Letter Report No CRT-003 Project No. G

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3933 US Route 11 Cortland, NY 13045 Telephone: (607) 753-6711 Facsimile: (607) 753-1045 www.intertek.com Letter Report No. 100413407CRT-003 Project No. G100413407 Mr.

1 3933 US Route 11 Cortland, NY Telephone: (607) Facsimile: (607) Letter Report No CRT-003 Project No. G Mr. Steve Turek Phone: Wind Turbine Industries, Corporation Fax: Industrial Cir SE Prior Lake, MN Subject: Power performance test report for the Jacobs Wind Energy System tested at the Intertek Small Wind Regional Test Center (RTC). Dear Mr. Turek, This Test Report represents the results of the evaluation and tests of the above referenced equipment under Intertek Project No. G , as part of the NREL Subcontract Agreement No. AEE , to the requirements contained in the following standard: AWEA 9.1 Small Wind Turbine Performance and Safety Standard December 2009 IEC Wind Turbines - Part 12-1: Power performance measurements of electricity producing wind turbines; December 2005 This investigation was authorized through signed Intertek Quote No , dated May 13 th, A production sample was installed at the Intertek RTC on October 25 th, Power performance testing began on December 1 st, 2011 and data collection continued through February 29 th, This Test Report completes the power performance testing phase of the Jacobs Wind Energy System under Intertek Project No. G If there are any questions regarding the results contained in this report, or any of the other services offered by Intertek, please do not hesitate to contact the undersigned. Please note, this Test Report on its own does not represent authorization for the use of any Intertek certification marks. Completed test reports for Duration, Acoustics, and Strength and Safety are required to complete the AWEA certification process. Completed by: Joseph M Spossey Reviewed by: Tom Buchal Title: Project Engineer Title: Senior Staff Engineer Signature: Signature Page 1 of 54 This report is for the exclusive use of Intertek s Client and is provided pursuant to the agreement between Intertek and its Client. Intertek s responsibility and liability are limited to the terms and conditions of the agreement. Intertek assumes no liability to any party, other than to the Client in accordance with the agreement, for any loss, expense or damage occasioned by the use of this report. Only the Client is authorized to permit copying or distribution of this report and then only in its entirety. Any use of the Intertek name or one of its marks for the sale or advertisement of the tested material, product or service must first be approved in writing by Intertek. The observations and test results in this report are relevant only the sample tested. This report by itself does not imply that the material, product or service is or has ever been under an Intertek certification program.

2 Wind Turbine Generator System Power Performance Test Report for the WTIC Jacobs Wind Energy System tested at Intertek Small Wind Regional Test Center Page 2 of 54

