SOUTHERN ILLINOIS — Ameren Illinois is saying its customers in Southern Illinois should see their power bills drop some this year by about $2 a month.

Following a controversial jump in Ameren’s electricity prices in Southern Illinois last year, prices for the next 12 months should be lower because of a drop in one component of those prices.

The price paid to power plants to ensure that the grid can withstand high demand has been reduced this year because of changes in the rules governing the management of the 15-state grid.