Wind Resource Evaluation: Chehalem Mountains
OREGON ANEMOMETER LOAN PROGRAM
Wind Resource Evaluation: Chehalem Mountains
Prepared By:
Energy Resources Research laboratory Oregon State University
May 20, 2010
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.
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OREGON ANEMOMETER LOAN PROGRAM
Wind Resource Evaluation: Chehalem Mountains
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
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1.0
INTRODUCTION
The Oregon anemometer loan program was established in the fall of 2002 in order to assist landowners in the state evaluate the wind energy potential of their property. The program is funded by a grant from the Energy Trust of Oregon and is administered by the Energy Resources Research Laboratory at Oregon State University. The program involves several steps, beginning with a preliminary evaluation of the site. If estimates of the site show promise then a monitoring system is installed for a fixed duration (typically one year). The site is monitored regularly and the data processed and checked at regular intervals. Upon completion of the first year, the collected wind data is summarized and a report is prepared evaluating the wind data and the wind resource of the location. This report represents the final portion of the project and is designed to give the landowner the information necessary to make an informed choice about the role wind energy might play in their property. The report is separated in to sections with section 2.0 devoted to a description of the site, its location and the type of terrain found there. Section 3.0 includes a summary of the wind data collected during the study period including data quality checks and a characterization of the measured winds. In section 4.0 the wind data is analyzed to determine the amount of power production that might be expected from the site and to examine characteristics that might influence these estimates. This is followed in section 5.0 in which wind data from a nearby site is summarized and used to place the current study period in climatological context. A discussion and summary is then presented in section 6.0
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2.0
SITE DESCRIPTION Site Name: Latitude: Longitude: Elevation: Tower Height: Site #
Chehalem Mountains 45.354 (WGS 84) 124.989 1437 ft. 77 feet (Est.) 0602
Types of Sensors:
NRG Maximum #40 wind speed NRG 200 series 2 wind vane Single level mounted on an existing tower
Instrumentation: County: Installation Date: Data Available to:
Yamhill January 24, 2009 March 10, 2010 (Monitoring will continue until sensors are removed)
Site Location: This site is located on private property in an area known as the Chehalem Mountains. The Chehalem Mountains are a sharp, relatively long ridge line that is oriented Northwest to Southeast and is located just north of the City of Newberg in Western Oregon. The site is positioned near the highest portion of the ridge, The area consists of rural homes with isolated groves of tall trees. Project Description: The landowner is in the process of developing a small wind turbine and an anemometer was loaned to help evaluate a test unit at the site. The anemometer was installed by the landowner. Direction orientation and placement has not been verified by the ERRL. No power production data was provided for comparison. Data Collection and Processing: NRG equipment was used at this site including #40 anemometers and a Wind Explorer data logger. Data plugs were swapped out on roughly a monthly basis by the landowner. Raw NRG files were read and downloaded from the data cards and used to generate 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. Data were plotted and scanned manually to detect problems and to flag periods of suspected icing. No problems with the site have been identified that might affect the interpretation of the collected wind data.
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3.0
WIND CHARACTERISTICS
In the following sections, several characteristics of the winds at the Chehalem Mountains 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 characteristics 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. These evaluations are confined to a single annual period so that the results are not biased by the addition of data from only a particular season or a portion of a year. The period analyzed here is for February 1, 2009 to January 31, 2010.
Table 3.1: Monthly mean wind speed values and data recovery for the Chehalem Mountains site.
Month FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC JAN ANN
Site 0602 - 77' (mph) Rec. (%) 9.6 100.0 9.7 100.0 9.1 100.0 10.2 100.0 7.7 100.0 9.7 100.0 8.1 100.0 9.8 100.0 8.7 100.0 11.3 100.0 12.4 100.0 11.8 70.2 9.8
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3
Diurnal Means: The diurnal pattern of winds is an important characteristic for many wind sites and helps illuminate the mechanisms responsible for the winds. In general, a diurnal pattern is associated with a site at which strong thermal influences play a role. These are normally accentuated during the summer months when the daily heating cycle is at its greatest. Diurnal variations can also provide an indication of dependable and predictable winds at a site. For this site there is a much better defined diurnal pattern in the July data that begins to rise in the evening and peaks around 10:00 at night.
Diurnal Wind Speed - 77' 16
Wind Speed (mph)
14 12 10 8
January
6
July
4
Annual
2 0 0
400
800
1200
1600
2000
2400
Hour of Day
Figure 3.1: Diurnal mean wind speed values for the Chehalem Mountains site.
Frequency Distribution: How the wind speed at a site is distributed over various wind speed categories is an important indication of the wind resource potential of a site. An ideal site would have winds that blow at a high rate for long periods. This is not normally the case, however, and wind records from a site show a skewed distribution with a higher frequency of winds at lower speeds.
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Speed Frequency Dist. - 77' 8 7
Frequency (%)
6 5 4
3 2 1 0 0
5
10
15
20
25
30
35
40
Wind Speed Category (mph)
Figure 3.2: Wind speed frequency distribution for the Chehalem Mountains site.
Wind Rose: How the wind varies with direction is also important to understanding the physical processes that contribute to the local winds at a site and eventually in designing a wind facility. A wind rose is often used to display this information and show the frequency with which the wind occurs in different direction categories. A wind rose plot can also be used to show the strength of the wind from each of the direction categories. This is done here using color segments. Winds for the annual period as a whole are shown in Figure 3.3 and indicate the winds come from two general directions; the northnortheast (and north) and the south (and south-southwest). The strength of each of these are comparable.
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Figure 3.3: Wind rose for each of 16 wind direction categories for the annual analysis period.
In order understand better the winds at the site during different times of year; similar plots have been constructed using data from the individual months for the winter and summer. These can be seen in figures 3.4a-b and show any differences between the two periods. The winds during July and likely during the other summer months, the winds come generally from the north. The direction of the winds in March is reversed and shows strong winds from the south. March was likely a period when Pacific storms were passing through the region.
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Figure 3.4a-b: Wind rose for each of 16 wind direction categories for a winter and summer month at the Chehalem Mountain site.
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Energy Rose: In the same way a wind rose shows the strength and frequency of the wind for different direction categories, an energy rose can show the relative energy that can be expected for these same direction categories. From the wind rose it was apparent that the strongest and most frequent winds were coming from the north-northeast and south. By looking at the energy rose (Figure 3.5) it is clear that these account for nearly all of the energy producing winds at the site. As small percentage do come from other directions but the contribution is minimal. Further, from Figure 3.6 it’s clear that the bulk of the energy producing winds can be expected to occur during the winter months but that some can be expected during other months as well.
Energy Rose - Chehalem 77' Normalized Available Energy (% of Annual)
50 45 40 35 30 25 20 15
10 5 0 N
NNE
NE
ENE
E
ESE
SE
SSE
S
SSW
SW WSW
W WNW NW NNW
Figure 3.5: Percentage (%) of expected total normalized energy for each of 16 wind direction categories for the annual analysis period.
