Technical Report

NREL/TP-500-46151

December 2009

Wind Turbine Generator System 

Power Performance Test Report 

for the Gaia-Wind 11-kW Wind 

Turbine

A. Huskey, A. Bowen, and D. Jager
Wind Turbine Generator System

Power Performance Test Report

for the

Gaia-Wind 11-kW Wind Turbine

Conducted for

National Renewable Energy Laboratory

1617 Cole Blvd.

Golden, CO 80401

Conducted by

National Wind Technology Center

National Renewable Energy Laboratory

1617 Cole Blvd.

Golden, CO 80401

Arlinda Huskey, Amy Bowen, and Dave Jager

June 11, 2009
ii

Notice

This report was prepared by the National Renewable Energy Laboratory (NREL), operated for 

the United States Department of Energy (DOE) by the Alliance for Sustainable Energy, LLC 

(Alliance), as an account of work sponsored by the United States government. The test results 

documented in this report define the characteristics of the test article as configured and under 

the conditions tested.

THIS REPORT IS PROVIDED "AS IS" AND NEITHER THE GOVERNMENT, ALLIANCE, NREL 

NOR ANY OF THEIR EMPLOYEES, MAKES ANY WARRANTY, EXPRESS OR IMPLIED, 

INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 

PURPOSE, OR ASSUMES ANY LEGAL LIABILITY OR RESPONSIBILITY FOR THE 

ACCURACY, COMPLETENESS, OR USEFULNESS OF ANY SUCH INFORMATION DISCLOSED 

IN THE REPORT, OR OF ANY APPARATUS, PRODUCT, OR PROCESS DISCLOSED, OR 

REPRESENTS THAT ITS USE WOULD NOT INFRINGE PRIVATELY OWNED RIGHTS. 

Neither Alliance nor the U. S. Government shall be liable for special, consequential or incidental 

damages. Reference herein to any specific commercial product, process, or service by trade 

name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its 

endorsement, recommendation, or favoring by the United States government or any agency 

thereof. The views and opinions of the authors expressed herein do not necessarily state or 

reflect those of the United States government or any agency thereof or Alliance. 

NREL is a DOE Laboratory, and as an adjunct of the United States government, cannot certify 

wind turbines. The information in this report is limited to NREL’s knowledge and understanding 

as of this date. 

NREL is accredited by the American Association for Laboratory Accreditation (A2LA) and the 

results shown in this test report have been determined in accordance with the NREL’s terms of 

accreditation unless stated otherwise in the report.

This report shall not be reproduced, except in full, without the written approval of Alliance or 

successor operator of NREL.

Approval By: __________________________________________________________

Arlinda Huskey, NREL Test Engineer Date

Review By: ___________________________________________________________

Jeroen van Dam, NREL Test Engineer Date
iii

Contents

List of Tables......................................................................................................................................................iv

List of Figures.....................................................................................................................................................iv

1. Background ............................................................................................................................................... 1

2. Test Summary............................................................................................................................................ 1

3. Test Turbine Configuration......................................................................................................................... 4

4. Test Site Description .................................................................................................................................. 5

5. Description of Test Equipment................................................................................................................... 7

6. Description of Test Procedure .................................................................................................................... 9

7. Test Results ..............................................................................................................................................10

7.1. Tabular Results of Power Performance Test ..............................................................................................10

7.2. Graphical Results Power Performance Test ...............................................................................................14

8. Deviations and Exceptions ........................................................................................................................21

8.1. Deviations from the Standard ....................................................................................................................21

8.2. Exceptions to NWTC-CT Quality Assurance System....................................................................................21

A. Appendix - Photographs of the Test Site from the Turbine Base.................................................................22

B. Appendix - Equipment Calibration Sheets..................................................................................................28
iv 

List of Tables 

Table 1. Test turbine configuration ............................................................................................... 4

Table 2. Structures close to test turbine ....................................................................................... 6

Table 3. Criteria for test site without site calibration ..................................................................... 6

Table 4. Equipment used in the power performance test ............................................................. 7

