|
You can only
produce useful energy from wind if the wind is strong and
constant. Despite the average UK figures of around 4m/s
wind speed this is in clear air some distance above the tops
of our roofs. As air travels around local obstacles, such as
your house, your chimney or the trees in your garden, then
it slows and rolls over. It becomes gusty, turbulent and
unpredictable. This is not 'clean air' and such disrupted
airflow can actually damage a wind-turbine. At the very
least it will have little useful energy to extract. As the
wind will seem to be blowing in all directions at once then
the turbine is unable to find the direction to point into.
In short - useless.
So we have established
that you need to mount your wind turbine well away from
buildings and other tall obstructions. That is a minimum of
11 meters above an obstacle within 100 meters. However, even
in built up areas in the UK you are unlikely to experience
much beyond 4 meters/second wind velocity. As mentioned
above you would have to have turbine blades of 4m diameter
to start generating serious juice. Hence the domestic
wind-turbine is more likely to be some useless white
elephant or annoying piece of street architecture than
anything useful.
Of course all of
this is excellent bad publicity for those who are opposed to
wind-turbines. And this is a big worry. Domestic
wind-turbines could be a significant propaganda victory for
the NIMBY-brigade and pro-nuclear lobby. It doesn't have to
be that way. Let us be very clear. Small (note small)
wind turbines can generate most of our energy needs. Forget
the monster wind-turbines in the monster farms off-shore.
They are good but they are BIG because that is the most
efficient model for return on investment. However, if you
were to use the same area with lot of smaller wind turbines
you will actually generate MORE power. The only reason we
see the monsters is because that gives better pay-back to
the investor.
When we say
"small" we do not mean domestic roof mounted units. They
have to be at least 4m in diameter and mounted far away from
obstructions as mentioned above. Hence we need to be
imaginative. Such a turbine will be to expensive for one
person but a community could raise the funds for this. Many
Business's and Factories have large car parks in which
turbines can be mounted. There is plenty of empty space
around our motorways, farms, school-playing fields, village
greens and rural community halls. In short the micro-turbine
will be a community and small business venture. Today small
villages across Britain are looking into mounting several
small turbines outside their villages to generate a large
part of the villages electrical load. This is the way ahead.
So get together
with your friends, your neighbours and your community and
invest in a cooperative approach to micro-generation.
Windpower is the future and by far the cheapest way to stop
emitting carbon and to generate power without wasting
valuable fossil fuels. Wind is essentially infinite. It is
formed by the power of the sun unevenly heating our
atmosphere. It is another form of solar power but one that
is a hundred times cheaper than Photovoltaics - if somewhat
less practical on your roof. |
