12/11/20091

Wyoming Pipeline AuthorityHappy Jack Wind Farm

December 10, 2009

12/11/20092

Black Hills Corporation

Utilities Non-Regulated Energy

Gas UtilitiesColorado Natural GasIowa Natural GasKansas Natural GasNebraska Natural Gas

Electric UtilitiesBlack Hills PowerCheyenne Light, Fuel & Power *Colorado Electric

CoalWyodak Resources

Oil & GasBlack Hills Exploration & Production

Power GenerationBlack Hills Electric Generation

Energy MarketingEnserco Energy

Fuel, Generation, and Utilities

An integrated and diversified energy company

* Supplies electric and gas utility service to Cheyenne, Wyoming and parts of Laramie County

12/11/20093

BHC Non-RegulatedCalgary

Golden

Operation Summary *• Doing business in 10 states and Calgary, Alberta, Canada• Oil and gas wells in Powder River Basin, Piceance Basin and

San Juan Basin• 186 Bcfe reserves – 83% natural gas & 17% oil• 141 MW IPP capacity• Approximately 274 million tons of low-sulfur Powder River Basin

coal for low-cost, mine-mouth electricity generation• Energy marketing has been a profitable business every year

since inception

Power generation

Gas production

Oil production

Coal mine

Energy marketing

* Information as of 12/31/2008

12/11/20094

BHC UtilitiesUtilities Operation Summary*•759,400 total customers•6.0 million MWH annual electric sold•54.6 million Dth annual natural gas sold•92.8% generation availability•630 MW net generation capacity

Gas Operations HQ (Omaha)Cheyenne Light

WY

CO

NE

KS

IA

Black Hills PowerSD

MT

Nebraska GasIowa Gas

Kansas Gas

Colorado Gas

Colorado Electric

Customer Service Center (Rapid City)

Customer Service Center (Lincoln)

Electric Operations HQ (Rapid City)

Customer Service Center (Cheyenne)

Natural Gas Operations HQ (Omaha)

Gas services

Electric services

* Information as of 12/31/2008

12/11/20095

Cheyenne Light Fuel & Power

Operation Summary:•1882 Brush Swan Electric Co.•38,000 Electric Customers•34,000 Natural Gas Customers•1,200 sq mi service territory•1 million MWH Annual Electric •4.5 BCF Annual Core NG Sales (transport gas addt’l 8.8 BCF)

•New peak load of 176 MW set on Dec 14, 2008

Cheyenne Light

WY

* Plants owned by our non-regulated power generation subsidiary

Generation assets:Coal: 95 MW (Wygen II)Coal: 60 MW (Wygen I* PPA)Gas: 40 MW (Gillette CT #2* PPA)Wind: 25 MW (Happy Jack & Silver Sage Wind Farms * PPA)

12/11/20096

Happy Jack Wind Farm• Owned and operated by

Duke Energy• Cheyenne Light, Fuel &

Power & Black Hills Power have a 20 year purchase power agreement

• 14 wind turbines (2.1 MW)• Happy Jack Wind Farm

capacity – 14 x 2.1 = 29.4 MW

• Can produce 100 million kWh each year

12/11/20097

Silver Sage Wind Farm• Owned and operated by Duke

Energy. Commercial Operation Date -Oct. 1, 2009

• Cheyenne Light, Fuel & Power and Black Hills Power have 20 year purchase power agreement for 30 MW

• 20 wind turbines • Each turbine is rated at 2.1

MW• Silver Sage Wind Farm

capacity – 20 x 2.1 = 42 MW

12/11/20098

Happy Jack/Silver Sage Wind Farms• Wind turbine dimensions

– Tower: 260 ft– 3 Blades Horizontal Axis

• Blade: 145 ft• Diameter: 290 ft• Rotational speed- 15rpm• Blade tip speed- 159

mph

– Making tip of blade over 400 ft

12/11/20099

Happy Jack/Silver Sage Wind Farms• Cheyenne Wind Data

– Average annual wind speeds of 15-18 mph

– 37-40 % capacity factor

• Wind speed specifications– Cut in wind speed: 9

mph– Rated wind speed: 31

mph– Cut out wind speed: 55

mph

12/11/200910

Wind Turbine InformationPower Curve

0

500

1000

1500

2000

2500

9 11 13 16 18 20 22 25 27 29 31 34 36 38 40 43 45 47 49 51 54 56

Wind Speed (mph)

Po

wer

Ou

tpu

t (k

W)

12/11/200911

12/11/200912

Challenges Facing Renewables

• High initial capital costs

• Geographic limitations

• Intermittent / Variable nature

• Transmission availability and cost

• Environmental and aesthetic challenges (NIMBY)

12/11/200913

CLF&P Peak Load Profile 14 December 2008

0

20

40

60

80

100

120

140

160

180

200

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

TIME [HR] 

LOAD

 [MW

]

CLF&P PEAK LOAD [MW]

