wind energy at home

[McPatrick]

I was wondering if any one here has one of those small wind turbines that are meant to be used around the house. What do you power with it and how efficient is it?

[trebuchet03]

Not enough wind here And the property manager wouldn't approve :/

[ajohnmeyer]

are you talking about the really small ~3' diameter ones? Or the bigger ~12' ones like a skystream?

The smaller 3' turbines look almost useless. There's no way to extract a usable amount of energy from such a small swept area, plus most installations I've seen have been 6-10' above a roof. Not good.

A turbine is supposed to be at least 30' above any obstacles within a 100' diameter, plus the energy output is increased with height. (twice the height, twice the energy, generally)

For residential use I just don't see the benifit of a turbine with a swept area of less than 10' It just costs too much (time and money) to put up such a small system, the payback time would be way too long.

[skewbe]

Still, might be worth the exercise acedemically speaking. If you can get a working model built out of relatively cheap stuff that has ANY return, it may motivate you to bigger and better things.

[ajohnmeyer]

I can understand wanting to do an "academic excersise" but there are ways to do a 10' or bigger turbine that don't have to cost much. The particular example I'm thinking of are the 8-11' turbines that can be made from a Volvo steering knuckle, hub and brake disc.

[QDM]

I use solar at my house because there is no wind. A guy I know uses one of those little 3' turbines to power the lights at his hanger on the Oregon coast, works fine. Another friend of mine has 2 of those 3' turbines on his 2nd home in the Oregon desert. Works great for him.

Q

[trebuchet03]

The wind turbines on sailboats have a very small size.... But the sound of them in even moderate wind is unmistakable

I think this is a case of a choosing the middle ground of all or nothing... Especially if you're building yourself... I'm likely not the only one that has taken on an overambitious project (perhaps due to scale ) and has since put the project on indefinite hold (my proud words of admitting failure )....

[ajohnmeyer]

I guess my main objection to the small turbines is that there are much better options for the price. Take the few hundred bucks that you would spend for the turbine and spend it on a solar (PV) panel or two. Output isn't dependent on wind, zoning restrictions are much easier to get around, and it won't require any maintenance.

[skewbe]

Couple hundred? Maybe. Ought to be able to scavange most of it though induction grid tie motor off the curb, hand carve some wood blades, rig up a gear ratio from bike parts or so.

Is there a way to have a "squirrel cage" or paddle wheel type windmill, that sits by the roofline and lets the roof slope "funnel" the prevailing winds to it? Think anerometer, with troughs instead of cups, and they scoop air by the roofline.

Treb, does your fancy program have a roofline model handy to identify the optimal positioning for such a system? I think zoning can be a big concern actually, and such a system would be somewhat low profile, if it even works.

[trebuchet03]

Originally Posted by skewbe

Treb, does your fancy program have a roofline model handy to identify the optimal positioning for such a system? I think zoning can be a big concern actually, and such a system would be somewhat low profile, if it even works.

I don't think it can optimize, but I think it can batch run several setups.... I've been having a problem with it though -- I tried running a model of a semi truck, and I ran out of memory (filled up to max paged and physical) before finishing the first (of several hundred) iterations.... I need to find a bit more computing power to run larger objects...

I know code for South Florida has some specifications for roof angle (and I think angles for specific directions) - for hurricane force wind purposes That's why we don't have high pitched roof lines... Not sure if that helps answer your question at all.