Environmental Engineering Reference
In-Depth Information
assumed to be 30 m, at which the reference annual average wind speed
U
A
is 7.80 m/s. As-
suming the Weibull factors
C
and
k
are related to average wind speed as given in this table,
cost of energy is inversely proportional to the annual energy density
e
W
. As shown in Figure
2-20, a reduction of 1.0 m/s in the annual average wind speed can increase the cost of energy
by about 40 percent. Similarly, an increase of 1.0 m/s can decrease COE by almost 30 per-
cent.
The annual average wind speed at an individual wind turbine site may decrease as the
result of the operation of turbines upwind of it. This reduction in wind speed within the wind
power station itself is often referred to as a
wake effect
or
array effect
on performance and is
discussed in more detail in Chapter 6.
Search WWH ::
Custom Search