Table 5. Uncertainty values used in the analysis .......................................................................... 9

Table 6. Performance at sea-level air density, 1.225 kg/m3

........................................................ 11

Table 7. Performance at site average density, 0.95 kg/m3

 ......................................................... 12

Table 8. Annual energy production at sea-level density, 1.225 kg/m3

 ........................................ 13

Table 9. Annual energy production at site average density, 0.95 kg/m3

 ..................................... 13

List of Figures 

Figure 1. Power curve summary ................................................................................................... 2

Figure 2. Gaia-Wind 11-kW test turbine at the NWTC .................................................................. 3

Figure 3. Map of the test site ........................................................................................................ 5

Figure 4. Meteorological tower and instruments ........................................................................... 8

Figure 5. Power curve at sea-level density, 1.225 kg/m3

 ............................................................ 14

Figure 6. Power curve at site average density, 0.95 kg/m3

 ......................................................... 15

Figure 7. Scatter plot of mean, standard deviation, minimum, and maximum power data ......... 16

Figure 8. Coefficient of power at sea-level density, 1.225 kg/m3

 ................................................ 17

Figure 9. Wind turbulence intensity as a function of wind speed ................................................ 18

Figure 10. Wind speed and turbulence intensity as a function of wind direction......................... 19

Figure 11. Rotor speed as a function of wind speed (1-minute averages) and binned values ... 20
1

1. Background

This test is being conducted as part of the U.S. Department of Energy’s (DOE) Independent 

Testing project. This project was established to help reduce the barriers of wind energy 

expansion by providing independent testing results for small turbines. In total, four turbines are 

being tested at the National Wind Technology Center (NWTC) as a part of this project. Power 

performance testing is one of up to 5 tests that may be performed on the turbines, including 

duration, safety and function, noise, and power quality tests. 

2. Test Summary

Figure 1 is a summary of the results of a power performance test that the National Renewable 

Energy Laboratory (NREL) conducted on the Gaia-Wind 11-kW small wind turbine (shown in 

Figure 2). In this test, the Gaia-Wind 11-kW turbine was installed at the NWTC near Boulder, 

Colorado. This test was conducted in accordance with the International Electrotechnical 

Commission (IEC) standard, Wind Turbine Generator Systems Part 12: Power Performance 

Measurements of Electricity Producing Wind Turbines, IEC 61400-12-1 Ed.1.0, 2005-12. 

Because the Gaia-Wind 11-kW is a small turbine according to the IEC definition, NREL also 

followed Annex H, which applies to small wind turbines. This test report refers to these 

procedures as the “Standard.” 

In these summary results, power is normalized to sea-level air density. This test began on June 

9, 2008, and ended on October 27, 2008. In all, NREL collected 1070.03 hours of valid data 

during that period. The highest bin filled was the 20.0 m/s bin. The amount of test data is 

sufficient to meet the requirements of the Standard. 
2 

Figure 1. Power curve summary
3

Figure 2. Gaia-Wind 11-kW test turbine at the NWTC
4

3. Test Turbine Configuration

Table 1 lists the configuration of the Gaia-Wind 11-kW that was tested at the NWTC.

Table 1. Test turbine configuration

Turbine make, model, serial number, production 

year

Gaia-Wind 11-kW, 10711114, 2007

Rotor diameter (m) 13

Hub height (m) 18.2

Tower type Tubular

Rated electrical power (kW) 11

Rated wind speed (m/s) 9.5

Rotor speed range (rpm) 56–62

Fixed or variable pitch Fixed blade, variable tip

Number of blades 2

Blade tip pitch angle (deg) 90

Blade make, type, serial number Gaia-Wind T202, glass fiber, centrifugally 

activated tip brake, 2007/22

Control system (device and software version) Gaia-Wind IC-1000, Rev.1:P00515\031020

Measurements verified the rotor diameter. The tip pitch changed when deployed.
5

4. Test Site Description

The test turbine is located at site 3.3B at the NWTC, which is 8 miles south of Boulder, 

Colorado. The terrain consists of mostly flat terrain with short vegetation (see Appendix A for 

photos of the test site). The site has prevailing winds bearing 292 degrees relative to true north. 

