Black Hills Corporation Announces Commercial Operation of the Valencia Power Plant

RAPID CITY, S.D., June 4 /PRNewswire-FirstCall/ -- Black Hills Corporation today announced that the Valencia Power Plant near Albuquerque, NM was placed into commercial service on May 30, 2008.

The Valencia facility is a 149 megawatt gas-fired power plant under a tolling contract to provide energy and capacity to Public Service Company of New Mexico (PNM). This plant is part of the Company's pending sale of independent power generation plants to affiliates of Hastings Funds Management Ltd and IIF BH Investment LLC, a subsidiary of an investment entity advised by JPMorgan Asset Management announced April 30, 2008 and expected to close in late second quarter or early third quarter 2008. Under the terms of the sale agreement, the Valencia power plant is required to be in commercial operation as specified by the tolling agreement with PNM.

David R. Emery, Chairman, President and CEO of Black Hills Corporation, said, "Our power generation and corporate development teams did an outstanding job of getting the Valencia power plant sited, built and operating ahead of schedule and below the projected construction cost of $101 million. Valencia was constructed, tested and brought into service in less than a year -- a commendable effort in an industry which has significant regulatory oversight as well as shortages of labor and materials. We are pleased to be serving the energy needs of PNM and its customers.

"We excel in planning, permitting, constructing and operating reliable and efficient power plants, and Valencia is the latest demonstration of our capabilities." Emery concluded, "With this accomplishment, we now turn our attention to the completion of Wygen III, a 100 megawatt mine-mouth coal-fired power plant expected to be in service in 2010."

ABOUT BLACK HILLS CORPORATION

Black Hills Corporation is an integrated energy company. Our utilities are Black Hills Power, an electric utility serving western South Dakota, northeastern Wyoming and southeastern Montana; and Cheyenne Light, Fuel & Power, an electric and gas distribution utility serving the Cheyenne, Wyoming vicinity. Black Hills Energy, the non-regulated energy business unit, generates electricity, produces natural gas, oil and coal, and markets energy. More information is available at our Internet web site: http://www.blackhillscorp.com/.

CAUTION REGARDING FORWARD-LOOKING STATEMENTS

This news release includes "forward-looking statements" as defined by the Securities and Exchange Commission, or SEC. We make these forward-looking statements in reliance on the safe harbor protections provided under the Private Securities Litigation Reform Act of 1995. All statements, other than statements of historical facts, included in this release that address activities, events or developments that we expect, believe or anticipate will or may occur in the future are forward-looking statements. These forward-looking statements are based on assumptions which we believe are reasonable based on current expectations and projections about future events and industry conditions and trends affecting our business. However, whether actual results and developments will conform to our expectations and predictions is subject to a number of risks and uncertainties that, among other things, could cause actual results to differ materially from those contained in the forward-looking statements, including the risk factors described in Item 1A of Part I of our 2007 Annual Report on Form 10-K filed with the SEC, Item 1A of Part II of our March 31, 2008 Quarterly Report on Form 10-Q, and the following:

-- Our ability to complete the construction, start up and operation of power generating facilities in a cost-effective and timely manner; -- Our ability to complete divestitures and acquisitions for which definitive agreements have been executed; -- Our ability to obtain favorable regulatory rulings when we seek to add power generation assets into our rate base; -- Other factors discussed from time to time in our other filings with the SEC.

New factors that could cause actual results to differ materially from those described in forward-looking statements emerge from time to time, and it is not possible for us to predict all such factors, or the extent to which any such factor or combination of factors may cause actual results to differ from those contained in any forward-looking statement. We assume no obligation to update publicly any such forward-looking statements, whether as a result of new information, future events, or otherwise.