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Chehalem 77' - Percent of Annual Normalized Available Energy (% of Annual)
20 18 16 14 12 10 8 6
4 2 0 FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
JAN
Figure 3.6: Frequency (%) of expected energy for each month of the annual analysis period.
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4.0
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 mean and standard deviation of the hourly values, the recovery rate, the maximum one hour average, the wind power density and the frequency that the wind was observed within a wind speed range (12 mph to 60 mph). These quantities are shown in Table 4.1. Table 4.1: Observed and computed power quantities at the Chehalem Mountains site. Site 0602 - 77' Shear Factor Month FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC JAN ANN
(mph) 9.6 9.7 9.1 10.2 7.7 9.7 8.1 9.8 8.7 11.3 12.4 11.8
Rec. (%) 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 70.2
0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1
9.8
97.5
0.1
Time in Range (12- Available Max 1-Hr 60) Energy (mph) mph (%) kWh/m**2 26.0 32.7 64 28.7 30.2 82 23.6 25.1 58 24.5 34.9 71 23.6 20.8 42 23.1 31.2 65 20.6 18.4 41 24.6 29.3 67 24.6 25.4 59 33.5 39.6 111 30.4 47.7 151 34.2 47.1 116 34.2
31.5
916
The values in Table 4.1 reveal a number of things about the potential for generating energy at the Chehalem Mountains site. First, it is clear that there is some potential for generation during each month but the potential is lower during the summer months. The lowest month was August when the winds blew in a typical operating range less than 20% of the time. The highest was during December 2009 and January 2010. These months were a little abnormal for this period as the Northwest was under the influence of an El Nino pattern that directed much of the storm activity to the south. The result appeared to be strong north-northeast winds at this site. In addition to evaluating these basic power characteristics it is possible to estimate how specific wind turbines might interact with the winds at a particular site. Using the collected wind data and the characteristics of a particular wind turbine it is possible to
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estimate the amount of power it could produce. This is done by comparing the wind data with a power curve for a specific wind turbine. A power curve is simply the curve that shows the relationship between the wind speed and the amount of power a turbine can produce. An example is provided in Figure 4.1. There are several portions of the curve that are important. At low wind speeds, below the cut-in speed, no energy is produced. Any turbine has a lower threshold below which it won’t operate. This is in part because there is little energy available at these levels. In the middle is a ramp up zone where even a small increase in wind speed results in a larger increase in power. At some point, depending on the type of turbine, the amount of power that is generated reaches the rated limit of the generator (rated capacity). The blades are then pitched to spill energy and protect the generator. At the upper end, energy production will stop if the winds reach a cut-out speed. This is the speed at which a turbine is shut down to protect the structural integrity of the turbine. In Table 4.2, energy capacity factors are shown for five different types of turbines. The capacity factor is the ratio of the amount of energy produce to the amount of energy that could be produced if a turbine ran at its rated capacity all the time. The rated capacity is effectively a theoretical maximum and capacity factors generally range from 0.0 to 0.40. It’s difficult to compare these because of the different turbine characteristics but they are given to provide a range of values that might be expected from this site. In computing these values, it is necessary to adjust the observed data which are measured at 77 feet to the hub height of the particular turbine. In this case this is done using a standard assumption that the wind follows a typical power law profile. To do this a shear coefficient must be used. A value of 0.100 is used here. These particular turbines are likely larger than would be used at this site but should still provide an indication of the resource for the site.
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120
Power Output (% of Rated)
100
80
60
40
20
0 0
10
20
30
40
50
Wind Speed (mph)
Figure 4.2: Sample power curve for a theoretical turbine The capacity factors in Table 4.2 support the indications provided by the wind data statistics. The capacity factors for August are the lowest (0.078) and are highest for December (0.239) and January (0.195). The overall gross capacity factors range from 0.112 to 0.159. While these are relatively low for any commercial site they do suggest a limited potential at the location.
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Table 4.2: Gross capacity factors computed for various wind turbines using the Chehalem Mountains site and a shear coefficient of 0.100. Site 0602 - 77' Month FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC JAN ANN
GE 70.5
Nordex 80 Souzlon 88
Vestas
Northwind
PS600
100
(mph) 9.6 9.7 9.1 10.2 7.7 9.7 8.1 9.8 8.7 11.3 12.4 11.8
Rec. (%) 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 70.2
1500 kW 0.127 0.139 0.107 0.128 0.074 0.116 0.069 0.122 0.104 0.189 0.252 0.196
2500 kW 0.106 0.117 0.088 0.106 0.061 0.096 0.057 0.101 0.087 0.160 0.215 0.165
2000 kW 0.153 0.162 0.129 0.157 0.090 0.141 0.085 0.145 0.125 0.219 0.288 0.230
600 kW 0.121 0.134 0.102 0.123 0.071 0.112 0.067 0.116 0.100 0.178 0.236 0.186
100 kW 0.131 0.095 0.112 0.137 0.082 0.124 0.078 0.125 0.107 0.182 0.239 0.195
9.8
97.5
0.134
0.112
0.159
0.127
0.136
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5.0 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 following table shows monthly mean wind speeds, long-term normals and wind speed departures at the Salem Airport. This is a National Weather Service site and has been in place for a number of years. This comparison suggests the winds during this monitoring period overall (February 2009 - January 2010) were slightly below normal (5.6%). During several months there were significant departures including December 2009 when the winds were 17.7% below normal and January 2010 when the winds were 23.6 % below normal. There are significant due to the higher wind potential during these months. Although the winds were lower at the airport is expected that these conditions may have actually resulted in higher winds in the Chehalem Mountains due to the elevation difference. This winter period was somewhat different than usual and is attributed to the presence of an El Nino in the Pacific. Although the area has received normal rainfall amounts there have been fewer strong storms affecting the region. Conditions were also mild and may have resulted in fewer southerly wind storms in the area. However, this was not tested explicitly. The lower than normal winds observed at the Salem Airport for August do show that the weaker winds observed at the Chehalem mountains tower might have been somewhat anomalous and somewhat higher winds might be expected during these months for other periods. Table 5.1: Monthly means for the current observation period, long-term normals and departures for the current annual period. Salem McNary Field - NWS Current 2000-2009 Departure Month (mph) (mph) (% ) FEB
4.4
5.8
-24.4
MAR
7.9
7.1
10.9
APR
6.0
6.5
-8.0
MAY
6.3
6.0
5.6
JUN
5.8
6.3
-7.8
JUL
5.5
6.3
-12.5
AUG
5.1
5.8
-12.8
SEP
5.2
5.3
-1.5
OCT
5.1
5.3
-4.3
NOV
8.0
6.3
26.4
DEC
5.3
6.4
-17.7
JAN
5.2
6.8
-23.6
ANN
5.8
6.2
-5.6
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6.0 SUMMARY AND DISCUSSION There are a number of factors that might have an influence on the interpretation of the winds observed over this annual study period at the Chehalem Mountains site. First, measurements were taken from only one location and it is possible that other locations in the immediate area might provide better exposure to the prevailing winds. A second factor that is important to consider is that observations were collected at only one height. Flow near the ground can be very complex and difficult to estimate in areas with significant vegetation and terrain variations. These types of flows are influenced by many factors including the density of the air and the exact shape and orientation of the local terrain. Observations taken at a different height above ground would most likely show some differences that might be important to a determination of economic feasibility. A better understanding of the wind shear (variation of wind with height) would also improve the confidence of the power estimates presented here. In summary, 1)
Data quality was good and a sufficient quantity of data was obtained to enable conditions to be characterized for a complete annual analysis period. The annual mean wind speed at the site at the sensor height of 77 ft. is 9.8 mph. The highest monthly mean was 12.4 mph (December 2009).