For measurements for which it is important to accurately measure wind speed, NREL uses data 

obtained when the wind direction is between 257 and 332, and between 147 and 197 degrees 

true. In this measurement sector, the influence of terrain and obstructions on the anemometer is 

small. Figure 3 shows the turbine and meteorological tower locations as well as nearby 

obstructions and topographical features of the site. Table 2 gives sizes and distances of nearby 

obstructions. 

Figure 3. Map of the test site
6 

Table 2. Structures close to test turbine

Designation

Bearing

from

Test 

Turbine

(degrees T)

Distance from

Test Turbine

(m)

Obstruction

Height

(m)

Rotor

Diameter or

Obstruction

Width

(m)

Met B 290 107.5 18.2 0.4

Data shed 292 207.5 3.1 7.0

ARE 2 157.6 31.0 7.3

Met A 344 184.9 31.0 0.4

Mariah 227 168.9 6.1 1.2

Met C 236 184.5 4.6 0.4

NREL completed a site assessment to determine if the site fails the requirements of Annex A of 

the Standard and would therefore require a site calibration. Table 3 shows the results from the 

site assessment, which confirm that a site calibration was not required.

Table 3. Criteria for test site without site calibration

Description Distance Sector

(deg)

Test Site 

Condition

Pass/Fail

Maximum slope of best fit plane <3% <2 L 360 2.9% Pass

Maximum variation from best fit plane 

<0.08 D

<2 L 360 0.01 Pass

Maximum slope of best fit plane <5% 2–4 L In 1.2% Pass

Maximum variation from best fit plane 

<0.15 D

2–4 L In 0.02 Pass

Steepest slope maximum <10% 2–4 L Out 2.3% Pass

Maximum slope of best fit plane <10% 4–8 L In 1.2% Pass

Maximum variation from best fit plane 

<0.15 D

4–8 L In 0.02 Pass

No neighboring and operating turbines <2 Dn 360 0 Pass

No obstacles <2 De 360 0 Pass

D = test turbine rotor diameter 

L = distance between test turbine and meteorological tower 

De = equivalent diameter of obstacle 

In = inside preliminary measurement sector 

Out = outside preliminary measurement sector 

The Gaia-Wind 11-kW was connected to the electrical grid at a nominal voltage of 480 VAC at a 

frequency of 60 Hz. The grid tolerances are 5% for voltage amplitude and 1% for frequency. 
7 

5. Description of Test Equipment

All test equipment was calibrated; Appendix B contains the calibration sheets. Table 4 shows 

the equipment used and calibration due dates. Figure 4 depicts the placement of the 

meteorological instruments on the tower. The primary anemometer was sent out for 

recalibration after the test period. The difference between the pre-test and post-test calibrations 

was within the tolerances allowed by the Standard. 

Table 4. Equipment used in the power performance test

Instrument Make and Model Serial Number Calibration Due Date

Power transducer Ohio Semitronics, DMT 1040E 06091046 February 15, 2010

Current transformers Ohio Semitronics, 12974 001293045

001235428

001293049

Calibrated with power 

transducer

Primary anemometer Thies, First Class 0707890 April 7, 2009

Reference anemometer NRG, Max 40 179500049023 In situ

Wind vane Met One, 020C with Aluminum 

Vane

X4357 April 7, 2009

Pressure sensor 

(replaced during test)

Vaisala, PTB101B C1040014

T5030003

October 29, 2008

August, 26 2009

Temperature sensor 

(replaced during test)

Met One, T200 0890084

0789021

October 29, 2008

October 10, 2009

Precipitation sensor Campbell Scientific, 237 None In situ

Data acquisition 

system

Compact DAQ w/LabView 

cDAQ backplane

NI 9229

NI 9217

NI 9205

12E4DA3

12CBC7A

12BFEE2

12E9C99

August 14, 2008

July 20, 2008

October 8, 2008

Modules post-test 

calibrated on May 5, 

2009, were in 

compliance
8

Figure 4. Meteorological tower and instruments

To ensure that only data obtained during normal operation of the turbine are used in the 

analysis, and to ensure that data are not corrupted, NREL excluded data sets from the database 

under the following circumstances:

• External conditions other than wind speed are out of the normal range for turbine 

operation.

