Month ,” Chicago Tribune , May 24, 2011. ” ComEd Increases Yearly Rates by $155.7M ,” NBC Chicago, May 25, 2011. ” ComEd Rate Hike to Cost Customers About $37.80 More a Year ,” The Herald-News , May 25, 2011.