Environmental Engineering Reference
In-Depth Information
per second (force 4-5 on the Beaufort scale), and cut off at winds above 25 metres per
second (force 10 or higher) to prevent damage to the turbine. The largest turbines begin
to generate electricity at wind speeds above 5 metres per second, operate best at speeds of
7-15 metres per second, and cut off at speeds above 25 metres per second.
Figure 4.14.
A technician controls the installation of the generator in the nacelle of a
wind turbine. After this, the rotor will be assembled. The holes in the hub section indicate
where the blades will be attached.
Source:
Paul Anderson at Wikimedia Commons.
Most medium-sized and large turbines feed the electricity they generate directly into
the power grid. This is because wind, like solar power, is highly intermittent, and at any
given time a turbine is likely to produce either too much or too little power for any single
household, farm, or factory. Economy of scale is also an important factor in wind energy.
A single turbine requires less space, blocks the flight path of fewer birds, and is more
economical to install and maintain than numerous smaller turbines. That is why we are
likely to see the trend towards larger, more powerful turbines continue. Whereas in 2005
the average output of turbines installed in commercial wind parks was 700 kilowatts, by
