Integrys Energy (UNKNOWN:TEG.DL) announced today that its Michigan Gas Utilities subsidiary has applied for a 6% increase in natural gas rates beginning in 2014.

According to the release, Michigan Gas Utilities has filed the request to offset a variety of negative factors. At the same time that the company has felt falling sales, it has faced expensive transmission and distribution system upgrades, costlier customer service functions, and general inflation.

"Michigan Gas Utilities has long been committed to safe, reliable and affordable gas service for our customers," said President Barbara Nick in a statement. "This rate adjustment will allow us to continue our efforts to modernize portions of our system that are aging."

The company last requested a distribution rates increase in January 2010  and, according to Nick, Michigan Gas has been "extremely prudent" in its budgeting over the last three years.

Michigan Gas currently serves around 166,000 customers who, if the increase is approved, would feel an average $2.34 bump in their monthly bills. The release notes that, even after the proposed increase, cheaper natural gas prices would put customer costs at around 75% of their 2010 levels.