Environmental Engineering Reference
In-Depth Information
by time of day, and even by the second. Godfrey Boyle colorfully docu-
ments how a mass rush to brew tea at half time during the 1990 World Cup
Semi-inal between West Germany and England caused a demand spike of 2
GW over a 2-3 minute period.
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An electricity supply system must be able to
respond promptly to all these demand variations.
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his challenge is complicated by the fact that all power generation sys-
tems face hurdles in producing consistent energy lows and adjusting power
output to meet demand. his is important to note, because one of the chief
criticisms of wind power is that inconsistent power lows create costly power
management challenges. his can be true, but it is not a weakness that only
wind systems exhibit. Both nuclear and coal-ired plants, for example, can
break down, suddenly removing a major source of electricity supply. he
most prominent recent example pertains to Japan's nuclear power program
where the 50 remaining plants were taken oline for safety checks after the
Fukushima disaster.
Electricity generation technologies also difer in terms of ability to
respond to sudden demand luctuations. On one end of the spectrum are
base-load technologies such as coal-ired power and nuclear power. hese
technologies cannot respond quickly to increased demand need, nor can
they power down quickly. herefore, they are most economically utilized to
provide ixed power output—base-load. At the other end of the spectrum
are peak-load technologies such as natural gas and hydropower. Both of
these electricity generation technologies can adjust to demand luctuations
within minutes (for gas) or seconds (for hydropower). Wind power is most
efectively used as a base-load technology because it allows the turbines to
function at maximum capacity.
2.3.2 Stochastic Flows
With that said, the act of generating electricity from wind does create some
arduous supply management challenges stemming from the stochastic
nature of wind. he amount of energy generated from a wind turbine can
vary signiicantly from minute to minute, hour to hour, day to day, week to
week and year to year. However, as this section will demonstrate, insinua-
tions that signiicant contributions from wind power will unfailingly desta-
bilize electricity grids are largely exaggerated, because there are operational
strategies and technological ixes that can be adopted to minimize the
severity of the problem.
Strategic site planning, geographic dispersal of wind power facilities, and
technical decisions made when selecting turbines (i.e., adjustable rotors,