2)
The strongest and most consistent winds come from the north-northeast and the south. It is expected that during other years the breakdown between these might be different. Each, however, has the potential for energy producing winds.
3)
Comparisons with a nearby site where a longer history of observations are available suggest that during the annual study period (February 2009 to January 2010) the winds were about 5.6% below normal. It is not clear how well this represents the winter conditions at the current site, however.
4)
Gross annual capacity factors computed for the site using various assumptions range between 11% and 16%. Most of this is contributed during winter months.
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Appendix A: Arial view of the location of the Chehalem Mountain site.
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Appendix C: Site Visit Records and wind gust during period prior to visit. Changes Made Date: 01/24/2009 02/01/2009 03/12/2009 05/20/2009 06/15/2009 07/12/2009 09/08/2009 12/10/2010 01/22/2010 03/10/2010
Plug Y Y Y Y Y Y Y Y Y
Battery
?
Time
Gust (mph) 35 54 55 50 34 42 67 67 45
Comment Site Installed *Data sheet not sent *Data sheet not sent * Data sheet incomplete * Data sheet incomplete Battery volt increased from 7.9 to 8.2
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Appendix D: Miscellaneous analysis Tables. STATION – Chehalem Mtns. (Site 0602) WIND SPEED FREQUENCY DISTRIBUTION WITH NORMALIZED AVAILABLE ENERGY DATA PERIOD OF RECORD 2/2009 - 1/2010 NORMALIZATION PERIOD - ONE YEAR AVERAGE WIND SPEED FOR PERIOD: 9.8 MPH NORMALIZED AVAILABLE ENERGY: 918.2 KWH/M**2/YEAR TOTAL HOURS OBSERVED: 8538 NORMALIZED NORMALIZED SPD HOURS/ MPH PERIOD 0 145 1 183 2 347 3 393 4 496 5 527 6 621 7 627 8 588 9 556 10 577 11 523 12 473 13 407 14 376 15 322 16 250 17 220 18 199 19 174 20 145 21 110 22 83 23 60 24 36 25 22 26 26 27 19 28 8 29 14 30 5 31 2 32 0 33 1 34 3
RELFREQ 1.70 2.14 4.06 4.60 5.81 6.17 7.27 7.34 6.89 6.51 6.76 6.13 5.54 4.77 4.40 3.77 2.93 2.58 2.33 2.04 1.70 1.29 0.97 0.70 0.42 0.26 0.30 0.22 0.09 0.16 0.06 0.02 0.00 0.01 0.04
CUMHRS 8538 8393 8210 7863 7470 6974 6447 5826 5199 4611 4055 3478 2955 2482 2075 1699 1377 1127 907 708 534 389 279 196 136 100 78 52 33 25 11 6 4 4 3
CUMRELFREQ 100.00 98.30 96.16 92.09 87.49 81.68 75.51 68.24 60.89 54.01 47.49 40.74 34.61 29.07 24.30 19.90 16.13 13.20 10.62 8.29 6.25 4.56 3.27 2.30 1.59 1.17 0.91 0.61 0.39 0.29 0.13 0.07 0.05 0.05 0.04
AVAIL. ENERGY KWH/M**2/YEAR 0.0 0.0 0.1 0.6 1.7 3.5 7.2 11.6 16.2 21.8 31.1 37.5 44.0 48.1 55.5 58.5 55.1 58.2 62.5 64.2 62.4 54.8 47.6 39.3 26.8 18.5 24.6 20.1 9.5 18.4 7.3 3.2 0.0 1.9 6.3
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DEC 12.4 744 0.0 0 12.4
NOV 11.3 720 0.0 0 11.3
OCT 8.7 744 0.0 0 8.7
SEP 9.8 720 0.0 0 9.8
AUG 8.1 744 0.0 0 8.1
JUL 9.7 744 0.0 0 9.7
JUN 7.7 720 0.0 0 7.7
MAY 10.2 744 0.0 0 10.2
APR 9.1 720 0.0 0 9.1
MAR 9.7 744 0.0 0 9.7
FEB 9.6 672 0.0 0 9.6
0.0 0 11.8 522
11.8
2009 # OBS 2010 # OBS
AVG
1/2010
JAN
MONTHLY WIND SPEEDS (MPH) DATA PERIOD OF RECORD 2/2009 -
STATION – Chehalem Mtns. (Site 0602)
9.80
11.81
522 8538
9.67
AVG
8016
# OBS
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9.8
9.4
9.5
9.3
9.1
9.0
9.0
9.1
9.2
13.2 9.0 10.9 8.0 9.4 6.9 7.7 6.6 8.8 7.4 11.5 12.1 9.3
13.1 9.0 10.7 8.1 9.3 7.5 7.7 7.1 9.0 7.2 11.6 11.9 9.3
9.1
9.1
10.3 10.8 8.7 9.8 12.1 9.6 12.3 10.1 11.3 9.0 11.4 13.5
10.0 10.7 8.8 10.7 12.4 10.2 13.6 10.6 11.4 9.5 11.2 13.3
10.3 11.1 9.0 10.8 12.5 10.0 14.0 10.3 11.0 9.6 11.3 13.5
11.2 10.8 9.1 10.6 11.6 9.8 13.5 10.0 10.8 10.2 11.3 13.1
9.5 10.1 10.7 11.1 11.1 11.0 10.8
12.1 11.3 11.4 11.3 10.4 8.9 8.4 9.1 10.0 10.4 10.3 9.7 9.0 9.0 8.4 8.4 8.7 7.7 7.9 8.7 9.7 9.9 10.2 11.1 11.8 7.8 8.2 7.7 8.0 8.8 7.4 7.5 7.5 8.6 9.8 7.6 7.9 7.8 8.4 9.4 8.9 8.6 8.6 9.0 10.3 7.8 7.5 7.2 7.6 8.3 11.1 10.5 10.7 11.4 11.9 12.2 11.9 12.7 12.8 13.1
10.5 10.2 10.0 10.0
12.8 8.9 10.6 8.2 9.3 6.4 7.3 6.1 9.1 7.4 11.2 12.6
AVG SPD
13.0 8.3 10.1 8.2 9.2 6.0 7.3 6.0 9.3 8.0 11.2 12.4
11.2 10.3 9.1 10.6 11.5 9.2 12.8 10.1 10.6 10.2 11.3 12.7
12.7 8.7 10.3 8.2 8.9 5.6 7.6 5.7 9.0 8.0 11.5 12.4
11.3 10.2 10.5 8.9 8.7 5.7 8.5 6.3 9.6 9.0 11.8 12.3
11.5 9.7 10.7 8.7 8.3 6.0 8.9 6.9 9.9 9.5 11.9 12.1
11.1 9.4 10.9 8.9 8.7 6.2 8.9 7.2 9.5 9.3 11.7 11.9
11.7 9.3 10.6 9.2 9.4 7.0 9.5 7.8 10.3 9.7 11.4 12.0
12.9 9.3 10.1 9.6 9.9 7.3 10.9 8.0 10.3 9.3 11.0 11.7
13.1 8.9 9.2 9.2 10.2 7.7 10.8 8.8 10.2 9.4 11.3 11.8
12.6 9.5 9.2 9.8 10.6 8.0 11.3 9.3 9.9 10.0 11.1 12.2
12.3 9.5 8.7 10.1 11.0 8.7 12.4 9.7 10.3 10.4 11.4 11.9
JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
12.4 9.8 10.0 8.7 8.7 5.5 7.9 6.1 8.9 8.4 11.6 12.3
900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 2200 2300 2400
800
700
600
500
400
300
200
100
1/2010
MON
DIURNAL WIND SPEEDS (MPH) DATA PERIOD OF RECORD 2/2009 -
STATION – Chehalem Mtns. (Site 0602)
9.8
11.8 9.6 9.7 9.1 10.2 7.7 9.7 8.1 9.8 8.7 11.3 12.4
AVG SPD
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NOTE:
N NNE NE ENE E ESE SE SSE S SSW SW WSW W WNW NW NNW CALM TOTAL %
DIR
9.8
100.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
0.0
0.1
0.3
0.7
1.6
4.6
7.2
55.8 17.5 12.3
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.
