Technical Support
NREL's specialized facilities and personnel at the National Wind Technology Center (NWTC) provide the wind industry with technical support that is viewed as critical to the development of advanced wind turbine technologies. With its unique testing capabilities, the center is able to provide a level of technical support that is not usually available to industry members and that would be difficult to duplicate.
NREL works with its industry partners to verify the performance and reliability of wind turbines that range in size from 400 Watts to 2 megawatts. Engineers conduct tests on components and full-scale turbines in laboratory environments and in the field that produce test data that can be used to validate turbine design codes and simulations to further advance turbine designs.
The structural testing of a turbine blade.
As a facility accredited through the American Association of Laboratory Accreditation (A2LA) to perform several critical tests, NREL provides the high quality testing required by wind turbine certification agencies, financial institutions, and other organizations throughout the world. (See details of NREL’s scope of accreditation (PDF 123 KB) from A2LA’s Web site.) Download Adobe Reader.
NREL works with industry members through support from the U.S. Department of Energy Wind Program and through cooperative and work for other agreements. For more information on working with NREL see Working with Us.
Structural Testing
Researchers at the NWTC structural test facility, which is accredited by A2LA to perform blade tests in accordance with IEC 61400-23, conduct structural tests on full-scale wind turbine blades for subcontractors and industry partners. The facility's capabilities include fatigue testing, ultimate static strength testing, and several nondestructive techniques, such as photoelastic stress visualization, thermographic stress visualization, and acoustic emissions.
Dynamometer Testing
NREL's 2.5-MW dynamometer is the only facility of its kind in the world and allows researchers to conduct full-system tests and identify critical integration issues for industry partners.
NREL's 225-kW and 2.5-MW dynamometer test facilities provide industry with a way to conduct a range of system tests that cannot be duplicated in the field. These tests include gearbox fatigue, wind turbine control simulations, transient operation, and generator and power system component efficiency and performance tests. As the only facility of its kind in the world, NREL's 2.5-MW dynamometer conducts full-system tests and identifies critical integration issues before field deployment, giving the U.S. industry an edge over strong European competition.
NREL's small, 225-kW dynamometer is suitable for testing wind turbine components for turbines rated up to nearly 200 kW. Such turbine components include subsystems, generators/alternators, gearboxes, mechanical or electro-dynamic brakes, power electronics, control systems, and software. The facility is capable of 225-kW peak power and shaft speeds up to 4,140 revolutions per minute (rpm). Test objectives might include performance, system integration (generator, power electronics, and grid), software development, or accelerated life testing.
Field Testing
NREL is working closely with companies like Clipper Windpower Technology to develop this 2.5-MW turbine, shown in field testing.
Field testing encompasses a wide range of activities that provide high-quality testing to support wind technology projects. Such testing is typically conducted on full-scale wind turbine systems installed in the field, although it sometimes targets specific components and subsystems.
A2LA has accredited NREL to perform the following tests in accordance with international standards:
- Acoustic Noise to IEC 61400-11 and MEASNET
- Power Performance to IEC 61400-12-1 and MEASNET
- Mechanical Loads to IEC 61400-13
- Power Quality to IEC 61400-21 and MEASNET
- Duration Testing to IEC 61400-2
- Safety and Function to IEC 61400-2
The NREL accreditation scope is available (PDF 33 KB). Download Adobe Reader.
Other non-accredited tests include dynamic characterization testing and modal testing. In addition, NWTC has conducted many tests that support turbine R&D, most notably the "NREL Unsteady Aerodynamics Experiment in the NASA-Ames Wind Tunnel: A Comparison of Predictions to Measurements" (PDF 1.19 MB) that acquired data sets for more than 1,700 different turbine conditions. These data are a valuable resource for developing and validating wind turbine aerodynamic codes. Download Adobe Reader.
