Wind Resource Evaluation: PEAMS 50m Tower Site

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OREGON ANEMOMETER LOAN PROGRAM

Wind Resource Evaluation: PEAMS 50m Tower Site

Prepared By:

Energy Resources Research laboratory Oregon State University

September 23, 2008

NOTICE This publication was prepared as an account of work sponsored by the Energy Trust of Oregon, Inc. Neither the Energy Trust of Oregon, Inc. nor any of their contractors, subcontractors, or their employees make any warranty, express or implied, or assume any legal liability or responsibility for the accuracy, completeness, usefulness, or reliability of the research data, and conclusions reported herein, or of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. For these reasons and for the reason that the views, opinions, and conclusions contained in this material are those of the contractor.

Wind Resource Evaluation: PEAMS 50m Tower Site

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OREGON ANEMOMETER LOAN PROGRAM

Wind Resource Evaluation: PEAMS 50m Tower Site

Prepared by: Philip L. Barbour Stel N. Walker, Ph.D. Energy Resources Research Laboratory Department of Mechanical Engineering Oregon State University Corvallis, OR 97331

Sponsor: Energy Trust of Oregon, Inc. 733 SW Oak Street, Suite 200 Portland Oregon,97205

Wind Resource Evaluation: PEAMS 50m Tower Site

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Wind Resource Evaluation: PEAMS 50m Tower Site

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1.0

SITE DESCRIPTION Site Name: Latitude: Longitude: Elevation: County: Tower Height: Types of Sensors: Instrumentation: Types of Data:

Installation Date: Data Available to:

PEAMS 50m 45-28.844 (WGS 84) 120-46.374 2217 ft. Sherman 50 meter NRG Maximum #40 wind speed NRG 200 series2 wind vane 49m (161 ft.) – Wind Speed (2), Wind Direction 40m (131 ft.) – Wind Speed 30m ( 99 ft.) – Wind Speed, Wind Direction 10 min. average wind speed (mph) 10 min. mean wind direction (deg) 10 min temperature (Deg F) Standard Deviation, maximum and minimum over 10 min. period also available for each data type. June 28, 2007 July 22, 2008

Site Location: This property is in north-central Oregon about one mile south of Gordon Ridge and roughly 3 mile west of the town of Moro. The property consists of rolling hills separated by canyons and most of the area is used as farm land. The area slopes slightly down to the north before rising to Gordon Ridge. The terrain is open and the site is well exposed. The tower location is marked on the map included in Appendix A. Project Description: The owners are interested in persuing a small community oriented wind project.

Wind Resource Evaluation: PEAMS 50m Tower Site

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2.0

WIND DATA PROCESSING

NRG equipment was used at this site including #40 anemometers and a Symphony data logger. Data chips were swaped out on roughly a monthly basis by a nearby land owner and sent to the ERRL. Raw NRG Symphony files were read and downloaded from the data cards. NRG Symphony software was used to read these files and produce monthly files of ten minute averages. These files were then converted to hourly averages and converted to an internal ERRL format to accommodate data checking and to perform analysis using existing programs. In this process each level/site combination is assigned a two digit site code. Theses codes are listed in Table 1. Table 1: Site codes and information for the PEAMS 50m site location. Site ID

Latitude

Longitude

Elev.

dd-mm-ss

dd-mm-ss

(ft)

PEAMS 50m

45-28-51

120-46-22

2217

161

P2

PEAMS 50m

45-28-51

120-46-22

2217

131

June 2007 - July 2008

P3

PEAMS 50m

120-46-22

2217

99

June 2007 - July 2008

P1

Site Name

45-28-51

Sensor Ht (ft)

Period of Record

June 2007 - July 2008

In addition to the filter available for use with the NRG Symphony software, data files were also scanned manually to identify any additional periods in which ice was might be present and to identify any additional problems. Several significant and sustained icing periods were detected primarily during the months of November and December 2007 and A few isolated periods were also observed in January and February and 2008.

