Why big wind's flying, but home turbines have hit a stormy patch

I've written a piece about wind power in today's Guardian. Just in case the article's taken the wrong way, I'd like to stress that I'm hugely in favour of wind power, but from what I've heard and read, home turbines just aren't yet ready for primetime - and pretending they are could have disastrous consequences. Have any thegreenguy readers got a home turbine? If so, I'd love to hear about your experience of it. I would pledge this is my last Xmas post, but I've clearly broken my promise on that already. Photo: Stuart Yeates

Comments

[andrew]

hello

intriguing article on turbines and something we at www.suma.co.uk have been struggling with for some time, we try to operate our business in as ethically and sustainably a way as possible and would dearly love to be able to generate our own electricity and you would think that being at the foot of the pennines that we would be scoured by the chill northern blast however we are at the base of our valley and a turbine is not an option, we have long been told that many of the commercially available turbines are entirely unsuitable for a business of our size consuming the (frightening) amount of power we do, Ecotricity unfortunately were 28% more expensive than Scottish power and even though we are an ethical business, we are still support our efforts by being a viable business and unfortunately 28% represents an extra £3500 per annumm on our current charges through Scottish Power.

i like the blog by the way, do you get you wholesale food delivery from our good friends at Essential Trading in Bristol, if we are talking about down shifting and money saving then your readers ought to know that buying direct from wholesalers saves you around 32.5% on retail price

toodle-oo

mac

[Philip Goatly]

I note that before Christmas you commented on the poor performance of
small wind turbines, particularly those in an urban environment. Far from just
practical issues, there are theoretical reasons why such turbines may only
produce small amounts of electricity.

The amount of energy that the wind can provide is proportional to the cube
of the wind speed.

Most of these turbines have a maximum electricity production at about 12
metres/second. In my area of the country, at a height of 10 metres, the
average windspeed is 5 metres/second. Since 12 cubed = 1728 and 5 cubed =
125. A wind turbine rated at 1KW at 12 metres/second should produce
125/1728 * 1 KW at 5 metres/second.

This works out at 72.3 watts.

Another factor involved in the amount of power produced by the wind is the
'area' of the wind captured. This depends on the size of the blades on the
turbine. It varies as the square of the 'radius' of the blades.If you
double the length you get 4 times as much power.

It would therefore appear that large turbines, in windy places, are the
best bet.

Cheers, Phil