3 1.0 Background This test is conducted as part of the Department of Energy / National Renewable Energy Laboratory (DOE/NREL) Subcontract Agreement No. AEE for the testing of small wind turbines at regional test centers. The Wind Turbine Industries Corporation (WTIC) Jacobs Wind Energy System was accepted into this program by Intertek and DOE/NREL. The full scope of type testing and AWEA Certification provided by Intertek for the Jacobs horizontal-axis wind turbine is covered by this agreement. This test report is a summary of the results of power performance testing, and is one of four tests to be performed on the Jacobs turbine; the other three being duration, safety and function, and acoustics. Results for these other tests are summarized in their respective Test Reports. The Jacobs turbine is installed at Test Station #5 at the Intertek RTC in Otisco, NY. The Jacobs is designed for grid-connected power delivery, with a maximum power output of 20 kw. It is designed as a Class II upwind turbine, with speed and power control through side furling and a centrifugal variable pitch governor. The blades of the Jacobs drive the low speed shaft of an offset hypoid gearbox with 6.1:1 ratio. The gearbox high-speed shaft drives a brushless three-phase AC synchronous generator with outbound exciter. The generator is rated for VAC operation up to 25 kva. Grid interconnect is provided by a Nexus Nex20 inverter, which fully converts the generator output to single phase 240 VAC for connection to a single/split phase grid. The Nex20 inverter is specifically designed for the Jacobs Wind Energy System. The test tower and foundation were designed and approved by ROHN Products LLC. NYS Professional Engineer stamped tower and foundation designs were also provided by ROHN Products LLC. The designs were based off of the Subsurface Investigation and Geotechnical Evaluation detailed in Atlantic Testing Laboratories report number CD3119E for the Intertek RTC. The electrical network at the testing location is single/split phase 120/240 VAC at 60 Hz. Refer to the wiring diagram in Appendix A for additional detail. A summary of the test turbine configuration and manufacturer s declared ratings can be found in Table 1 below. 2.0 Test Objective The purpose of this test is to quantify the power performance characteristics of the Jacobs turbine shown on Page 2, and described in detail in Table 1. These characteristics are primarily defined by the measured power curve, which provides the basis for estimates on Annual Energy Production. The power curve is determined by simultaneous measurements of turbine output power and wind speed for a given period of time. The required database is sufficient to understand the power performance characteristics of the Jacobs in real world freestream airflow. 3.0 Test Summary This test was conducted in accordance with the American Wind Energy Association Small Wind Turbine Performance and Safety Standard dated December, The power performance test was also conducted in accordance with the first edition of the International Electrotechnical Commission s (IEC) Wind Turbines - Part 12-1: Power performance measurements of electricity producing wind turbines, IEC Annex H dated December, Hereafter, these testing standards and their procedures are referred to as the Standards. Figure 1 is the summary of results from the power performance test conducted on the Jacobs turbine. In Figure 1, power is normalized to sea-level air density. The amount of test data analyzed to produce Figure 1 is sufficient to meet the database requirements of the Standards. Table 1 identifies the configuration of the wind turbine system tested for this report. The power measurement equipment used for measurement of electric power consists of both a current transformer and power transducer used to measure current and voltage to determine electric power output in accordance with the Standards. The location of power measurement equipment encompasses the combined consumption and production of the entire turbine system. Refer to Appendix A for wiring diagrams. Page 3 of 54

4 Figure 1 - Power curve summary Page 4 of 54

5 Wind Turbine Industries, Corporation Turbine manufacturer and address Industrial Circle S.E. Prior lake, Minnesota Model Wind Turbine Industries, Corporation Gearbox manufacturer Model: 20kW, Part Number: Serial Number: Offset hypoid design Gearbox specifications 6.1:1 gear ratio Winco Inc; Model 20PS4G-27 Generator manufacturer WTIC Part Number: Serial #: W kw, VAC, 0-40 Hz Generator specifications 3-phase, RPM Nexus Inverter manufacturer Model #: NEX20 Serial #: kw, 240 VAC, 60 Hz Inverter specifications TUV listed - UL 1741 Rotor diameter 9.4 m (31.0 ft.) verified by Intertek Hub height 35.9 m (117.0 ft 8.0 in.) Swept area 70.1 m 2 (755.0 ft 2 ) IEC SWT Class (I, II, III, or IV) II Tower type(s) Lattice Rated electrical power 20.0 kw Cut-in wind speed 4.5 m/s (10.1 mph) Rated wind speed 11.6 m/s (26.0 mph) Survival wind speed 53.6 m/s (120.0 mph) Rotor speed range rpm Fixed or variable pitch Variable Number of blades 3 Blade tip pitch angle 1 Advanced Aero Technologies. Inc Fiberglass Blade manufacturer SNs CGA1849, CGA1854, CGA1852 Proprietary System, Horner Display unit HON:1.13, Control system software Oztek Control Board DSP:1.03 Table 1 Test turbine configuration and manufacturer s declared specifications 4.0 Judgments, Exceptions, and Deviations There were no judgments, exceptions, or deviations from the Standards for the purposes of this test report. Page 5 of 54

