BLACK HILLS CORP. TO ISSUE EARNINGS GUIDANCE
AND SCHEDULES WEBCAST

Black Hills Corp. Media Contact:
Lynn Wilson 605-721-2774
Media Relations Line:
866-243-9002
Investor Relations:
Jason Ketchum 605-721-2765

RAPID CITY, SD — September 10, 2008— Black Hills Corp. (NYSE: BKH) will issue a news release providing updated 2008 and initial 2009 earnings guidance on Wednesday, Sept. 17, 2008. A conference call and webcast is scheduled for 11 a.m. EDT on Thursday, Sept. 18, 2008.

The company recently completed the sale of seven independent power plants to Hastings Funds Management and IIF BH Investment and the purchase of five natural gas and electric utilities from Aquila.  New guidance will take into account the completion of these transactions and the related permanent financing plans and will also provide updated information pertinent to the Company’s other business segments.

Those interested in the live broadcast can call 800-553-0272. To access the webcast and download a copy of the investor presentation, go to the Black Hills’ Web site at blackhillscorp.com and click “Webcast” in the “Investor Relations” section. The presentation will be posted the evening before the webcast. Listeners should allow at least five minutes for registering and accessing the presentation. For those unable to listen to the live broadcast, a replay will be available by telephone through Thursday, Sept. 25, 2008 at 800-475-6701 in the United States and at 320-365-3844 for international callers. For the replay only, callers need to enter the access code 959506# when prompted.

ABOUT BLACK HILLS CORPORATION
Black Hills Corp. — a diversified energy company with a tradition of exemplary service and a vision to be the energy partner of choice — is based in Rapid City, S.D., with corporate offices in Golden, Colo., and Omaha, Neb. The company’s utilities serve 750,000 natural gas and electricity customers in Colorado, Iowa, Kansas, Montana, Nebraska, South Dakota and Wyoming. The company’s non-regulated businesses generate wholesale electricity, produce natural gas, oil and coal, and market energy. The employees of Black Hills partner to produce results that improve life with energy. More information is available at www.blackhillscorp.com.