This seems to worry supporters of Wind Energy's Absurd (or at lease they like
to tell other people that they should worry about it).
|Wattle Point Wind Farm, Yorke Peninsula, South Australia
|So far as I know, no turbine blade, or blade section, has
ever fallen in Australia
Wind turbine blades have been known to fail and break apart.
This can result in pieces flying several hundred metres when the failure
was caused by the turbine rotating at very high speed when its control
mechanisms failed during a high wind.
The break-up of a rotating turbine is an extremely rare event.
It has never happened in Australia (as of January 2017).
An anti-wind power Net site (Caithness Windfarm Information Forum)
in 2013 recorded an average of about 20 blade-failure events per year
world-wide (not necessarily in utility scale wind turbines and the blades
did not necessarily fall off).
At the time there were several hundred thousand utility scale wind turbines in
Assuming that all 20 blade failure events recorded by Caithness were in
utility scale turbines, and assuming 250,000 turbines total we can calculate a
probability of one turbine in
12 000 suffering from blade failure in any one year.
That is, a probability of blade failure in a particular turbine of 0.00008 in
any one year, or 0.0000002 on any particular day.
While it seems that no one has yet been injured by a blade or piece of a
blade thrown from a utility-scale wind turbine, considering that there are
several hundred thousand utility scale wind turbines in the world it is
quite probable that it will happen some time.
Compare this theoretical danger, someone might die sometime, with the very
real risk posed by the burning of coal.
In fact, wind turbines save lives by
replacing coal fired power stations.
Follow the link to read a World Health Organisation publication that
puts the number of deaths from air pollution at seven million per year; much
of this pollution is due to burning coal.
The image of a wind turbine blade falling off and killing someone is easy to
imagine and might be frightening.
This type of scaremongering, while making no attempt to place the risk in
any sort of perspective, is common among those who are trying to get a
message across without any concern for the truth.
A book I can recommend on this sort of psychological trickery is The Science
of Fear: How the Culture of Fear Manipulates Your Brain, by Daniel Gardner.