10.6 12.2 6.7 5.5 3.9 4.4 3.9 4.6 10.1 9.9 7.5 6.7 4.7 4.5 4.8 4.9 21.8 23.7 2.1 1.0 0.9 0.5 0.7 1.4 24.2 12.5 3.5 2.0 1.4 1.0 0.7 0.9 1.7 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 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 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 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 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 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 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 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 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0
0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.1 0.0 0.0 0.0 0.0 0.0 0.0
0.0 0.6 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0
0.1 0.9 0.0 0.0 0.0 0.0 0.0 0.0 0.4 0.2 0.0 0.0 0.0 0.0 0.0 0.0
0.9 2.1 0.0 0.0 0.0 0.0 0.0 0.0 1.1 0.6 0.0 0.0 0.0 0.0 0.0 0.0
2.1 2.6 0.0 0.0 0.0 0.0 0.0 0.0 1.6 0.7 0.1 0.0 0.0 0.0 0.0 0.0
3.6 3.7 0.1 0.0 0.0 0.0 0.0 0.0 3.0 1.5 0.3 0.1 0.0 0.0 0.0 0.0
5.2 4.1 0.2 0.1 0.0 0.0 0.0 0.0 4.7 2.2 0.5 0.2 0.0 0.0 0.0 0.0
9.9 9.7 1.7 0.9 0.9 0.5 0.7 1.4 13.3 7.1 2.5 1.7 1.4 1.0 0.7 0.9
MEAN SPEED (MPH)
TOTAL %
>= 55
52 TO 55
49 TO 52
46 TO 49
43 TO 46
40 TO 43
37 TO 40
34 TO 37
31 TO 34
28 TO 31
25 TO 28
22 TO 25
19 TO 22
16 TO 19
13 TO 16
10 TO 13
0 TO 10
SPEED CATEGORIES(MPH)
WIND ROSE FOR ALL DATA 8538 OBSERVATIONS DATA PERIOD OF RECORD - 2/2009 - 1/2010
STATION – Chehalem Mtns. (Site 0602)
Wind Resource Evaluation: Chehalem Mountains
22
7508
888.5 1.1 0.6 0.7 1.4
5.1
15.8
134.2
247.4
1.9
1.3
1.0
0.9
2.0
6.8
388.2
80.2
NOTE:
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.
TOT
506 641 701 632 595 564 562 606 627 680 693 701 117.6 66.7 85.8 55.2 58.5 30.3 45.9 30.4 64.7 60.5 111.9 161.0 0.0 0.0 0.1 0.1 0.1 0.1 0.0 0.1 0.1 0.3 0.0 0.0 0.0 0.0 0.2 0.0 0.0 0.1 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.1 0.1 0.1 0.0 0.0 0.0 0.1 0.2 0.0 0.0
0.0 0.0 0.4 0.2 0.2 0.1 0.1 0.0 0.1 0.2 0.0 0.0
0.0 0.0 1.3 0.9 0.8 1.1 0.1 0.3 0.3 0.1 0.2 0.0
0.0 0.2 4.5 1.5 3.7 1.8 0.6 0.4 1.1 0.6 1.4 0.1
16.7 11.4 20.8 11.6 21.6 4.5 4.1 2.4 6.4 6.0 26.0 2.7
56.6 9.9 25.2 15.9 10.2 2.1 3.1 1.5 6.6 21.3 69.2 25.9
0.8 0.2 0.0 0.0 0.3 0.1 0.0 0.0 0.0 0.3 0.1 0.1
JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
1.1 0.1 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0
OBS.
0.5 0.0 0.1 0.0 0.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0
TOTAL
0.3 0.1 0.0 0.0 0.2 0.0 0.0 0.0 0.0 0.1 0.0 0.1
NNW
0.7 0.5 0.0 0.0 0.3 0.0 0.0 0.0 0.0 0.2 0.0 0.2
NW
1.9 1.4 0.1 0.9 1.1 0.0 0.0 0.0 0.1 0.5 0.2 0.5
WNW
36.9 40.9 31.6 16.7 10.4 9.0 19.2 11.8 40.6 27.7 13.5 130.0
W
2.1 2.0 1.4 7.3 8.9 11.3 18.6 13.7 9.3 3.0 1.2 1.3
WSW
SW
SSW
S
SSE
SE
ESE
E
ENE
NE
N
MON
NNE
ENERGY ROSE (TOTALS ARE NORMALIZED AVAILABLE ENERGY (KWH/M**2) DATA PERIOD OF RECORD 2/2009 - 1/2010
STATION – Chehalem Mtns. (Site 0602)
8760
744 672 744 720 744 720 744 744 720 744 720 744
NORM.
