BLACK HILLS CORP. SUBSIDIARY SELLS 23.5 PERCENT IN WYGEN I POWER PLANT TO THE MUNICIPAL ENERGY AGENCY OF NEBRASKA

RAPID CITY, S.D., January 22, 2008 — Black Hills Corp. (NYSE: BKH) today announced its subsidiary, Black Hills Wyoming, has completed the $51 million sale of 23.5 percent ownership in its Wygen I power generation facility to The Municipal Energy Agency of Nebraska (MEAN). Wygen I is an 85-MW coal-fired plant located near Gillette, Wyo.

“We are pleased to continue our longstanding partnership with MEAN and look forward to being co-owners of the Wygen I facility,” said David R. Emery, chairman, president and chief executive officer of Black Hills Corp.

The agreement with MEAN also provides payments for costs associated with administrative services, plant operations and coal supply provided by Black Hills subsidiaries during the life of the facility. MEAN previously held a 10-year power purchase agreement with Black Hills to buy 20 MW of power annually from Wygen I. The existing Wygen I power purchase agreement between MEAN and Black Hills terminated concurrent with MEAN’s purchase of the ownership interest.

“MEAN’s purchase of an interest in the Wygen I facility will benefit our wholesale customers by providing them with competitively priced energy in a transmission-constrained area for years to come,” said MEAN executive director J. Gary Stauffer.

The Black Hills and MEAN transaction also received regulatory approval from the Nebraska Power Review Board and the Federal Energy Regulatory Commission prior to the close of the transaction.

ABOUT BLACK HILLS CORP.
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 utility companies 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. Black Hills employees partner to produce results that improve life with energy. More information is available at www.blackhillscorp.com.

ABOUT MUNICIPAL ENERGY AGENCY OF NEBRASKA (MEAN)
Formed in 1981, MEAN provides wholesale power supply and energy-related services to 65 communities and one joint-action agency in four states: Colorado, Iowa, Nebraska and Wyoming. MEAN is one of four energy-related organizations of NMPP Energy, a joint-action agency headquartered in Lincoln, Neb.

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