Understanding the Price to Compare

It is important to understand the utility's electric supply price when shopping for an electric supplier.

In the summer of 2007, the Illinois General Assembly created the Illinois Power Agency (IPA), an independent government agency, to develop and manage a new electric supply procurement process for customers of Ameren Illinois and ComEd. After overseeing the procurement of electric supply, the IPA directs the utilities to enter into wholesale electric supply contracts of various duration to purchase electric supply from different sources.

According to an annual plan developed by the IPA and approved by the ICC, Ameren Illinois and ComEd purchase the electric supply for customers who have not chosen to receive supply from an Alternative Retail Electric Supplier (ARES). In recent years, IPA-administered electric supply purchases by the utilities have occured twice a year:  once in the spring and once in the fall. The ICC has the flexibility, however, to approve a plan that would purchase electricity at different times during the year.

The utilities charge customers for the costs of purchasing electric supply, without any mark-up or profit, based on how much electricity a customer uses monthly. On your monthly Ameren Illinois bill, this charge is shown as "Purch Elec" and on your monthly ComEd bill it is shown as "Electricity Supply Charge". Ameren Illinois and ComEd customers also have the option to participate in utility real time pricing programs in which customers pay electric supply rates that vary by the hour. Like the utility's electric supply price, the utilities charge customers for the costs of purchasing electric supply, without any mark-up or profit, based on how much electricity a customers uses monthly. However, the rate varies based on when the electricity was used.

Your utility bill consists of three separate sections:

• Electric Supply includes the charges for the actual electricity you are consuming.
• Transmission Service is the charge for the transmission of that electricity from the generation source to the local distribution system.
• Distribution Service includes the charges for delivering the electricity to your home or business.

For a detailed breakdown of ComEd's current electric supply price, see the Price to Compare for ComEd.

For a detailed breakdown of Ameren Illinois' electric supply price, see the Price to Compare for Ameren Illinois.

Previous Prices to Compare: Historic Price to Compare Information for both ComEd and Ameren Illinois.