Wind Resource Evaluation: Chehalem Mountains
Prepared By:
Energy Resources Research laboratory Oregon State University
May 20, 2010
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: Chehalem Mountains
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OREGON ANEMOMETER LOAN PROGRAM
Wind Resource Evaluation: Chehalem Mountains
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: Chehalem Mountains
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Wind Resource Evaluation: Chehalem Mountains
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1.0
INTRODUCTION
The Oregon anemometer loan program was established in the fall of 2002 in order to assist landowners in the state evaluate the wind energy potential of their property. The program is funded by a grant from the Energy Trust of Oregon and is administered by the Energy Resources Research Laboratory at Oregon State University. The program involves several steps, beginning with a preliminary evaluation of the site. If estimates of the site show promise then a monitoring system is installed for a fixed duration (typically one year). The site is monitored regularly and the data processed and checked at regular intervals. Upon completion of the first year, the collected wind data is summarized and a report is prepared evaluating the wind data and the wind resource of the location. This report represents the final portion of the project and is designed to give the landowner the information necessary to make an informed choice about the role wind energy might play in their property. The report is separated in to sections with section 2.0 devoted to a description of the site, its location and the type of terrain found there. Section 3.0 includes a summary of the wind data collected during the study period including data quality checks and a characterization of the measured winds. In section 4.0 the wind data is analyzed to determine the amount of power production that might be expected from the site and to examine characteristics that might influence these estimates. This is followed in section 5.0 in which wind data from a nearby site is summarized and used to place the current study period in climatological context. A discussion and summary is then presented in section 6.0
Wind Resource Evaluation: Chehalem Mountains
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2.0
SITE DESCRIPTION Site Name: Latitude: Longitude: Elevation: Tower Height: Site #
Chehalem Mountains 45.354 (WGS 84) 124.989 1437 ft. 77 feet (Est.) 0602
Types of Sensors:
NRG Maximum #40 wind speed NRG 200 series 2 wind vane Single level mounted on an existing tower
Instrumentation: County: Installation Date: Data Available to:
Yamhill January 24, 2009 March 10, 2010 (Monitoring will continue until sensors are removed)
Site Location: This site is located on private property in an area known as the Chehalem Mountains. The Chehalem Mountains are a sharp, relatively long ridge line that is oriented Northwest to Southeast and is located just north of the City of Newberg in Western Oregon. The site is positioned near the highest portion of the ridge, The area consists of rural homes with isolated groves of tall trees. Project Description: The landowner is in the process of developing a small wind turbine and an anemometer was loaned to help evaluate a test unit at the site. The anemometer was installed by the landowner. Direction orientation and placement has not been verified by the ERRL. No power production data was provided for comparison. Data Collection and Processing: NRG equipment was used at this site including #40 anemometers and a Wind Explorer data logger. Data plugs were swapped out on roughly a monthly basis by the landowner. Raw NRG files were read and downloaded from the data cards and used to generate 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. Data were plotted and scanned manually to detect problems and to flag periods of suspected icing. No problems with the site have been identified that might affect the interpretation of the collected wind data.
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3.0
WIND CHARACTERISTICS
In the following sections, several characteristics of the winds at the Chehalem Mountains 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 characteristics 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. These evaluations are confined to a single annual period so that the results are not biased by the addition of data from only a particular season or a portion of a year. The period analyzed here is for February 1, 2009 to January 31, 2010.
Table 3.1: Monthly mean wind speed values and data recovery for the Chehalem Mountains site.
Month FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC JAN ANN
Site 0602 - 77' (mph) Rec. (%) 9.6 100.0 9.7 100.0 9.1 100.0 10.2 100.0 7.7 100.0 9.7 100.0 8.1 100.0 9.8 100.0 8.7 100.0 11.3 100.0 12.4 100.0 11.8 70.2 9.8
Wind Resource Evaluation: Chehalem Mountains
97.5
3
Diurnal Means: The diurnal pattern of winds is an important characteristic for many wind sites and helps illuminate the mechanisms responsible for the winds. In general, a diurnal pattern is associated with a site at which strong thermal influences play a role. These are normally accentuated during the summer months when the daily heating cycle is at its greatest. Diurnal variations can also provide an indication of dependable and predictable winds at a site. For this site there is a much better defined diurnal pattern in the July data that begins to rise in the evening and peaks around 10:00 at night.
Diurnal Wind Speed - 77' 16
Wind Speed (mph)
14 12 10 8
January
6
July
4
Annual
2 0 0
400
800
1200
1600
2000
2400
Hour of Day
Figure 3.1: Diurnal mean wind speed values for the Chehalem Mountains site.
Frequency Distribution: How the wind speed at a site is distributed over various wind speed categories is an important indication of the wind resource potential of a site. An ideal site would have winds that blow at a high rate for long periods. This is not normally the case, however, and wind records from a site show a skewed distribution with a higher frequency of winds at lower speeds.
Wind Resource Evaluation: Chehalem Mountains
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Speed Frequency Dist. - 77' 8 7
Frequency (%)
6 5 4
3 2 1 0 0
5
10
15
20
25
30
35
40
Wind Speed Category (mph)
Figure 3.2: Wind speed frequency distribution for the Chehalem Mountains site.
Wind Rose: How the wind varies with direction is also important to understanding the physical processes that contribute to the local winds at a site and eventually in designing a wind facility. A wind rose is often used to display this information and show the frequency with which the wind occurs in different direction categories. A wind rose plot can also be used to show the strength of the wind from each of the direction categories. This is done here using color segments. Winds for the annual period as a whole are shown in Figure 3.3 and indicate the winds come from two general directions; the northnortheast (and north) and the south (and south-southwest). The strength of each of these are comparable.
Wind Resource Evaluation: Chehalem Mountains
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Figure 3.3: Wind rose for each of 16 wind direction categories for the annual analysis period.
In order understand better the winds at the site during different times of year; similar plots have been constructed using data from the individual months for the winter and summer. These can be seen in figures 3.4a-b and show any differences between the two periods. The winds during July and likely during the other summer months, the winds come generally from the north. The direction of the winds in March is reversed and shows strong winds from the south. March was likely a period when Pacific storms were passing through the region.
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Figure 3.4a-b: Wind rose for each of 16 wind direction categories for a winter and summer month at the Chehalem Mountain site.
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Energy Rose: In the same way a wind rose shows the strength and frequency of the wind for different direction categories, an energy rose can show the relative energy that can be expected for these same direction categories. From the wind rose it was apparent that the strongest and most frequent winds were coming from the north-northeast and south. By looking at the energy rose (Figure 3.5) it is clear that these account for nearly all of the energy producing winds at the site. As small percentage do come from other directions but the contribution is minimal. Further, from Figure 3.6 it’s clear that the bulk of the energy producing winds can be expected to occur during the winter months but that some can be expected during other months as well.
Energy Rose - Chehalem 77' Normalized Available Energy (% of Annual)
50 45 40 35 30 25 20 15
10 5 0 N
NNE
NE
ENE
E
ESE
SE
SSE
S
SSW
SW WSW
W WNW NW NNW
Figure 3.5: Percentage (%) of expected total normalized energy for each of 16 wind direction categories for the annual analysis period.
