Will Windmill on your House Save You Money
Wind energy is a tried and tested technology that has
been used for centuries. More recently it has become a popular way to
generate electricity, as concern has grown about man-made Climate
Change. Electricity generated from the wind does not produce any carbon
dioxide, and has none of the worries associated with nuclear power. As a
result, many have come to see it as a major part of the solution for
man-made Climate Change. If we could generate a substantial portion of
our electricity from wind, we would massively reduce the amount of
carbon dioxide that we emit into the atmosphere. Furthermore, the cost
of generating electricity from large wind turbines is falling, and is
expected soon to be cost competitive with electricity generation from
fossil fuels.
As a result of this, wind farms have sprung up all over the place, with
enormous turbines that each generate enough electricity to power
thousands of homes. Some people have also tried to replicate this
technology on a small scale, by installing a small wind turbine on their
house. Most famously in the UK, David Cameron, the leader of the
Conservative Party, had a small wind turbine installed on the roof of
his London home.
However, for most households, especially in cities, wind turbines are an
expensive way to achieve very little. In fact they are almost useless.
It has been calculated that a 1.75 meter diameter wind turbine, in an
area with UK average wind speed of 4 meters a second, will produce under
5% of an average UK household's annual electricity consumption. And this
assumes that the turbine is working efficiently.
However in cities, the buildings cause a great deal of wind turbulence,
and slow down wind speeds. Therefore to make a turbine work efficiently
it would need to be fixed far above a house (up to 10 meters). Fixing a
windmill on a long pole like this would likely cause serious damage to
your house, as would trying to go for a bigger turbine to generate a
larger proportion of your electricity.
The only case when you should consider a wind turbine is when you can
site it far enough from any obstacles like buildings, and in a
relatively windy site. Some people who live in the country are able to
set up turbines that generate a significant proportion of their own
electricity.
However, the vast majority of people live in cities, where small wind
turbines are next to useless. So what should you do instead? The first
thing you should focus on is using energy much more efficiently, by
insulating your home to save heat, installing a super-efficient
condensing boiler, buying energy-efficient appliances like fridges and
washing machines, and installing low energy light bulbs.
Once you have taken these basic measures, you can start to think about
generating your own energy using other 'clean' technologies. The most
cost effective of these is generally solar hot water, where solar panels
on your roof provide up to 70% of your annual hot water needs by using
the sun's heat. You can also consider using a ground source heat pump to
heat your home, and solar PV panels on your roof to generate
electricity, but these measures can be expensive, and so will not be for
everyone. More details of all these technologies are available on
downwithco2.co.uk.
Unfortunately small wind turbines in their current design are not the
way forward for the vast majority of us. It is possible that in the
future someone will come up with a better design that can work in
cities, but until then we will have to carry on building the larger
versions, and take other actions to reduce our home's contribution to
Climate Change.
About the author
Alex Perry is a founder of DownwithCO2.co.uk, which helps people save energy, save money and reduce CO2 through providing information and contacts