6 5.0 Test Site Description 5.1 Test Site The RTC has class IV winds, and can accommodate turbines that produce 120V or 240V, 60 Hz power. It is on a hilltop, with previous agricultural land use, near the township of Otisco, NY. It was surveyed, analyzed and developed to be a test site for Intertek s customers. The Jacobs is tested at RTC site #5, which has no prominent obstructions in the valid measurement sector, as determined by obstacle assessment in accordance with the Standards. It was determined that site calibration was necessary due to the topographical variation at the RTC. A site calibration was performed in lieu of the terrain assessment due to known topographical variations. The resulting flow correction factors are applied to a contiguous data set for power performance results. The meteorological equipment tower is due south, 23.6 m (77.5 feet) from the turbine, exactly 2.5 times the diameter of the rotor, as recommended in the Standards. All buildings and potential obstacles are identified in the topographical survey map, and were considered during obstacle assessment. 5.2 Measurement Sector Figure 2 below is a topographical survey map that displays the final valid measurement sector resulting from the combination of obstacle assessment and site calibration in accordance with the Standards. Figure 2 also shows the location of the Jacobs and its measurement tower ( Met5 ). The preliminary obstacle assessment yielded an initial valid measurement sector of degrees true, but this was cut to a final valid sector of degrees true as a result of site calibration. Site calibration was required due to the local terrain not satisfying the criteria within the terrain assessment requirements of the Standards. The shaded area displays the excluded wind sector. A circle indicating 20 rotor diameters is also shown on the map.. Page 6 of 54

7 Figure 2 Topographical survey map and final valid measurement sector of the Jacobs test turbine Page 7 of 54

8 Table 2 below provides detail on obstacles that were determined to be significant as a result of the obstacle assessment. Based upon the results in Table 2, a valid measurement sector of degrees true was established prior to site calibration. Description Reference Point Distance Diameter Equivalent Bearing Start Invalid Sector Stop (m) (m) ( true) ( true) ( true) Jacobs Jacobs Met INVALID Sector = VALID Sector(s) = Table 2 Obstacles relative to the Jacobs and meteorological tower locations Site calibration was required due to the combination of average slope and terrain variations within 20 rotor diameters of the turbine tower. Table 3 below shows the results of the site calibration for the Jacobs power performance test, where: Direction = each 10-degree wind direction bin, in true degrees, considered during site calibration, Total Time = total number of hours of data collected in each wind direction bin, Velocity < 8 m/s = total number of hours where wind speeds are below 8 m/s in each wind direction bin, Velocity > 8 m/s = total number of hours where wind speeds are above 8 m/s in each wind direction bin, Turbine Velocity Average = average wind speed measured at the turbine location in each wind direction bin, Met5 Velocity Average = average wind speed measured at the meteorological tower location in each wind direction bin, Ratio = average flow correction factor due to terrain for each wind direction bin (ratio of wind speed at the wind turbine location divided by the wind speed at the meteorological tower location), Red text = INVALID sector resulting from obstacle assessment, Black text = VALID sector resulting from obstacle assessment, and Blue shade = FINAL VALID sector resulting from site calibration Page 8 of 54

9 Direction Direction Average Total Time Velocity < 8 m/s Velocity > 8 m/s Turbine Velocity Average Met5 Velocity Average ( true) ( true) (hours) (hours) (hours) (m/s) (m/s) Average of Ratios Table 3 Site calibration results The combined standard uncertainty of the wind speed ratio at 6 m/s, 10 m/s, and 14 m/s is m/s, m/s, and m/s respectively. Page 9 of 54

10 Figure 3 below plots the wind direction bin ratios that resulted from site calibration at the testing location. Figure 3 - Site calibration ratio binned data. Valid sector from degrees with respect to true north Page 10 of 54

11 6.0 Test Equipment Description Table 4 below shows the equipment that was used during the power performance testing of the Jacobs Serial numbers and instrument calibration details are also provided in the table. All instruments were properly calibrated according to the Standards for the duration of power performance testing identified in Figure 1. Calibration certificates are included in Appendix C. Description Manufacturer/Model Serial # / Asset # Primary anemometer Reference anemometer Wind vane Barometric pressure sensor Temperature/RH sensor Power transducer Current transducer Adolf Thies GmbH Adolf Thies GmbH Adolf Thies GmbH Vaisala PTB330 Adolf Thies GmbH * Ohio Semitronics DMT-1040EY44 Ohio Semitronics *Model # differs on calibration certificate; the model # listed in this table is correct **Intertek calibration database Asset #; PT and CT calibrated as a system Table 4 Equipment used in the power performance test Calibration date Calibration due date Sep Sep Sep Sep Aug Aug-2012 F Aug Aug Aug Aug-2012 A333** 24-Oct Oct-2012 A333** 24-Oct Oct-2012 A National Instruments cdaq-9178 backplane and NI /- 20 ma 8-channel current module are used for logging the outputs signals from the sensors in Table 4 above. A proprietary LabVIEW program is used to collect and filter data that is stored in raw and 1 Hz data files on the Intertek RTC site computer. Prior to testing, a signal verification procedure was carried out on the data acquisition system by Intertek to verify the signals of each transducer against recorded values from the LabVIEW program. Table 5 below summarizes the results of the signal verification. Page 11 of 54

