Montana

• Owned generation resources supplied approximately 75% of our retail load requirements in 2015.
• Our remaining customer load requirements are met with market purchases from third parties and include resources from wind generation, gas-fired generation and qualifying facilities.
• 60% of our generation came from wind and water in 2015. Only 28% came from owned thermal resources and the remainder came from thermal (natural gas and coal) that is under contract.
• In 2014, we completed the purchase of 10 hydroelectric generating facilities in Montana.
• Our Dave Gates Generating Station at Mill Creek, a 150 MW natural gas fired facility, primarily provides regulation service for the transmission system. 

 South Dakota

• Our South Dakota electric supply load requirements are primarily provided by three jointly owned coal-fired generating plants:     
• We also own several peaking/standby generating units located throughout our service territory including a 52 MW unit in Aberdeen, S.D. that was placed into service in 2014.
• We purchased and placed into service in 2015 the 80 MW Beethoven Wind Project located near Tripp, S.D.
• We use market purchases and peaking generation to provide peak supply in excess of our base-load capacity.
• In 2015, 75% of the electricity utilized in South Dakota came from coal and 25% from owned and contracted wind projects.