• The turbine cannot operate because of a turbine fault condition.

• The turbine is manually shut down or in a test or maintenance operating mode.

Two methods are used to track when any of these conditions occur during the test. In the first 

method, the logbook will be checked for such events. The turbine controller provides two status 

signals that indicate when the turbine is available or braked. In the second method, these status 

signals are checked in the data file during analysis. 
9

6. Description of Test Procedure

NREL conducted the test according to the procedures in the Standard. The sampling rate was 

10 kHz, decimated to 40 Hz. The averaging time was 1 minute for the mean values. NREL also 

collected standard deviation, minimum, and maximum values for each averaging period. 

Only database A is reported because the turbine did not reach cut-out wind speeds during the 

test period. 

Table 5 gives the uncertainty sources and values used in the analysis. 

Table 5. Uncertainty values used in the analysis

Component Uncertainty Source

Power

Current sensor/signal conditioner 15.36 W Specifications

Power transducer 0.09% Specifications

Data acquisition 56W +0.08% Specifications

Resistor 0.01% Specifications

Wind Speed

Calibration 0.01 m/s Calibration sheet

Operational characteristics 0.05 m/s +0.52% IEC equation (I.2)

Mounting effects 1.00% Assumption

Terrain effects 2.00% IEC

Data acquisition < 0.01 m/s Assumption

Temperature

Temperature sensor 0.15 °C Specifications

Radiation shielding 1.15 °C Assumption

Mounting effects 0.06 °C IEC method

Data acquisition 0.35 °C Specifications

Air Pressure

 Pressure sensor 0.20 kPa Specifications

Mounting effects < 0.01 kPa IEC method

Data acquisition 0.06 kPa Specifications

The turbine status signals for the Gaia-Wind 11-kW originate from the turbine controller. The 

status signals indicated whether the turbine was available or braked. 
10

7. Test Results

7.1.Tabular Results of Power Performance Test 

Table 6 through Table 9 list the power performance test results. Table 6 shows the binned 

power performance results at sea-level normalized air density. Table 7 shows the binned power 

performance results at the site average air density for the NWTC. 
11 

Table 6. Performance at sea-level air density, 1.225 kg/m3

Measured Power Curve (Database A) 

Reference Air Density: 1.225 kg/m3 Category A 

Standard 

Uncertainty 

(kW) 

Category B 

Standard 

Uncertainty 

(kW) 

Combined 

Standard 

Uncertainty

(kW) 

Bin 

(m/s) 

Wind 

Speed 

(m/s) 

Normalized 

Power 

Output 

(kW) 