Wind Resource Evaluation: Chehalem Mountains
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Chehalem 77' - Percent of Annual Normalized Available Energy (% of Annual)
20 18 16 14 12 10 8 6
4 2 0 FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
JAN
Figure 3.6: Frequency (%) of expected energy for each month of the annual analysis period.
Wind Resource Evaluation: Chehalem Mountains
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4.0
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 mean and standard deviation of the hourly values, the recovery rate, the maximum one hour average, the wind power density and the frequency that the wind was observed within a wind speed range (12 mph to 60 mph). These quantities are shown in Table 4.1. Table 4.1: Observed and computed power quantities at the Chehalem Mountains site. Site 0602 - 77' Shear Factor Month FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC JAN ANN
(mph) 9.6 9.7 9.1 10.2 7.7 9.7 8.1 9.8 8.7 11.3 12.4 11.8
Rec. (%) 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 70.2
0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1
9.8
97.5
0.1
Time in Range (12- Available Max 1-Hr 60) Energy (mph) mph (%) kWh/m**2 26.0 32.7 64 28.7 30.2 82 23.6 25.1 58 24.5 34.9 71 23.6 20.8 42 23.1 31.2 65 20.6 18.4 41 24.6 29.3 67 24.6 25.4 59 33.5 39.6 111 30.4 47.7 151 34.2 47.1 116 34.2
31.5
916
The values in Table 4.1 reveal a number of things about the potential for generating energy at the Chehalem Mountains site. First, it is clear that there is some potential for generation during each month but the potential is lower during the summer months. The lowest month was August when the winds blew in a typical operating range less than 20% of the time. The highest was during December 2009 and January 2010. These months were a little abnormal for this period as the Northwest was under the influence of an El Nino pattern that directed much of the storm activity to the south. The result appeared to be strong north-northeast winds at this site. In addition to evaluating these basic power characteristics it is possible to estimate how specific wind turbines might interact with the winds at a particular site. Using the collected wind data and the characteristics of a particular wind turbine it is possible to
Wind Resource Evaluation: Chehalem Mountains
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estimate the amount of power it could produce. This is done by comparing the wind data with a power curve for a specific wind turbine. A power curve is simply the curve that shows the relationship between the wind speed and the amount of power a turbine can produce. An example is provided in Figure 4.1. There are several portions of the curve that are important. At low wind speeds, below the cut-in speed, no energy is produced. Any turbine has a lower threshold below which it won’t operate. This is in part because there is little energy available at these levels. In the middle is a ramp up zone where even a small increase in wind speed results in a larger increase in power. At some point, depending on the type of turbine, the amount of power that is generated reaches the rated limit of the generator (rated capacity). The blades are then pitched to spill energy and protect the generator. At the upper end, energy production will stop if the winds reach a cut-out speed. This is the speed at which a turbine is shut down to protect the structural integrity of the turbine. In Table 4.2, energy capacity factors are shown for five different types of turbines. The capacity factor is the ratio of the amount of energy produce to the amount of energy that could be produced if a turbine ran at its rated capacity all the time. The rated capacity is effectively a theoretical maximum and capacity factors generally range from 0.0 to 0.40. It’s difficult to compare these because of the different turbine characteristics but they are given to provide a range of values that might be expected from this site. In computing these values, it is necessary to adjust the observed data which are measured at 77 feet to the hub height of the particular turbine. In this case this is done using a standard assumption that the wind follows a typical power law profile. To do this a shear coefficient must be used. A value of 0.100 is used here. These particular turbines are likely larger than would be used at this site but should still provide an indication of the resource for the site.
Wind Resource Evaluation: Chehalem Mountains
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120
Power Output (% of Rated)
100
80
60
40
20
0 0
10
20
30
40
50
Wind Speed (mph)
Figure 4.2: Sample power curve for a theoretical turbine The capacity factors in Table 4.2 support the indications provided by the wind data statistics. The capacity factors for August are the lowest (0.078) and are highest for December (0.239) and January (0.195). The overall gross capacity factors range from 0.112 to 0.159. While these are relatively low for any commercial site they do suggest a limited potential at the location.
Wind Resource Evaluation: Chehalem Mountains
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Table 4.2: Gross capacity factors computed for various wind turbines using the Chehalem Mountains site and a shear coefficient of 0.100. Site 0602 - 77' Month FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC JAN ANN
GE 70.5
Nordex 80 Souzlon 88
Vestas
Northwind
PS600
100
(mph) 9.6 9.7 9.1 10.2 7.7 9.7 8.1 9.8 8.7 11.3 12.4 11.8
Rec. (%) 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 70.2
1500 kW 0.127 0.139 0.107 0.128 0.074 0.116 0.069 0.122 0.104 0.189 0.252 0.196
2500 kW 0.106 0.117 0.088 0.106 0.061 0.096 0.057 0.101 0.087 0.160 0.215 0.165
2000 kW 0.153 0.162 0.129 0.157 0.090 0.141 0.085 0.145 0.125 0.219 0.288 0.230
600 kW 0.121 0.134 0.102 0.123 0.071 0.112 0.067 0.116 0.100 0.178 0.236 0.186
100 kW 0.131 0.095 0.112 0.137 0.082 0.124 0.078 0.125 0.107 0.182 0.239 0.195
9.8
97.5
0.134
0.112
0.159
0.127
0.136
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5.0 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 following table shows monthly mean wind speeds, long-term normals and wind speed departures at the Salem Airport. This is a National Weather Service site and has been in place for a number of years. This comparison suggests the winds during this monitoring period overall (February 2009 - January 2010) were slightly below normal (5.6%). During several months there were significant departures including December 2009 when the winds were 17.7% below normal and January 2010 when the winds were 23.6 % below normal. There are significant due to the higher wind potential during these months. Although the winds were lower at the airport is expected that these conditions may have actually resulted in higher winds in the Chehalem Mountains due to the elevation difference. This winter period was somewhat different than usual and is attributed to the presence of an El Nino in the Pacific. Although the area has received normal rainfall amounts there have been fewer strong storms affecting the region. Conditions were also mild and may have resulted in fewer southerly wind storms in the area. However, this was not tested explicitly. The lower than normal winds observed at the Salem Airport for August do show that the weaker winds observed at the Chehalem mountains tower might have been somewhat anomalous and somewhat higher winds might be expected during these months for other periods. Table 5.1: Monthly means for the current observation period, long-term normals and departures for the current annual period. Salem McNary Field - NWS Current 2000-2009 Departure Month (mph) (mph) (% ) FEB
4.4
5.8
-24.4
MAR
7.9
7.1
10.9
APR
6.0
6.5
-8.0
MAY
6.3
6.0
5.6
JUN
5.8
6.3
-7.8
JUL
5.5
6.3
-12.5
AUG
5.1
5.8
-12.8
SEP
5.2
5.3
-1.5
OCT
5.1
5.3
-4.3
NOV
8.0
6.3
26.4
DEC
5.3
6.4
-17.7
JAN
5.2
6.8
-23.6
ANN
5.8
6.2
-5.6
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6.0 SUMMARY AND DISCUSSION There are a number of factors that might have an influence on the interpretation of the winds observed over this annual study period at the Chehalem Mountains site. First, measurements were taken from only one location and it is possible that other locations in the immediate area might provide better exposure to the prevailing winds. A second factor that is important to consider is that observations were collected at only one height. Flow near the ground can be very complex and difficult to estimate in areas with significant vegetation and terrain variations. These types of flows are influenced by many factors including the density of the air and the exact shape and orientation of the local terrain. Observations taken at a different height above ground would most likely show some differences that might be important to a determination of economic feasibility. A better understanding of the wind shear (variation of wind with height) would also improve the confidence of the power estimates presented here. In summary, 1)
Data quality was good and a sufficient quantity of data was obtained to enable conditions to be characterized for a complete annual analysis period. The annual mean wind speed at the site at the sensor height of 77 ft. is 9.8 mph. The highest monthly mean was 12.4 mph (December 2009).
