This data is compiled from the previous 2 sections

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Average Wind Hours & Flow per Year     Assumptions

Wind Flow required for most wind turbines to deliver name plate rated power
is a speed of 30 mph,
average annual wind speeds are often less.


At slower wind speeds, the production falls off dramatically. If the wind speed decreases by half, power production decreases by a factor of eight.


On average, therefore, wind turbines do not generate near their capacity.
Industry estimates project an annual output of 30-40%,

but real-world experience shows that annual outputs of 15-30% of capacity are more typical.

For this estimation we will use the industry high
40% of the time = 3,500 hours per year


Also note, in support of the above estimation:

Erich Hau in Wind Turbines: Fundamentals, Technologies, Application, Economics

Springer, 2005,

reports that for economic comparison purposes:
wind turbines operate at full load for between 3,000 and 4,000 hours per year.

2010+     2015           2016+        Comparisons