Cp Number 

of 

1-Minute

Data 

Sets 

3 3.00 –0.10 –0.05 7347 0.00 0.06 0.06 

3.5 3.49 –0.11 –0.03 6270 0.00 0.06 0.06 

4 3.99 0.31 0.06 5193 0.01 0.11 0.11 

4.5 4.49 1.15 0.16 3951 0.01 0.20 0.20 

5 4.99 2.28 0.23 3021 0.02 0.29 0.29 

5.5 5.49 3.67 0.27 2381 0.03 0.38 0.38 

6 5.99 5.00 0.29 2017 0.03 0.40 0.40 

6.5 6.49 6.27 0.28 1706 0.03 0.41 0.41 

7 7.00 7.57 0.27 1455 0.03 0.44 0.44 

7.5 7.49 8.70 0.25 1358 0.03 0.42 0.42 

8 7.99 9.80 0.24 1142 0.03 0.43 0.43 

8.5 8.49 10.77 0.22 970 0.03 0.41 0.41 

9 9.00 11.67 0.20 873 0.03 0.39 0.39 

9.5 9.50 12.36 0.18 713 0.04 0.32 0.32 

10 10.00 13.12 0.16 604 0.04 0.37 0.37 

10.5 10.49 13.69 0.15 520 0.03 0.30 0.30 

11 11.00 14.15 0.13 417 0.04 0.25 0.25 

11.5 11.49 14.59 0.12 336 0.04 0.26 0.26 

12 12.00 14.80 0.11 317 0.04 0.15 0.15 

12.5 12.49 14.90 0.09 280 0.06 0.11 0.13 

13 13.00 15.00 0.08 225 0.05 0.11 0.12 

13.5 13.49 14.93 0.08 187 0.06 0.10 0.12 

14 13.99 14.80 0.07 180 0.07 0.13 0.15 

14.5 14.48 14.60 0.06 146 0.08 0.16 0.18 

15 15.00 14.40 0.05 117 0.10 0.17 0.19 

15.5 15.48 14.49 0.05 100 0.10 0.11 0.15 

16 16.03 14.42 0.04 87 0.09 0.10 0.14 

16.5 16.50 14.15 0.04 70 0.13 0.24 0.27 

17 16.99 14.24 0.04 66 0.10 0.12 0.16 

17.5 17.50 14.13 0.03 59 0.10 0.13 0.16 

18 17.99 14.08 0.03 53 0.10 0.10 0.14 

18.5 18.48 13.91 0.03 31 0.07 0.17 0.18 

19 18.99 14.00 0.03 25 0.08 0.12 0.14 

19.5 19.45 14.11 0.02 13 0.11 0.14 0.18 

20 19.92 13.74 0.02 10 0.10 0.38 0.39 
12 

Table 7. Performance at site average density, 0.95 kg/m3

Measured Power Curve (Database A) 

Reference Air Density: 0.95 kg/m3 Category A Category B Combined 

Bin 

(m/s) 

Wind 

Speed 

(m/s) 

Normalized 

Power 

Output 

(kW) 

Cp Number 

of 

1-Minute

Data 

Sets 

Standard 

Uncertainty 

(kW) 

Standard 

Uncertainty 

(kW) 

Standard 

Uncertainty 

(kW) 