Wind Resource Evaluation: PEAMS 50m Tower Site

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Recovery Rate (%)

Data Recovery 100 90 80 70 60 50 40 30 20 10 0

P1 P2 P3

JUN

JUL AUG SEP OCT NOV DEC JAN

FEB MAR APR MAY JUN

JUL

Figure 1: Data recovery for the 3 levels of the PEAMS 50m site.

Wind Resource Evaluation: PEAMS 50m Tower Site

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3.0

WIND CHARACTERISTICS

In the following sections, several characteristics of the winds at the Morrow County 50 m site are examined and discussed. The goals are to evaluate the characteristics that can help explain the physical processes at work at the site and to highlight the properties that are important to assessing the wind energy potential. These evaluations are done using hourly averaged means that have been constructed using the 10 minute means recorded at the site. This is done so that existing analysis programs can be used and is not expected to have any appreciable influence on the interpretation of data. Plots of various quantities are included in this section and more complete tables can be found in Appendix B. This analysis is also confined to a single annual period. This is done so that the results are not biased by the addition of data from only a single season or a portion of a year. The period analyzed here is for July 1, 2007 to June 30 2008. Monthly Means: Table 2: Monthly Mean Wind Speed Values and data recovery rates for the annual study period.

P1 (161') Rec. (%)

P2 (133') (mph)

Rec. (%)

P3 (98')

Month

(mph)

JUL AUG SEP OCT NOV DEC JAN FEB MAR APR MAY JUN

17.0 15.5 15.6 11.5 11.6 15.9 14.2 14.1 14.3 14.6 16.7 17.8

100.0 100.0 100.0 100.0 88.2 89.4 95.3 98.1 99.5 100.0 100.0 100.0

16.8 15.3 15.4 11.3 11.8 15.6 13.8 13.8 14.0 14.4 16.5 17.6

100.0 100.0 100.0 100.0 74.6 89.1 94.9 98.3 100.0 100.0 100.0 100.0

16.2 14.8 14.9 11.0 10.9 14.8 13.0 13.2 13.4 13.6 15.7 16.6

100.0 100.0 100.0 100.0 89.3 88.7 96.9 96.7 100.0 100.0 100.0 100.0

ANN

14.9

97.5

14.8

96.4

14.1

97.6

Wind Resource Evaluation: PEAMS 50m Tower Site

(mph)

Rec. (%)

4

Diurnal Means:

Diurnal Wind Speed 25 Wind Speed (mph)

Annual 20

July

15

Jan

10 5 0 0

400

800

1200

1600

2000

2400

Hour of Day

Figure 2: Diurnal mean wind speed values for the 49 m level of the PEAMS 50 meter Site.

Frequency Distribution:

Speed Frequency Dist. 7 PEAMS 50m

Frequency (%)

6 5 4 3 2 1 0 0

5

10

15

20

25

30

35

40

45

50

Wind Speed Category (mph) Figure 3: Wind speed frequency distribution for the 49m of the PEAMS 50 meter Site.

Wind Resource Evaluation: PEAMS 50m Tower Site

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Wind Rose:

PEAMS 50m 20

Wind Speed (mph)

18 16 14 12 10 8 6 4 2 0 N

NE

E

SE

S

SW

W

NW

CALM

Direction Category

PEAMS 50m 30

Frequency (%)

25

20

15

10

5

0 N

NE

E

SE

S

SW

W

NW

Direction Category

Figure 4a-b: Frequency (%) and average wind speed (mph) for each of 16 wind direction categories from the 49m level of the PEAMS 50 meter Site.

Wind Resource Evaluation: PEAMS 50m Tower Site

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JULY

JANUARY 25

20 18

PEAMS

PEAMS

20

Wind Speed (mph)

Wind Speed (mph)

16 14 12 10 8 6

15

10

5

4 2

0

0 N

NE

E

SE

S

SW

W

NW

N

CALM

NE

E

SE

S

W

NW

CALM

JULY

JANUARY 50

18 16

45

PEAMS

PEAMS

40

14 12

Frequency (%)

Frequency (%)

SW

Direction Category

Direction Category

10 8 6 4

35 30 25 20 15 10

2

5

0

0 N

NE

E

SE

S

SW

W

NW

N

NE

Direction Category

E

SE

S

SW

W

NW

Direction Category

Figure 5a-d: Frequency (%) and average wind speed (mph) for each of 16 wind direction categories for the months of January and July from the 49m level of the PEAMS 50 meter Site.

