Wind power turbines

[Coldicote]

A big new turbine has just appeared on the Sussex Downs to serve Glyndebourne Opera House. This makes me curious about small turbines for private gardens or roof tops. There are references on the internet but answers to obvious questions are not easy to find. Are they useful for anything other than lighting? Do they have battery power storage for times when there is no wind to operate them? With the ever increasing cost of commercial power, alternatives are becoming more interesting. Does anyone have knowledge or experience please?

[pink-kittens]

I think they store electricity don't they?
Anyway, this should help

http://www.northampto...ntID=585&pageNumber=1

[Old_Geezer]

Am I the only one who would not be happy if my neighbour fitted one on our roof ? Even if totally silent, I'd not want something whirring above me like that waiting to break and come through.

[Coldicote]

Thank you pink-k, and Old G I think I agree with you. It would be interesting to hear from someone who actually has one

[beso]

In suburban locations, the wind speed is too low and the turbulence is too high for turbines to be cost effective.

There are several designs that claim to be optimised for low speed operation but the fact is that there is very little energy in low wind speeds and no matter what the design it is quite impossible to extract more energy than is actually in the wind.

Moreover it is actually impossible to extract more than 59% of the energy in the wind because it needs some energy to keep moving and come out the other side of the turbine. I have seen claims by manufacturers that show their turbine exceeding this figure, meanng that it is obviously a false claim.

These designs are often include "features" that are supposed to enhance perfomance in turbulence and low wind. In fact the "features" are invariablly associated with low performance efficiency.

Two that particularly come to mind. A spiral vertical axis machine from Europe that is incredibly expensive. The other is built in the US. It has the generator around the outside of the turbine and the most unlikely blade profiles I have every seen in a wnd turbine. This machine is one that publishes impossible performance figures.

BTW I used to work in the industry on design of small wind turbines.

[Coldicote]

Thank you Beso, a very informative contribution.