12 Measurement NI 9203 Channel Primary windspeed 0 Reference windspeed Wind direction 2 Relative humidity 3 Temperature 4 Barometric Pressure Output power Injected Signal {ma} Measured Value {ma} Offset {ma} n/a 7 not used not used n/a Table 5 Signal verification results The data acquisition system is located inside the Intertek RTC control building; all signals are measured at this location. This is also the location of the turbine disconnect and grid-tie inverter, and thus is also where power measurements are made. The data is stored on two separate computers at the Intertek RTC, and also stored in the Intertek project file. The power measurement equipment is located inside the control building at an approximate wire run length of 91.4 meters (300 feet); which satisfies the required wire run length in the Standards. Figure 4 displays the arrangement of the meteorological tower with dimensions of instrument locations. The height above ground level to the centreline of the cups of the primary anemometer of meters is the same height above ground level as the hub height of the Jacobs The reference anemometer and the wind vane are installed at the same height of m, and the temperature and pressure sensors are installed at the same height of 21.5 m. No in situ comparison of anemometers was made during this test period. The primary method of anemometer calibration verification of post-test calibration was followed; calibration certificates are found in Appendix C. Page 12 of 54

13 Figure 4 Meteorological tower and instrument locations Page 13 of 54

14 7.0 Test Procedure 7.1 Data Collection Measurement procedures and data collection were conducted in accordance with the Standards. Data was sampled at the required rate of 1 Hz. The averaging period for all average, maximum, minimum, and standard deviation values was 1 minute, as required by the Standards. No turbine status signal is provided by the turbine controller; therefore, one was not monitored during this test. Meteorological data and the turbine output power signals were gathered by the NI 9203 module and stored in daily spreadsheet files on the control building computer. The spreadsheet files are where all analysis according to the Standards took place. The data was sorted per binning method described in the Standards based on 1 minute averaging of the measured, contiguous data. Only Database A is reported in this report. This is due to the fact that cut-out behaviour was not observed during the power performance test. 7.2 Data Rejection To ensure that only data obtained during normal operation of the wind turbine are used in the analysis, and to ensure data are not corrupted, selected data sets were excluded from the database under the following circumstances: External conditions other than wind speed are out of the operating range of the wind turbine, Turbine cannot operate because of a turbine fault condition, Turbine is manually shut down or in a test or maintenance operating mode, Failure or degradation (i.e. du to icing) of test equipment, Wind direction outside the measurement sector as defined in section 5.2 above, or Wind directions outside valid (complete) site calibration sectors as defined in section 5.2 above. No maintenance was performed on the Jacobs during the test period. 7.3 Data Normalization The 1 minute averaged data sets were normalized to sea-level air density, kg/m 3. A second normalization to site average air density was not required due to the fact that the average air density during the testing period was within the specified range of 0.05 kg/m 3 of sea-level air density. The calculated site average air density at the Intertek RTC for the measurement period was kg/m 3. Air density was determined from measured air temperature and air pressure according to Equation 1 from IEC Data normalization was then applied to the measured power output according to Equation 2 from IEC Determination of results The measured power curve is determined by applying the method of bins to the normalized data sets, using 0.5 m/s bins. Average values for wind speed and normalized power output for each bin were determined according to Equations 4 and 5 from IEC Annual energy production was estimated by applying the measured power curve to different reference wind speed frequency distributions. A Rayleigh distribution, which is identical to a Weibull distribution with a shape factor of 2, was used to reflect the wind speed frequency distribution. For determination of AEP, the availability of the wind turbine is assumed to be 100%. AEP estimations were made for hub height annual average wind speeds between 4 and 11 m/s according to Equations 6 and 7 from IEC Page 14 of 54