Wind Resource Evaluation: PEAMS 50m Tower Site

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4.0

CLIMATOLOGICAL ANALYSIS

Measurements taken over a single one-year period can provide a good estimation of the winds and wind energy potential of a site. However, this is a fairly limited period and is only meaningful if we can place the period into a larger climatological context. The difficulty with this is usually finding appropriate long-term sites to base this on. For the current site there are several long-term moitoring sites in the general area. All are part of the long-term BPA wind monitoring network. These include Sevenmile Hill and Goodnoe Hills. The location and site information for these sites are shown in Table 3. The long-term normals are taken using different periods from the different sites. The wind speed departures show that the winds at both of these sites were above normal for the period between July 2007 to June 2008. Table 3: Monthly mean and departures for winds at the BPA Sevenmile Hill wind site. Sevenmile 50' Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Ann

Mean (mph) 2007‐2008 22.2 20.9 19.8 11.1 9.9 11.1 11.5 13.6 15.1 16.6 21.3 23.3 16.4

Normal (mph) 1978‐2008 21.3 19.7 16.0 12.5 10.0 9.6 10.3 10.2 13.1 15.6 18.9 20.2 15.0

Sevenmile Dep (%) 4.2 6.1 23.8 ‐11.2 ‐1.0 15.6 11.7 33.3 15.3 6.4 12.7 15.3 9.1

100' Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Ann

Wind Resource Evaluation: PEAMS 50m Tower Site

Mean (mph) 2007‐2008 23.2 21.7 20.7 11.7 10.4 11.8 12.1 14.1 15.7 17.2 22.1 24.5 17.1

Normal (mph) 1990‐2008 22.7 21.0 17.5 13.8 10.9 10.5 10.5 10.8 13.6 16.4 19.3 21.7 15.9

Dep (%) 2.2 3.3 18.3 ‐15.2 ‐4.6 12.4 15.2 30.6 15.4 4.9 14.5 12.9 7.5

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Table 4: Monthly mean and departures for winds at the BPA Goodnoe Hills wind site. Goodnoe 195' Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Ann

Mean (mph) 2007‐2008 17.3 16.1 16.4 13.6 11.5 15.0 14.4 15.4 16.1 16.9 16.4 18.6 15.6

Normal (mph) 1980‐2008 16.6 15.5 14.0 13.3 13.2 11.7 12.9 12.7 14.2 16.1 16.7 17.2 14.6

Dep (%) 4.2 3.9 17.1 2.3 ‐12.9 28.2 11.6 21.3 13.4 5.0 ‐1.8 8.1 7.1

Wind Resource Evaluation: PEAMS 50m Tower Site

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5.0

SITE POWER CHARACTERISTICS

In order to evaluate the wind power potential at this site a number of quantities were computed using the collected wind data. As with the wind characteristics, hourly wind data was used to complete this work. The power density calculation requires air density. This is estimated assuming a standard atmosphere and the site elevation. The computed quantities include the monthly mean and recovery rate of the hourly values, the maximum one hour average, the available power, the frequency that the wind was observed within a wind speed range (12 mph to 60 mph) and the shear coefficient (alpha). These quantities are shown in Table 5 and reveal a number of things about the potential for generating energy at the site. Table 5: Observed and computed power quantities for the PEAMS 50 meter Site. Values shown are for the 49m (161 ft.) and 30m (99 ft.) levels. The last three columns are for the 49m level.

161 ft.

99 ft.