CLF&P Peak Load Profile14 December 2008 

0

20

40

60

80

100

120

140

160

180

200

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

TIME [HR] 

LOAD

 [MW

]

CLF&P PEAK LOAD [MW]

WYGEN 2 [MW]

CLF&P Peak Load Profile 14 December 2008

0

20

40

60

80

100

120

140

160

180

200

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

TIME [HR] 

LOAD

 [MW

]

CLF&P PEAK LOAD [MW]

BHW WYGEN 1 [MW]

WYGEN 2 [MW]

CLF&P Peak Load Profile14 December 2008

0

20

40

60

80

100

120

140

160

180

200

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

TIME [HR] 

LOAD

 [MW

] CLF&P PEAK LOAD [MW]

PURCHASE FROM BHP [MW]

BHW WYGEN 1 [MW]

WYGEN 2 [MW]

CLF&P Peak Load Profile 14 December 2008

0

20

40

60

80

100

120

140

160

180

200

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

TIME [HR] 

LOAD

 [MW

]

CLF&P PEAK LOAD [MW]

HJ WIND FARM [MW]

PURCHASE FROM BHP [MW]

BHW WYGEN 1 [MW]

WYGEN 2 [MW]

12/11/200914

CLF&P June Peak Load ProfileCLFP Resources for June 2009 Peak Day

80

90

100

110

120

130

140

150

160

170

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Hour

MW

CLFP HJ Output

Economy Purch.

Wygen 1 used forload

Wygen 2

June Peak 158 MWHappy Jack Output .33 MW

12/11/200915

Happy Jack Wind FarmAverage August vs December MWh Production by Hour

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

1:00 A

M3:0

0 AM

5:00 A

M7:0

0 AM

9:00 A

M11

:00 AM

1:00 P

M3:0

0 PM

5:00 P

M7:0

0 PM

9:00 P

M11

:00 PM

Hour

MW

h Pr

oduc

ed

Average August MWhAverage December MWhRated MWh

12/11/200916

Happy Jack Wind FarmDecember 5, 2008 MWh Production by Hour

0

5

10

15

20

25

30

1:00 A

M3:0

0 AM

5:00 A

M7:0

0 AM

9:00 A

M11

:00 AM

1:00 P

M3:0

0 PM

5:00 P

M7:0

0 PM

9:00 P

M11

:00 PM

Hour

MW

h Pr

oduc

ed

December 5, 2008 MWh

12/11/200917

Happy Jack Wind FarmDecember 24, 2008 MWh Production by Hour

0

5

10

15

20

25

30

1:00 A

M3:0

0 AM

5:00 A

M7:0

0 AM

9:00 A

M11

:00 AM

1:00 P

M3:0

0 PM

5:00 P

M7:0

0 PM

9:00 P

M11

:00 PM

Hour

MW

h Pr

oduc

ed

December 24, 2008 MWh

12/11/200918

Happy Jack Wind FarmAugust 15, 2009 MWh Production by Hour

-

5

10

15

20

25

30

1:00 A

M3:0

0 AM

5:00 A

M7:0

0 AM

9:00 A

M11

:00 AM

1:00 P

M3:0

0 PM

5:00 P

M7:0

0 PM

9:00 P

M11

:00 PM

Hour

MW

h Pr

oduc

ed

August 15, 2009 MWh

12/11/200919

Happy Jack Wind FarmAugust 19, 2009 MWh Production by Hour

-

5

10

15

20

25

1:00 A

M3:0

0 AM

5:00 A

M7:0

0 AM

9:00 A

M11

:00 AM

1:00 P

M3:0

0 PM

5:00 P

M7:0

0 PM

9:00 P

M11

:00 PM

Hour

MW

h P

rodu

ced

August 19, 2009 MWh

12/11/200920

Percentage of Generation during Peak Hours (4PM-7PM)

10%11%12%13%14%15%16%17%18%19%20%

Sep-08

Oct-08

Nov-08

Dec-08

Jan-09

Feb-09

Mar-09

Apr-09

May-09

Jun-09

Jul-09 Aug-09

Sep-09

Month

On

Peak

Pro

duct

ion

[%]

On Peak Production (4PM-7PM)

12/11/200921

Public Opposition

• NIMBY – Not In My Back Yard• NIABY – Not In Anyone’s Back Yard• BANANA – Build Absolutely Nothing

Anywhere Near Anyone• CAVE – Citizens Against Virtually Everything

12/11/200922

Summary

• Contrary to public perception, the wind doesn’t always blow in Wyoming:– Majority of Wind Farm generation is produced during off-

peak times– Peak Period generation (4pm-7pm) – approximately 13%– Demonstrates continued need for base load generation

• We support a diverse energy portfolio that includes coal (the primary generation fuel for our company and for the U.S.) natural gas, wind, solar, biomass and hydro.

12/11/200923

Questions?

Contact Information

Mark StegeVice President, Operations Cheyenne Light Fuel and Power108 W. 18thCheyenne, WY 82001307-778-2101

www.blackhillscorp.com