Renewal for Illinois EV plates is this year. $35 for two more years. It happens in the odd years. You cannot renew on line, you either have to mail in a check or go to one of the offices. More than likely you received a letter, or will get one soon. If you purchased EV plates recently, the letter might not show up.
In past years the branch DMV offices didn't carry the EV stickers. That may have changed in the past two years. I do know for certain the office on Elston in Chicago has them, they are a full service office.