Time in Shear

Month

Mean

Recovery

Mean

Recovery

(mph)

Rate (%)

(mph)

Rate (%)

Factor

Max 1-Hr (mph)

Range

Available

(12-60)

Energy

mph (%) KWh/m**2

Jul

17.0

100.0

16.2

100.0

0.093

38.5

72.4

285

Aug

15.5

100.0

14.8

100.0

0.083

37.3

63.0

252

Sep

15.6

100.0

14.9

100.0

0.087

38.6

66.5

232

Oct

11.5

100.0

11.0

100.0

0.084

37.6

37.8

119

Nov

11.6

85.3

10.9

86.4

0.118

36.5

41.9

114

Dec

15.9

89.4

14.8

88.7

0.144

47.9

61.8

303

Jan

14.2

95.3

13.0

96.9

0.174

40.5

55.4

211

Feb

14.1

99.1

13.2

96.7

0.132

47.0

55.6

186

Mar

14.3

99.5

13.4

100.0

0.131

38.3

56.6

199

Apr

14.6

100.0

13.6

100.0

0.129

36.5

58.8

191

May

16.7

100.0

15.7

100.0

0.121

37.4

66.3

314

Jun

17.8

100.0

16.6

100.0

0.134

38.5

73.9

331

ANN

14.9

97.8

14.0

97.9

0.119

47.9

59.3

2743

Wind Resource Evaluation: PEAMS 50m Tower Site

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Available Energy 350 300

KWh/m**2

250 200 150 100 50 0 Jul

Aug

Sep

Oct

Nov Dec

Jan

Feb Mar

Apr May

Jun

Figure 6: Monthly available power for 49m level of the PEAMS 50 m site.

ENERGY ROSE 45

Norm. Available Energy (% of Annual)

40 35 30 25 20 15 10 5 0 N

NE

E

SE

S

SW

W

NW

Direction Category

Figure 7: Annual Energy Rose for the 49m level at the PEAMS site.

An analysis program was run to evaluate the energy that could be produced by four separate wind turbine types. To do this, an analysis program was run that adjusts the site Weibul distribution using the shear coefficient (alpha) calculated from the hourly values (from 99 ft. to 161 ft.). Density variations are approximated using the site elevation and a standard atmosphere. Four wind turbine types are shown for reference. Table 6 Wind Resource Evaluation: PEAMS 50m Tower Site

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compares the gross capacity factors for each month for the four wind turbines. Net capacity factor estimates would account for array losses, availability losses, electric line and transmission losses, yaw, turbulence, control, blade soiling, icing and high wind cycling. While these losses would be dependent upon the design of the wind farm, a general estimate is that these losses could be in the range of eleven to fifteen percent. Table 6: Gross monthly and annual capacity factors for five wind turbine types. Lower Level (99') Mean (mph)

Upper Level (165')

%

Mean (mph)

%

Vestas 80

GE 70.5

Nordex 90 Nordex 80 Souzlon 88

2000 kW

1500 kW

2300 kW

2500 kW

2000 kW

Jul

16.2

100.0

17.0

100.0

0.370

0.371

0.403

0.316

0.418

Aug

14.8

100.0

15.5

100.0

0.313

0.314

0.341

0.269

0.351

Sep

14.9

100.0

15.6

100.0

0.314

0.315

0.343

0.266

0.354

Oct

11.0

100.0

11.5

100.0

0.152

0.149

0.167

0.126

0.171

Nov

10.9

86.4

11.6

85.3

0.165

0.158

0.182

0.136

0.188

Dec

14.8

88.7

15.9

89.4

0.331

0.325

0.359

0.291

0.370

Jan

13.0

96.9

14.2

95.3

0.281

0.270

0.305

0.240

0.321

Feb

13.2

96.7

14.1

99.1

0.249

0.242

0.273

0.213

0.284

Mar

13.4

100.0

14.3

99.5

0.266

0.259

0.290

0.224

0.302

Apr

13.6

100.0

14.6

100.0

0.277

0.270

0.303

0.233

0.317

May

15.7

100.0

16.7

100.0

0.365

0.363

0.397

0.322

0.407

Jun

16.6

100.0

17.8

100.0

0.410

0.407

0.445

0.362

0.459

Ann

14.0

97.9

14.9

97.8

0.293

0.288

0.319

0.251

0.330

Hub Heights are 80m except for GE (210 ft.)

Wind Resource Evaluation: PEAMS 50m Tower Site

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Summary, 1)

No problems were detected in the data for this site that might hinder an interpretation of the collected data.