15 The power coefficient, C P, of the wind turbine was determined from the measured power curve according to Equation 7 from IEC Uncertainty Table 6 below summarizes the Category B uncertainty parameters for the power performance measurements. Total Category B uncertainty is obtained by combining each component s uncertainty using the root-sum-squared method. Combined uncertainty is the root-sum-squared combination of Category A and Category B uncertainties of power measurements. Final Category A, Category B, and combined uncertainties are presented in Table 7 in section 9 of this report. Component Uncertainty Source Power (Inverter) Voltage transducer N/A Current transformer 0.3 % Calibration Power transducer 0.3 % Calibration Data acquisition 0.66 % Manual Wind Speed Anemometer m/s Calibration Operational Characteristics m/s % IEC Terrain effects m/s* IEC Mounting effects 1.00 % Assumption Data Acquisition 0.66 % Assumption Temperature Temperature Sensor C Calibration Radiation Shielding C Calibration Mounting Effects C IEC Data Acquisition C Manual Pressure Sensor Pressure Sensor hpa Calibration Mounting Effects hpa IEC Data Acquisition hpa Manual Table 6 Uncertainty values used in the analysis *Range of site calibration uncertainties within the valid measurement sector Page 15 of 54

16 9.0 Test Results 9.1 Tabular results Table 7 below shows the normalized and averaged results of the power performance test for the Jacobs turbine. No normalization to test site average air density is required due to the site average density being within 0.05 kg/m 3 of sea-level air density. Bin Presentation of data in the measured power curve (database A) Reference air density: kg/m 3 Category A Normalized Power Standard Wind Speed output Cp Uncertainty Number of 1-Minute Data Sets Category B Standard Uncertainty Combined Standard Uncertainty (m/s) (m/s) (kw) (kw) (kw) (kw) Table 7 Jacobs performance at sea-level air density; kg/m 3 Page 16 of 54

17 Table 8 below summarizes the estimation of expected annual energy production (AEP) at sea-level air density. Estimated annual energy production, database A (all valid data) Reference air density: kg/m 3 Cut-out wind speed: m/s Hub height annual average AEP-Measured Standard Uncertainty wind speed AEP- Extrapolated Complete if AEP- Measured is at least 95% of AEP- Extrapolated m/s kwh kwh % kwh Complete Complete Complete Complete Complete Complete Incomplete Incomplete Table 8 Estimated annual energy production of the Jacobs at sea-level air density An indication of incomplete in the far-right column of Table 8 does not imply that the database for the test is incomplete. Incomplete means that AEP-Measured is not within 95% of AEP-extrapolated. AEP-extrapolated is an estimated extrapolation of annual energy production, where: AEP-Measured assumes zero power below cut-in wind speed and between the highest valid wind speed bin and cut-out wind speed, and AEP-Extrapolated assumes zero power below cut-in wind speed and constant power between the highest valid wind speed bin and cut-out wind speed. Page 17 of 54

18 9.2 Graphical results Figure 5 below shows the graphical results of the power performance test for the Jacobs The uncertainty of each wind speed bin is shown as error bars on the graph. Figure 5 Jacobs power curve at sea-level air density; kg/m 3 Page 18 of 54

19 Figure 6 below shows the 1 minute output power values for average, maximum, minimum, and standard deviation of sampled data. Figure 6 - Scatter plot of output power average, maximum, minimum, and standard deviation of 1 Hz data with 1 minute averaging. Page 19 of 54

20 Figure 7 below shows the coefficient of performance at sea-level air density. Figure 7 Coefficient of performance of the Jacobs with swept area of 70.1 m 2 at sea-level air density of kg/m 3 Page 20 of 54

21 Figure 8 below shows the turbulence intensity as a function of wind speed. The graph shows both sampled data and binned data. Figure 8 - Wind turbulence intensity as a function of wind speed Page 21 of 54

22 Figure 9 below displays both average wind speed measured by the primary anemometer and turbulence intensity as a function of wind direction. Figure 9 - Wind speed and turbulence intensity as a function of wind direction Page 22 of 54

23 A.0 Appendix The following sections can be found within this Appendix: A Wiring diagrams B Pictures of the valid measurement sector C Calibration certificates Page 23 of 54