Interstate Power and Light Co. (IPL), a subsidiary of Alliant Energy Corp., rejected in a letter a request by Iowa Gov. Chet Culver to delay implementation of interim electric rates as part of the rate case filed March 10.

IPL said it would implement the interim rates on March 20.

“We appreciate your concerns on behalf of our customers as we also recognize the cost impact that any change in our electric rates can have on the customers we are privileged to serve,” said Tom Aller, IPL President in the company’s response to the Governor.

Culver said he made the request because literature sent to IPL customers made no mention that the rate increases have yet to be approved by the Iowa Utilities Board and because rate increases are coming at a time when Iowans, businesses and school districts are already struggling to balance their budgets. (View Culver’s letter)

The company is requesting to increase its electric rates in a range from 12 to 18 percent but is proposing a customer cost management plan designed to reduce the impact of the rate increase on consumers during the next several years. It would save customers a combined $90 million in the first year of the plan, according to IPL.

IPL expects a decision from the Utilities Board in early 2011. The company says that if it can reach an agreement with all involved parties, the plan could be implemented earlier.

According to IPL, it asked the governor in a letter to help bring all the involved parties together in an effort to reach a settlement.