Some icing was detected during the

winter months and removed from the records prior to performing the analyses presented here. 2)

The measured shear coefficient between the 30 meter and 49 meter levels was 0.119 on an annual basis. This is similar to that found at other towers in the region.

3)

Winds varied some with season but not widely. Winds were strongest in the summer months but energy producing winds are possible during the windter months as well.

4)

Computed gross capacity factors for four sample wind turbine types were found in a range between 25 % and 33 %. Estimates of the net capacity factors would be somewhat lower.

5)

A comparison with wind data from a nearby long-term wind monitoring site indicated that the wind observed over the analysis period (July 2007 to June 2008) were between 7-9% above the expected long-term mean although several individual months varied significantly.

Wind Resource Evaluation: PEAMS 50m Tower Site

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Appendix A: Topographic map of the general area in which the PEAMS 50m site is located.

Wind Resource Evaluation: PEAMS 50m Tower Site

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Appendix B: Photographs of Site. View of 50m Tower looking south from Gordon Ridge.

Wind Resource Evaluation: PEAMS 50m Tower Site

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Appendix C: Miscellaneous analysis Tables. STATION – Peams 50m (P1 – 49m) WIND SPEED FREQUENCY DISTRIBUTION WITH NORMALIZED AVAILABLE ENERGY DATA PERIOD OF RECORD 7/2007 - 6/2008 NORMALIZATION PERIOD - ONE YEAR AVERAGE WIND SPEED FOR PERIOD: 14.9 MPH NORMALIZED AVAILABLE ENERGY: 2748.6 KWH/M**2/YEAR TOTAL HOURS OBSERVED: 8568 SPD MPH 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48

HOURS/ PERIOD 0 40 103 127 180 275 311 393 416 490 443 480 452 441 410 404 375 334 304 285 283 283 240 218 208 203 152 144 135 105 83 66 43 38 27 23 10 15 9 6 5 2 0 1 1 0 3 1 1

RELFREQ 0.00 0.47 1.20 1.48 2.10 3.21 3.63 4.59 4.86 5.72 5.17 5.60 5.28 5.15 4.79 4.72 4.38 3.90 3.55 3.33 3.30 3.30 2.80 2.54 2.43 2.37 1.77 1.68 1.58 1.23 0.97 0.77 0.50 0.44 0.32 0.27 0.12 0.18 0.11 0.07 0.06 0.02 0.00 0.01 0.01 0.00 0.04 0.01 0.01

CUMHRS 8568 8568 8528 8425 8298 8118 7843 7532 7139 6723 6233 5790 5310 4858 4417 4007 3603 3228 2894 2590 2305 2022 1739 1499 1281 1073 870 718 574 439 334 251 185 142 104 77 54 44 29 20 14 9 7 7 6 5 5 2 1

CUMRELFREQ 100.00 100.00 99.53 98.33 96.85 94.75 91.54 87.91 83.32 78.47 72.75 67.58 61.97 56.70 51.55 46.77 42.05 37.68 33.78 30.23 26.90 23.60 20.30 17.50 14.95 12.52 10.15 8.38 6.70 5.12 3.90 2.93 2.16 1.66 1.21 0.90 0.63 0.51 0.34 0.23 0.16 0.11 0.08 0.08 0.07 0.06 0.06 0.02 0.01

NORMALIZED AVAIL. ENERGY KWH/M**2/YEAR 0.0 0.0 0.0 0.2 0.6 1.8 3.5 7.1 11.2 18.7 23.2 33.5 40.9 50.8 59.0 71.5 80.5 86.0 92.9 102.4 118.6 137.3 133.9 139.0 150.7 166.2 140.0 148.5 155.3 134.2 117.4 103.0 73.8 71.6 55.6 51.7 24.4 39.8 25.9 18.7 16.8 7.2 0.0 4.2 4.5 0.0 15.3 5.4 5.8

Wind Resource Evaluation: PEAMS 50m Tower Site

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Wind Resource Evaluation: PEAMS 50m Tower Site