3 3.00 –0.08 –0.04 7347 0.00 0.06 0.06 

3.5 3.49 –0.08 –0.03 6270 0.00 0.06 0.06 

4 3.99 0.24 0.06 5193 0.01 0.09 0.09 

4.5 4.49 0.89 0.16 3951 0.01 0.16 0.16 

5 4.99 1.77 0.23 3021 0.02 0.23 0.23 

5.5 5.49 2.84 0.27 2381 0.02 0.30 0.30 

6 5.99 3.88 0.29 2017 0.02 0.31 0.31 

6.5 6.49 4.86 0.28 1706 0.03 0.32 0.32 

7 7.00 5.87 0.27 1455 0.03 0.34 0.34 

7.5 7.49 6.75 0.25 1358 0.02 0.33 0.33 

8 7.99 7.60 0.24 1142 0.02 0.33 0.33 

8.5 8.49 8.35 0.22 970 0.02 0.32 0.32 

9 9.00 9.05 0.20 873 0.03 0.30 0.30 

9.5 9.50 9.59 0.18 713 0.03 0.25 0.25 

10 10.00 10.17 0.16 604 0.03 0.29 0.29 

10.5 10.49 10.62 0.15 520 0.03 0.24 0.24 

11 11.00 10.98 0.13 417 0.03 0.20 0.20 

11.5 11.49 11.32 0.12 336 0.03 0.20 0.21 

12 12.00 11.48 0.11 317 0.03 0.12 0.12 

12.5 12.49 11.56 0.09 280 0.05 0.09 0.11 

13 13.00 11.63 0.08 225 0.04 0.09 0.10 

13.5 13.49 11.58 0.07 187 0.05 0.09 0.10 

14 13.99 11.48 0.07 180 0.05 0.11 0.12 

14.5 14.48 11.33 0.06 146 0.06 0.13 0.15 

15 15.00 11.17 0.05 117 0.08 0.13 0.15 

15.5 15.48 11.23 0.05 100 0.08 0.10 0.12 

16 16.03 11.18 0.04 87 0.07 0.09 0.11 

16.5 16.50 10.97 0.04 70 0.10 0.19 0.21 

17 16.99 11.04 0.04 66 0.08 0.10 0.13 

17.5 17.50 10.96 0.03 59 0.08 0.10 0.13 

18 17.99 10.92 0.03 53 0.08 0.09 0.12 

18.5 18.48 10.79 0.03 31 0.05 0.14 0.14 

19 18.99 10.86 0.03 25 0.06 0.10 0.12 

19.5 19.45 10.94 0.02 13 0.09 0.12 0.15 

20 19.92 10.65 0.02 10 0.08 0.30 0.31 
13

Table 8 shows the annual energy production at sea-level normalized air density. Table 9 shows 

the annual energy production (AEP) at the site average air density at the NWTC.

Table 8. Annual energy production at sea-level density, 1.225 kg/m3

Estimated annual energy production, database A (all valid data)

Reference air 

density: 1.225 kg/m^3

Cut-out wind 

speed: 25.00 m/s

Hub height annual 

average wind 

speed (Rayleigh)

AEP-measured Standard Uncertainty 

in AEP-measured AEP-extrapolated

Complete if AEP 

measured is at least 

95% of AEP 

extrapolated

m/s kWh kWh % kWh

4 17,716 1,693 10% 17,716 Complete

5 32,122 2,093 7% 32,122 Complete

6 46,292 2,284 5% 46,313 Complete

7 58,690 2,328 4% 58,893 Complete

8 68,525 2,286 3% 69,394 Complete

9 75,474 2,199 3% 77,764 Complete

10 79,617 2,089 3% 84,067 Incomplete

11 81,326 1,968 2% 88,411 Incomplete

AEP measured assumes zero power between highest bin and cutout

AEP extrapolated assumes power in last bin between last bin and cutout

Table 9. Annual energy production at site average density, 0.95 kg/m3

Estimated annual energy production, database A (all valid data)

Reference air density: 0.95 kg/m^3

Cut-out wind speed: 25.00 m/s

Hub height annual 

average wind 

speed (Rayleigh)

AEP-measured

Standard 

Uncertainty in 

AEP-measured

AEP-extrapolated

Complete if AEP 

measured 

is at least 95% of AEP 

extrapolated

m/s kWh kWh % kWh

4 13,739 1,381 10% 13,739 Complete

5 24,911 1,679 7% 24,911 Complete

6 35,900 1,820 5% 35,916 Complete

7 45,515 1,850 4% 45,672 Complete

8 53,142 1,816 3% 53,816 Complete

9 58,531 1,748 3% 60,307 Complete

10 61,744 1,661 3% 65,195 Incomplete

11 63,069 1,566 2% 68,564 Incomplete

AEP measured assumes zero power between highest bin and cutout

AEP extrapolated assumes power in last bin between last bin and cutout
14

7.2.Graphical Results Power Performance Test 

Figure 5 through Figure 11 show the results of the power performance test. Figure 5 shows a 

plot of the binned power curve normalized to sea-level air density. 

Figure 5. Power curve at sea-level density, 1.225 kg/m3

-2

0

2

4

6

8

10

12

14

16

0 2 4 6 8 10 12 14 16 18 20

Wind Speed (m/s)

Power (kW), Normalized to Sea Level Air Density 
15

Figure 6 shows a plot of the binned power curve at the site average air density during the test 

period.

Figure 6. Power curve at site average density, 0.95 kg/m3

-2

0

2

4

6

8

10

12

14

0 2 4 6 8 10 12 14 16 18 20

Wind Speed (m/s)

Power (kW), Normalized to Site Specific Air Density
16

Figure 7 shows a scatter plot of statistics for power for the turbine.

