Small Wind Turbine Tests and Testing Approach
The National Renewable Energy Laboratory (NREL) has testing capabilities that are accredited by the American Association of Laboratory Accreditation (A2LA). Currently, NREL is one of only two facilities in the United States that are A2LA accredited.
The suite of tests conducted on small wind turbines includes acoustic noise emissions, duration, power performance, power quality, and safety and function. Learn about NREL's small wind turbine research projects. Each of the tests is briefly described below. Tests are performed to International Electrotechnical Commission (IEC) standards and in compliance with NREL's A2LA-accredited Quality Assurance (QA) system.
Acoustic Noise Emissions
Acoustic noise emissions testing summarizes typical noise levels emitted from the turbine at different wind speeds. Sound data are recorded (one tower height plus half a rotor diameter downwind from the tower base) and processed using Noiselab software. Noise testing is performed according to IEC Standard 61400-11.
Duration
Duration testing is performed to summarize the turbine's operation over long time periods. Test data are sorted monthly into time classes specified by the standard and submitted to the client in an informal report. Duration testing is performed according to IEC Standard 61400-2.
Power Performance
Power performance testing produces a power vs. wind speed graph to summarize the turbine's power generation performance at different wind speeds. This test is performed according to IEC Standard 61400-12-1, referencing Appendix H for small turbines. Data are analyzed for rejections based on wind direction, turbine status, and instrument readings, and then compiled through an Excel-based program to produce a power curve.
Power Quality
Power quality testing is performed according to IEC Standard 61400-21. This testing includes assessment of power, flicker, and harmonics levels for compliance with the standard. For small turbines, power quality tests are performed for 3-phase systems.
Safety and Function
Safety and function testing is performed to verify that the turbine displays its designed behavior as represented by the manufacturer. Features tested are drawn from the wind turbine documentation. The testing is conducted in accordance with IEC Standard 61400-2.
