Calculating annualized sound levels for a wind farm

Modeling done for wind farms usually focuses on calculating a worst-case short term average sound level. However, the impact to homes is not simply defined by a single meteorological condition. Rather, a more complete picture of the impacts is given by calculating sound levels under various meteorological conditions that occur during the year. The actual sound level at a receiver will depend on variations in atmospheric stability, wind speed, wind direction, and other parameters that change hourly. This paper will describe a method to calculate hourly sound pressure levels for individual receivers over the course of an 8760 h year and give examples of different wind farm configurations and how they affect annualized sound levels.