Figure 7. Scatter plot of mean, standard deviation, minimum, and maximum power data

Multiple power curves appear at the higher wind speeds. NREL investigated the cause but did 

not find it during testing. NREL changed two contactors in the controller during the test, but this 

did not alter the performance of the turbine. The contactor replacement did not cause the 

multiple power curves.
17

Figure 8 shows a plot of the binned coefficient of performance as a function of wind speed at 

sea-level normalized air density. 

Figure 8. Coefficient of power at sea-level density, 1.225 kg/m3

0%

5%

10%

15%

20%

25%

30%

0 2 4 6 8 10 12 14 16 18 20

Wind speed (m/s)

Cp
18

Figure 9 shows a scatter plot and binned turbulence intensity as a function of wind speed. 

Figure 9. Wind turbulence intensity as a function of wind speed
19

Figure 10 shows a scatter plot of wind speed and turbulence intensity as a function of wind 

direction. 

Figure 10. Wind speed and turbulence intensity as a function of wind direction for the 

measurement sector
20

Figure 11 shows a scatter plot and binned values of rotor speed as a function of wind speed.

Figure 11. Rotor speed as a function of wind speed (1-minute averages) and binned 

values
21

8. Deviations and Exceptions

8.1 Deviations from the Standard

The current transformers are not compliant with IEC 60044-1 but do exceed the minimum 

accuracy required by the standard.

8.2 Exceptions to NWTC-CT Quality Assurance System

The data acquisition modules were used beyond the calibration due date. The modules were 

post-test calibrated and found to be in compliance within the specifications. Appendix B includes 

the post-test calibration sheets.
22

A. Appendix - Photographs of the Test Site from the Turbine Base
23

Figure A.1. Southwest

Figure A.2. South–southwest
24

Figure A.3. South

Figure A.4. Southeast
25

Figure A.5. East

Figure A.6. East–northeast
26

Figure A.7. Northeast

Figure 12. North
27

Figure A.9. Northwest

Figure A.10. West
28

B. Appendix - Equipment Calibration Sheets

Figure B.1. Power transducer calibration sheet
29

Figure B.2. Primary anemometer calibration sheet
30

Figure B.3. Primary anemometer calibration sheet II
31

Figure B.4. Wind vane calibration sheet
32

Figure B.5. RTD probe calibration sheet I
33

Figure B.6. RTD probe calibration sheet II
34

Figure B.7. Pressure transmitter calibration sheet
35

Figure B.8. NI 9229 data acquisition module calibration sheet I
36

Figure B.9. NI 9217 data acquisition module calibration sheet I
37

Figure B.10. NI 9205 data acquisition module calibration sheet I
38

Figure B.11. NI 9229 data acquisition module calibration sheet II
39

Figure B.12. NI 9217 data acquisition module calibration sheet II
40

Figure B.13. NI 9205 data acquisition module calibration sheet II
F1147-E(10/2008)

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4. TITLE AND SUBTITLE

Wind Turbine Generator System Power Performance Test Report 

for the Gaia-Wind 11-kW Wind Turbine

5a. CONTRACT NUMBER

DE-AC36-08-GO28308

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A. Huskey, A. Bowen, and D. Jager

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NREL/TP-500-46151

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WER94501

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1617 Cole Blvd.

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National Technical Information Service

U.S. Department of Commerce

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Springfield, VA 22161

13. SUPPLEMENTARY NOTES

14. ABSTRACT (Maximum 200 Words)

This test is being conducted as part of the U.S. Department of Energy’s (DOE) Independent Testing project. It is a 

power performance test that the National Renewable Energy Laboratory (NREL) conducted on the Gaia-Wind 11-kW 

small wind turbine.

15. SUBJECT TERMS

Gaia wind turbine; power performance test; 11-kW; small wind turbine

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OF ABSTRACT

UL

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b. ABSTRACT

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c. THIS PAGE

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Standard Form 298 (Rev. 8/98)

Prescribed by ANSI Std. Z39.18