2)
The strongest and most consistent winds come from the north-northeast and the south. It is expected that during other years the breakdown between these might be different. Each, however, has the potential for energy producing winds.
3)
Comparisons with a nearby site where a longer history of observations are available suggest that during the annual study period (February 2009 to January 2010) the winds were about 5.6% below normal. It is not clear how well this represents the winter conditions at the current site, however.
4)
Gross annual capacity factors computed for the site using various assumptions range between 11% and 16%. Most of this is contributed during winter months.
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Appendix A: Arial view of the location of the Chehalem Mountain site.
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Appendix C: Site Visit Records and wind gust during period prior to visit. Changes Made Date: 01/24/2009 02/01/2009 03/12/2009 05/20/2009 06/15/2009 07/12/2009 09/08/2009 12/10/2010 01/22/2010 03/10/2010
Plug Y Y Y Y Y Y Y Y Y
Battery
?
Time
Gust (mph) 35 54 55 50 34 42 67 67 45
Comment Site Installed *Data sheet not sent *Data sheet not sent * Data sheet incomplete * Data sheet incomplete Battery volt increased from 7.9 to 8.2
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Appendix D: Miscellaneous analysis Tables. STATION – Chehalem Mtns. (Site 0602) WIND SPEED FREQUENCY DISTRIBUTION WITH NORMALIZED AVAILABLE ENERGY DATA PERIOD OF RECORD 2/2009 - 1/2010 NORMALIZATION PERIOD - ONE YEAR AVERAGE WIND SPEED FOR PERIOD: 9.8 MPH NORMALIZED AVAILABLE ENERGY: 918.2 KWH/M**2/YEAR TOTAL HOURS OBSERVED: 8538 NORMALIZED NORMALIZED SPD HOURS/ MPH PERIOD 0 145 1 183 2 347 3 393 4 496 5 527 6 621 7 627 8 588 9 556 10 577 11 523 12 473 13 407 14 376 15 322 16 250 17 220 18 199 19 174 20 145 21 110 22 83 23 60 24 36 25 22 26 26 27 19 28 8 29 14 30 5 31 2 32 0 33 1 34 3
RELFREQ 1.70 2.14 4.06 4.60 5.81 6.17 7.27 7.34 6.89 6.51 6.76 6.13 5.54 4.77 4.40 3.77 2.93 2.58 2.33 2.04 1.70 1.29 0.97 0.70 0.42 0.26 0.30 0.22 0.09 0.16 0.06 0.02 0.00 0.01 0.04
CUMHRS 8538 8393 8210 7863 7470 6974 6447 5826 5199 4611 4055 3478 2955 2482 2075 1699 1377 1127 907 708 534 389 279 196 136 100 78 52 33 25 11 6 4 4 3
CUMRELFREQ 100.00 98.30 96.16 92.09 87.49 81.68 75.51 68.24 60.89 54.01 47.49 40.74 34.61 29.07 24.30 19.90 16.13 13.20 10.62 8.29 6.25 4.56 3.27 2.30 1.59 1.17 0.91 0.61 0.39 0.29 0.13 0.07 0.05 0.05 0.04
AVAIL. ENERGY KWH/M**2/YEAR 0.0 0.0 0.1 0.6 1.7 3.5 7.2 11.6 16.2 21.8 31.1 37.5 44.0 48.1 55.5 58.5 55.1 58.2 62.5 64.2 62.4 54.8 47.6 39.3 26.8 18.5 24.6 20.1 9.5 18.4 7.3 3.2 0.0 1.9 6.3
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Wind Resource Evaluation: Chehalem Mountains
19
DEC 12.4 744 0.0 0 12.4
NOV 11.3 720 0.0 0 11.3
OCT 8.7 744 0.0 0 8.7
SEP 9.8 720 0.0 0 9.8
AUG 8.1 744 0.0 0 8.1
JUL 9.7 744 0.0 0 9.7
JUN 7.7 720 0.0 0 7.7
MAY 10.2 744 0.0 0 10.2
APR 9.1 720 0.0 0 9.1
MAR 9.7 744 0.0 0 9.7
FEB 9.6 672 0.0 0 9.6
0.0 0 11.8 522
11.8
2009 # OBS 2010 # OBS
AVG
1/2010
JAN
MONTHLY WIND SPEEDS (MPH) DATA PERIOD OF RECORD 2/2009 -
STATION – Chehalem Mtns. (Site 0602)
9.80
11.81
522 8538
9.67
AVG
8016
# OBS
Wind Resource Evaluation: Chehalem Mountains
20
9.8
9.4
9.5
9.3
9.1
9.0
9.0
9.1
9.2
13.2 9.0 10.9 8.0 9.4 6.9 7.7 6.6 8.8 7.4 11.5 12.1 9.3
13.1 9.0 10.7 8.1 9.3 7.5 7.7 7.1 9.0 7.2 11.6 11.9 9.3
9.1
9.1
10.3 10.8 8.7 9.8 12.1 9.6 12.3 10.1 11.3 9.0 11.4 13.5
10.0 10.7 8.8 10.7 12.4 10.2 13.6 10.6 11.4 9.5 11.2 13.3
10.3 11.1 9.0 10.8 12.5 10.0 14.0 10.3 11.0 9.6 11.3 13.5
11.2 10.8 9.1 10.6 11.6 9.8 13.5 10.0 10.8 10.2 11.3 13.1
9.5 10.1 10.7 11.1 11.1 11.0 10.8
12.1 11.3 11.4 11.3 10.4 8.9 8.4 9.1 10.0 10.4 10.3 9.7 9.0 9.0 8.4 8.4 8.7 7.7 7.9 8.7 9.7 9.9 10.2 11.1 11.8 7.8 8.2 7.7 8.0 8.8 7.4 7.5 7.5 8.6 9.8 7.6 7.9 7.8 8.4 9.4 8.9 8.6 8.6 9.0 10.3 7.8 7.5 7.2 7.6 8.3 11.1 10.5 10.7 11.4 11.9 12.2 11.9 12.7 12.8 13.1
10.5 10.2 10.0 10.0
12.8 8.9 10.6 8.2 9.3 6.4 7.3 6.1 9.1 7.4 11.2 12.6
AVG SPD
13.0 8.3 10.1 8.2 9.2 6.0 7.3 6.0 9.3 8.0 11.2 12.4
11.2 10.3 9.1 10.6 11.5 9.2 12.8 10.1 10.6 10.2 11.3 12.7
