Wind Sensor Comparison—Ultrasonic versus Wind Vane/Anemometer

Accurate measurements of wind direction and wind speed are crucial at nuclear power plants for making transport and diffusion estimates. Historically, the Tennessee Valley Authority (TVA) made wind measurements using the traditional wind vane/anemometer system because these instruments both satisfied accuracy requirements and were much less expensive than alternative methodologies. However, when age and difficulty in obtaining spare parts required replacement of wind measurement instruments, TVA examined other methodologies. An ultrasonic sensor was selected because accuracy requirements were met, instrument costs were similar to a wind vane/anemometer system, maintenance costs will be reduced, and the TVA data collection system can be easily adapted and streamlined to use the sensor. Prior to selecting the ultrasonic sensor as a replacement for the wind vane/anemometer system, TVA performed a series of tests to document the comparability of the two systems. These included laboratory evaluations using wind tunnels and side-by-side comparisons between sensors installed on a 91-meter tower. The overall conclusion is that the ultrasonic wind sensor is equivalent to the wind vane/anemometer system for the intended application by TVA. This paper describes the tests, summarizes results, identifies lessons learned, and discusses design considerations.