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0.0 0 14.2 709

0.0 0 14.1 683

FEB 0.0 0 14.3 740

MAR 0.0 0 14.6 720

APR

0.0 0 13.8 706

0.0 0 13.8 684

FEB 0.0 0 14.0 744

MAR 0.0 0 14.4 720

APR

2007 # OBS 2008 # OBS

0.0 0 13.0 721

JAN 0.0 0 13.2 673

FEB 0.0 0 13.4 744

MAR 0.0 0 13.6 720

APR

MONTHLY WIND SPEEDS (MPH) DATA PERIOD OF RECORD 6/2007 -

0.0 0 15.7 744

MAY

7/2008

0.0 0 16.5 744

MAY

7/2008

STATION – Peams 50m (P3 – 30m)

2007 # OBS 2008 # OBS

JAN

MONTHLY WIND SPEEDS (MPH) DATA PERIOD OF RECORD 6/2007 -

0.0 0 16.7 744

MAY

7/2008

STATION – Peams 50m (P2 – 40m)

2007 # OBS 2008 # OBS

JAN

MONTHLY WIND SPEEDS (MPH) DATA PERIOD OF RECORD 6/2007 -

STATION – Peams 50m (P1 – 49m)

13.8 73 16.6 720

JUN

14.2 73 17.6 720

JUN

14.1 74 17.8 720

JUN

16.2 744 15.2 517

JUL

16.8 744 16.0 517

JUL

17.0 744 16.2 517

JUL

14.8 744 0.0 0

AUG

15.3 744 0.0 0

AUG

15.5 744 0.0 0

AUG

14.9 720 0.0 0

SEP

15.4 720 0.0 0

SEP

15.6 720 0.0 0

SEP

11.0 744 0.0 0

OCT

11.3 744 0.0 0

OCT

11.5 744 0.0 0

OCT

10.9 643 0.0 0

NOV

11.8 537 0.0 0

NOV

11.6 635 0.0 0

NOV

14.8 660 0.0 0

DEC

15.6 663 0.0 0

DEC

15.9 665 0.0 0

DEC

13.83 14.37

4328 4839

AVG

15.14

4835

# OBS

14.47

4225

AVG

15.38

4833

# OBS

14.54

AVG

4326

# OBS

7.13

7.09

SD

7.42

7.40

SD

7.48

7.49

SD

Wind Resource Evaluation: PEAMS 50m Tower Site

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15.2 15.2 12.8 12.4 16.2 14.0 14.9 12.9 13.0 10.3 13.1 15.7

