English Farms & Upland Prairie Wind Farms, Iowa

Location: Poweshiek, Clay, and Dickinson Counties, Iowa
Owner: Alliant Energy
Operator: AWS TruePower (a UL Company)

HGC Engineering was retained by AWS TruePower to complete sound level testing on several wind turbines located in Iowa.

Sound testing in accordance with the International Electrotechnical Commission 61400-11-2018 (Edition 3.1) Wind turbine generator systems – Part 11: Acoustic noise measurement techniques (IEC 61400-11) was completed to determine the sound power output of three General Electric wind turbine generators.

HGC Engineering employed a sophisticated RoBin measurement system, developed by Wolfel, to conduct the IEC 61400-11 testing. This system provides the benefit of wireless communications between the 10 m height anemometer, the sound level analyser, and the turbine data collection system, providing real-time feedback on the status of the measurements. Data was collected and binned automatically, with user input identifying the collected data as ambient sound, interfering sound, or turbine sound, minimizing lost data. The principal advantage of a system capable of real time analysis, is that HGC Engineering knows in the field when the required data points are collected and can have immediate feedback if there are problems with any of the data sources, eliminating unnecessary site time or repeated test visits.

Acoustical Engineering Services Included:

• Sound power testing to the IEC 61400-11 standard on several wind turbine generators
• Testing accredited to ISO 17025