Powering Europe - European Wind Energy Association

turningtheenergychallengeintoacompetitiveadvantage
factors. The changing weather makes millions of people
switch on and off heating or lighting. Millions of
people in Europe switch on and off equipment that
demands instant power - lights, TVs, computers.
Power stations, equipment and transmission lines
break down on an irregular basis, or are affected by
extremes of weather such as drought. Trees fall on
power lines, or the lines become iced up and cause
sudden interruptions of supply. The system operators
need to balance out planned and unplanned changes
with a constantly changing supply and demand in
order to maintain the system’s integrity. Variability in
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electricity is nothing new; it has been a feature of the
system since its inception.
Both electricity supply and demand are variable. The
issue, therefore, is not the variability or intermittency
per se, but how to predict, manage and ameliorate variability
and what tools can be utilised to improve efficiency.
Wind power is variable in output but the variability
can be predicted to a great extent. This does not
mean that variability has no effect on system operation.
It does, especially in systems where wind power
meets a large share of the electricity demand.
Powering Europe: wind energy and the electricity grid