15.0 15.0 13.5 12.6 15.6 14.1 14.8 11.6 13.2 10.5 12.7 15.9

14.3 15.1 14.0 12.9 14.4 13.1 12.8 11.0 13.7 11.2 12.7 14.7

600 14.6 14.0 13.7 12.3 13.1 12.9 11.5 11.2 13.0 10.8 12.6 15.1

700

800

900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 2200 2300 2400

13.6 11.8 13.7 11.7 13.4 13.0 11.8 11.3 12.4 10.2 12.8 15.3

12.9 11.7 13.3 12.3 13.7 13.6 11.6 10.7 12.8 10.2 11.8 15.5

12.6 11.5 13.0 13.6 13.4 14.8 12.2 11.3 13.2 11.3 10.7 16.1

12.5 12.1 12.9 14.7 13.6 15.2 12.8 12.6 13.9 10.9 11.8 16.2

12.5 13.0 13.7 14.9 14.8 16.5 13.5 13.8 14.6 11.0 11.6 16.8

13.3 12.7 14.6 14.9 15.6 18.1 15.4 15.3 15.4 11.2 11.8 15.5

13.3 13.5 15.1 16.5 16.5 19.8 17.2 16.1 16.4 12.6 11.9 15.2

14.0 14.0 16.2 17.5 17.9 21.1 19.1 17.6 17.6 13.9 11.0 14.9

13.2 14.8 17.6 18.2 18.7 21.8 21.0 19.0 18.3 14.8 11.7 15.4

13.5 15.0 17.3 18.3 19.1 21.8 21.2 19.6 19.2 14.5 11.3 15.9

15.2 16.9 16.5 18.2 19.0 21.4 21.3 20.4 19.2 13.7 10.4 15.4

15.3 17.6 15.8 17.5 19.2 21.7 21.6 20.5 19.7 13.8 10.1 16.7

15.8 15.9 14.9 16.6 19.9 21.8 21.4 19.9 19.1 12.0 10.5 15.7

15.2 14.4 14.0 15.6 19.6 22.8 21.0 19.5 18.2 11.1 10.3 16.9

15.1 13.9 13.5 14.0 19.0 22.2 20.8 18.2 17.2 10.7 11.9 16.3

14.7 13.3 12.8 13.8 19.0 21.0 20.9 17.2 16.3 10.4 11.2 16.2

14.8 13.6 12.9 13.5 17.7 18.6 19.7 16.5 15.5 10.6 11.2 16.4

14.6 14.4 14.1 13.8 13.7 13.3 12.9 12.6 12.5 12.8 13.3 13.9 14.5 15.4 16.3 17.1 17.3 17.4 17.6 17.0 16.6 16.1 15.6 15.1

15.1 15.5 13.6 12.5 16.3 14.8 15.6 14.8 13.5 9.7 12.4 15.8

500

AVG SPD

14.8 13.9 13.8 12.3 16.8 16.2 17.2 15.2 14.2 10.1 11.5 16.5

400

13.8 13.6 13.9 12.3 17.5 16.9 18.8 15.3 14.6 10.5 10.5 17.6

300

JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC

200

100

6/2008

MON

DIURNAL WIND SPEEDS (MPH) DATA PERIOD OF RECORD 7/2007 -

STATION – Peams 50m (P1 – 49m)

14.9

14.2 14.1 14.3 14.6 16.7 17.8 17.0 15.5 15.6 11.5 11.6 15.9

AVG SPD

Wind Resource Evaluation: PEAMS 50m Tower Site

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NOTE:

N NNE NE ENE E ESE SE SSE S SSW SW WSW W WNW NW NNW CALM TOTAL %

DIR

19 TO 22

7.5

0.0 0.0 0.0 0.1 0.1 0.0 0.0 0.0 0.0 0.1 0.7 0.3 1.0 2.9 2.3 0.0

22 TO 25

5.4

0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.4 0.2 0.5 2.5 1.5 0.0

25 TO 28

3.4

0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.2 0.1 0.3 1.9 0.7 0.0

28 TO 31

1.5

0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.1 0.0 0.2 0.7 0.3 0.0

31 TO 34

0.6

0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.1 0.2 0.1 0.0

34 TO 37

0.3

0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.1 0.0 0.0

37 TO 40

0.1

0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

40 TO 43

0.1

0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

43 TO 46

0.0

0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

46 TO 49

0.0

0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

49 TO 52

0.0

0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

52 TO 55

0.0

0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

>= 55

100.0

0.9 0.9 1.1 2.9 9.8 2.6 1.3 0.6 1.6 2.5 7.1 7.9 12.0 24.6 21.5 2.7 0.0

TOTAL %

14.9

5.9 6.5 9.4 10.3 11.3 8.8 6.8 6.7 8.5 15.5 15.7 13.7 14.8 18.6 16.8 9.5

MEAN SPEED (MPH)

MEAN SPEED OF THE TOTAL IN A WIND ROSE MAY DIFFER FROM THE SPEED FREQUENCY DISTRIBUTION FOR A GIVEN PERIOD DUE TO DATA SELECTION. SPEED FREQUENCY DISTRIBUTIONS REQUIRE ONLY A WIND SPEED OBSERVATION BE PRESENT. WIND ROSES, ON THE OTHER HAND, REQUIRE BOTH SPEED AND DIRECTION BE PRESENT FOR EACH OBSERVATION.

