NorthWestern Responds to Montana Public Service Commission Potential Court Action on Colstrip 4

NorthWestern, in an effort to be open and transparent, previously announced that it was engaging in a strategic review of the value and potential options forColstrip 4. The MPSC, concerned about the future price and source of electricity for Montanans, today issued a press release indicating they will consider possible court action to stop a potential sale ofColstrip 4.

Customers are already receiving the benefit of half of NorthWestern's interest inColstrip 4 through power supply contracts that are significantly below market. Analysis to date indicates that it may not be in the customers' best interest to placeColstrip 4 in rate base. Under the current supply contracts,Montana customers are not responsible for any future, currently unknown, environmental costs related to carbon emission. These costs could be significant.

NorthWestern agrees with the MPSC that ensuring adequate and reasonably priced electric supply for itsMontana customers is a top priority. The Company wants to assure itsMontana customers that it has dedicated energy supply professionals whose focus is working to meet the current and future electric supply needs of ourMontana customers at fair and reasonable prices.

NorthWestern is disappointed in the Commission's announcement today. Colstrip 4 has never been in rate base, and in 1985 the Commission waived its authority overColstrip 4. The Company has been forthright in its discussions with the Commission regarding itsColstrip 4 process.

NorthWestern has worked hard to build positive relations with the MPSC and the citizens ofMontana. The Company remains willing to discuss the facts, but a lawsuit would be unnecessary, counter-productive and without legal basis.

The Company intends to complete its evaluation of strategic options for Colstrip 4 while providing reasonably priced and environmentally responsible power for consumers and fair and reasonable returns for our shareholders.

About NorthWestern Energy

NorthWestern Energy is one of the largest providers of electricity and natural gas in the Upper Midwest and Northwest, serving approximately 650,000 customers inMontana,South Dakota andNebraska. More information on NorthWestern Energy is available on the Company's Web site at http://www.northwesternenergy.com.

SOURCE NorthWestern Corporation