Environmental Engineering Reference
In-Depth Information
35
30
25
20
15
10
5
0
Jan
Mar
May
July
Sept
Nov
Wind variability in Germany. Percentage of electrical
demand delivered by all the wind turbines of E.ON Energie during
the year
fig. 13.1
. Averaged over the year, wind power delivered
%
of installed capacity. (Courtesy of E.ON Energie)
no wind farm puts out its rated capacity for very long or
even for a majority of the time.
Figure
shows the energy actually delivered by all
the wind turbines of the German utility E.ON Energie
during the year
.
as a fraction of the total electrical
energy produced by that utility. The fraction varies wildly
mainly because of the variable wind speed. The wind
turbines are spread over a large part of the German land
area so that when the wind is not blowing in one area it
may be blowing at another, but it is very rare for the wind
to blow at all sites hard enough to give
% of capacity
as the actual output. The real year-long average output
for this company
% of capacity.
The International Energy Agency (IEA) in Paris is
home to a
'
is wind turbines is
-country consortium called IEA Wind that
collects data and exchanges information and experience
