Deregulation in the state actually began with natural gas in the 1980s. Gas is much easier to view as a commodity, since it actually has substance as opposed to electricity, not to mention it gets traded on commodity exchanges.
However, after businesses were first given the opportunity to switch electricity suppliers in the mid-1990s, competition still remained somewhat limited since most of the companies switching were only the largest businesses.
In 2007, however, the Illinois state legislature mandated that utility companies cooperate with retail electricity providers to simplify the billing process for people who switch. That move brought in many more companies and encouraged thousands more residents and businesses to make the switch.
In the Commonwealth Edison service area alone there are 41 different electricity providers, while the Ameren service area offers 18 different options, according to PlugInIllinois. Crain's notes ComEd reports around 27 percent of small businesses in its area have now chosen to switch, with this wealth of new options.