12.7 8.7 10.3 8.2 8.9 5.6 7.6 5.7 9.0 8.0 11.5 12.4
11.3 10.2 10.5 8.9 8.7 5.7 8.5 6.3 9.6 9.0 11.8 12.3
11.5 9.7 10.7 8.7 8.3 6.0 8.9 6.9 9.9 9.5 11.9 12.1
11.1 9.4 10.9 8.9 8.7 6.2 8.9 7.2 9.5 9.3 11.7 11.9
11.7 9.3 10.6 9.2 9.4 7.0 9.5 7.8 10.3 9.7 11.4 12.0
12.9 9.3 10.1 9.6 9.9 7.3 10.9 8.0 10.3 9.3 11.0 11.7
13.1 8.9 9.2 9.2 10.2 7.7 10.8 8.8 10.2 9.4 11.3 11.8
12.6 9.5 9.2 9.8 10.6 8.0 11.3 9.3 9.9 10.0 11.1 12.2
12.3 9.5 8.7 10.1 11.0 8.7 12.4 9.7 10.3 10.4 11.4 11.9
JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
12.4 9.8 10.0 8.7 8.7 5.5 7.9 6.1 8.9 8.4 11.6 12.3
900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 2200 2300 2400
800
700
600
500
400
300
200
100
1/2010
MON
DIURNAL WIND SPEEDS (MPH) DATA PERIOD OF RECORD 2/2009 -
STATION – Chehalem Mtns. (Site 0602)
9.8
11.8 9.6 9.7 9.1 10.2 7.7 9.7 8.1 9.8 8.7 11.3 12.4
AVG SPD
Wind Resource Evaluation: Chehalem Mountains
21
NOTE:
N NNE NE ENE E ESE SE SSE S SSW SW WSW W WNW NW NNW CALM TOTAL %
DIR
9.8
100.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
0.0
0.1
0.3
0.7
1.6
4.6
7.2
55.8 17.5 12.3
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.
10.6 12.2 6.7 5.5 3.9 4.4 3.9 4.6 10.1 9.9 7.5 6.7 4.7 4.5 4.8 4.9 21.8 23.7 2.1 1.0 0.9 0.5 0.7 1.4 24.2 12.5 3.5 2.0 1.4 1.0 0.7 0.9 1.7 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 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 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 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 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 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 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 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 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0
0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.1 0.0 0.0 0.0 0.0 0.0 0.0
0.0 0.6 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0
0.1 0.9 0.0 0.0 0.0 0.0 0.0 0.0 0.4 0.2 0.0 0.0 0.0 0.0 0.0 0.0
0.9 2.1 0.0 0.0 0.0 0.0 0.0 0.0 1.1 0.6 0.0 0.0 0.0 0.0 0.0 0.0
2.1 2.6 0.0 0.0 0.0 0.0 0.0 0.0 1.6 0.7 0.1 0.0 0.0 0.0 0.0 0.0
3.6 3.7 0.1 0.0 0.0 0.0 0.0 0.0 3.0 1.5 0.3 0.1 0.0 0.0 0.0 0.0
5.2 4.1 0.2 0.1 0.0 0.0 0.0 0.0 4.7 2.2 0.5 0.2 0.0 0.0 0.0 0.0
9.9 9.7 1.7 0.9 0.9 0.5 0.7 1.4 13.3 7.1 2.5 1.7 1.4 1.0 0.7 0.9
MEAN SPEED (MPH)
TOTAL %
>= 55
52 TO 55
49 TO 52
46 TO 49
43 TO 46
40 TO 43
37 TO 40
34 TO 37
31 TO 34
28 TO 31
25 TO 28
22 TO 25
19 TO 22
16 TO 19
13 TO 16
10 TO 13
0 TO 10
SPEED CATEGORIES(MPH)
WIND ROSE FOR ALL DATA 8538 OBSERVATIONS DATA PERIOD OF RECORD - 2/2009 - 1/2010
STATION – Chehalem Mtns. (Site 0602)
Wind Resource Evaluation: Chehalem Mountains
22
7508
888.5 1.1 0.6 0.7 1.4
5.1
15.8
134.2
247.4
1.9
1.3
1.0
0.9
2.0
6.8
388.2
80.2
NOTE:
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.
TOT
506 641 701 632 595 564 562 606 627 680 693 701 117.6 66.7 85.8 55.2 58.5 30.3 45.9 30.4 64.7 60.5 111.9 161.0 0.0 0.0 0.1 0.1 0.1 0.1 0.0 0.1 0.1 0.3 0.0 0.0 0.0 0.0 0.2 0.0 0.0 0.1 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.1 0.1 0.1 0.0 0.0 0.0 0.1 0.2 0.0 0.0
0.0 0.0 0.4 0.2 0.2 0.1 0.1 0.0 0.1 0.2 0.0 0.0
0.0 0.0 1.3 0.9 0.8 1.1 0.1 0.3 0.3 0.1 0.2 0.0
0.0 0.2 4.5 1.5 3.7 1.8 0.6 0.4 1.1 0.6 1.4 0.1
16.7 11.4 20.8 11.6 21.6 4.5 4.1 2.4 6.4 6.0 26.0 2.7
56.6 9.9 25.2 15.9 10.2 2.1 3.1 1.5 6.6 21.3 69.2 25.9
0.8 0.2 0.0 0.0 0.3 0.1 0.0 0.0 0.0 0.3 0.1 0.1
JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
1.1 0.1 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0
OBS.
0.5 0.0 0.1 0.0 0.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0
TOTAL
0.3 0.1 0.0 0.0 0.2 0.0 0.0 0.0 0.0 0.1 0.0 0.1
NNW
0.7 0.5 0.0 0.0 0.3 0.0 0.0 0.0 0.0 0.2 0.0 0.2
NW
1.9 1.4 0.1 0.9 1.1 0.0 0.0 0.0 0.1 0.5 0.2 0.5
WNW
36.9 40.9 31.6 16.7 10.4 9.0 19.2 11.8 40.6 27.7 13.5 130.0
W
2.1 2.0 1.4 7.3 8.9 11.3 18.6 13.7 9.3 3.0 1.2 1.3
WSW
SW
SSW
S
SSE
SE
ESE
E
ENE
NE
N
MON
NNE
ENERGY ROSE (TOTALS ARE NORMALIZED AVAILABLE ENERGY (KWH/M**2) DATA PERIOD OF RECORD 2/2009 - 1/2010
STATION – Chehalem Mtns. (Site 0602)
8760
744 672 744 720 744 720 744 744 720 744 720 744
NORM.
