Development of internationally agreed procedures for testing and evaluation of Wind Turbines is needed to aid the development of the industry and to strengthen confidence in the technology and prevent chaos in the market. 

When evaluating or testing a wind turbine, particularly for performance determination, one of the most critical measurements is that of wind speed.

Uncertainty in wind speed measurements, be they made during a site assessment, a site calibration or a wind turbine performance test, all contribute to the overall uncertainty in predicted annual energy yield.

In economic terms, this translates into financial risk and in turn into higher cost of energy. By adopting best practice in the design, selection, calibration, deployment and use of anemometry, uncertainty can be minimised.

There is no other branch of meteorology, science or technology where the importance of low uncertainty in wind speed measurement is as great as in wind energy. Until very recently there has been no clear guidance, even in standards relating to wind turbine testing, on best practice in the use of anemometry.

This document, drawing upon several years of experience and research by the authors aims to fill this gap.