9.8

16 TO 19

29.9 16.0 14.2 11.3

0.0 0.0 0.1 0.5 2.1 0.2 0.0 0.0 0.0 0.2 1.0 1.4 2.1 3.0 3.3 0.3

13 TO 16 0.0 0.0 0.0 0.1 0.3 0.0 0.0 0.0 0.1 0.1 1.0 0.9 0.9 3.4 3.0 0.1

0.1 0.1 0.1 0.5 2.6 0.7 0.2 0.0 0.2 0.2 1.2 1.6 2.1 3.1 3.0 0.4

10 TO 13 0.0 0.0 0.0 0.1 1.1 0.1 0.0 0.0 0.0 0.1 0.8 0.9 1.4 3.0 3.6 0.1

0.8 0.7 0.7 1.6 3.7 1.7 1.1 0.5 1.3 1.2 1.8 2.4 3.3 3.6 3.7 1.7

0 TO 10

SPEED CATEGORIES(MPH)

WIND ROSE FOR ALL DATA 8568 OBSERVATIONS DATA PERIOD OF RECORD - 7/2007 - 6/2008

STATION – Peams 50m (P1 – 49m)

Wind Resource Evaluation: PEAMS 50m Tower Site

20

26.1

95.7

13.1

5.8 1.9 0.5 1.5 0.0 0.0 0.2 0.1 0.5 0.9 1.0 0.5

ESE

3.4

0.8 0.9 0.3 0.0 0.0 0.3 0.0 0.2 0.1 0.5 0.1 0.2

SE

1.3

0.2 0.3 0.1 0.0 0.0 0.0 0.0 0.1 0.1 0.0 0.1 0.3

SSE

17.8

6.5 0.0 0.3 0.0 0.0 0.1 0.0 0.6 0.0 0.6 0.4 9.3

S

140.0

31.2 2.2 2.9 0.7 0.0 0.0 0.0 0.0 0.0 0.6 2.0 100.3

SSW

210.8

54.6 18.7 17.8 6.0 0.0 1.5 0.1 0.0 2.1 20.7 25.2 64.0

SW

162.1

27.2 32.5 17.0 8.9 0.6 12.6 0.7 0.4 2.6 25.8 15.9 17.9

WSW 15.3 46.0 72.3 85.1 215.5 175.0 121.3 111.1 116.6 31.1 23.6 36.8

WNW

320.5 1049.8

33.1 47.5 39.9 27.2 14.1 25.2 9.4 9.0 20.9 9.2 22.3 62.7

W

666.9

9.1 16.0 41.5 52.9 76.1 104.0 143.9 120.3 74.1 19.3 5.9 3.7

NW

AVAILABLE ENERGY IN AN ENERGY ROSE MAY DIFFER FROM THE SPEED FREQUENCY DISTRIBUTION FOR A GIVEN PERIOD DUE TO DATA SELECTION. SPEED FREQUENCY DISTRIBUTIONS REQUIRE ONLY A WIND SPEED OBSERVATION BE PRESENT. ENERGY ROSES, ON THE OTHER HAND, REQUIRE BOTH SPEED AND DIRECTION BE PRESENT FOR EACH OBSERVATION.

10.9

13.9 18.4 4.9 5.9 6.1 4.1 3.2 2.4 5.6 7.6 17.3 6.3

E

NOTE:

2.1

6.3 1.1 1.3 1.8 0.9 1.9 2.9 1.1 6.0 1.5 0.4 1.0

ENE

1.4

7.4 0.1 0.0 0.1 0.3 0.1 0.4 0.1 1.3 0.4 0.0 0.6

NE

TOT

0.0 0.0 0.0 0.1 0.1 0.0 0.2 0.2 0.8 0.5 0.0 0.1

NNE

0.0 0.0 0.0 0.0 0.2 0.0 0.2 0.3 0.4 0.0 0.1 0.0

N

JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC

MON NORM.

ENERGY ROSE (TOTALS ARE NORMALIZED AVAILABLE ENERGY (KWH/M**2) DATA PERIOD OF RECORD 7/2007 - 6/2008

STATION – Peams 50m (P1 – 49m)

20.5

0.1 0.1 0.4 0.8 1.8 6.6 2.5 6.7 0.8 0.4 0.1 0.1

NNW

2742.5

211.5 186.0 199.4 191.3 315.8 331.5 285.0 252.4 232.0 119.2 114.4 303.9

TOTAL

8567

709 683 740 720 744 720 744 744 719 744 635 665

OBS.

8760

744 672 744 720 744 720 744 744 720 744 720 744