Ameren IllinoisCo. plans to file for an approximately $14 million decrease in its deliveryservice rates for 2017.

The Ameren Corp.subsidiary expects to file its request with the Illinois Commerce Commission byApril 15. It will be the fourth such rate decrease in the years since the EnergyInfrastructure Modernization Act was passed in 2011, according to an April 6 release.

"The smart grid legislation is working exactly as designed,"Craig Nelson, senior vice president of regulatory affairs and financial servicesfor Ameren Illinois. "It's giving us the regulatory certainty to make much-neededenhancements to an aging energy infrastructure, while providing customers with morereliable service."

If approved by Illinois regulators, new rates would go into effectbeginning January 2017.

In addition, Ameren Illinois gas customers will also see a discountin April as natural gas market prices continue to remain low. A nearly 4-cent dropin the per-therm cost of natural gas is expected to save most customers $28 annuallyor $2.35 a month, the utility said.