Environmental Engineering Reference
In-Depth Information
Figure 2.3: Solar and Wind Provide a Small, Unreliable Fraction of Germany's
Electricity
Sources: European Energy Exchange Transparency Platform Data (2013); Federal Statistical Office of Germany
How, then, can so many say that solar or wind generates over 50 percent of Germany's energy? What
they are referring to is the fact that because solar and wind are so variable, at any given
moment
solar can
generate 50 percent of the electricity being used. It can also generate 0 percent of the electricity generated
at any given moment. Here is a graph of German solar and wind production in April 2013 based on the
average amount of electric power generated every fifteen minutes. Notice that sometimes the combined
output of solar and wind is relatively high—and sometimes it is nothing; that is the nature of an intermit-
tent, unreliable source.
Figure 2.4: Solar and Wind: The Closer You Look, the Less Reliable They Are
