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Pete Dorr
11-04-2008, 01:39 PM
Any recommendations on a wind meter I can collect data from so I can do some analysis to see if any of the small sized wind turbines (http://news.cnet.com/8301-11128_3-10075828-54.html?tag=mncol;title) would be feasible at my house.

Thanks
Pete

Popeye
11-04-2008, 01:47 PM
http://scientificsonline.com/images/250/30/30536-33.eps.jpg

switters
11-04-2008, 02:33 PM
the term is anemometer, and your best bet is to rent one because you have to have it at the height the turbine will be. Typically the wind power supplier in your area will provide one because they like to do a survey to make sure you have the right area.

Home power magazine article link, http://www.homepower.com/article/?file=HP115_pg76_Woofenden

about siting your wind power.

Good luck

Milo Christensen
11-04-2008, 02:33 PM
You're dreamin' if you think that wind turbines will ever be allowed on Cape God!

Pete Dorr
11-04-2008, 02:41 PM
You're dreamin' if you think that wind turbines will ever be allowed on Cape God!

Milo

I'm nowhere near the K compound :D

No tower - I believe the town regs say the tower needs to fall on your land if it falls over. That kills towers for about 98% of the properties.

My gut feel is that the small scale turbines would work well if you had clean wind. I won't really have clean wind. But I'd like to know.

Pete

Milo Christensen
11-04-2008, 02:44 PM
I just couldn't resist. I'm sorry. It would seem that that kind of data has already been collected. But without a tower, you're going to lose so much velocity that I suppose you'll have to measure it.

ahp
11-04-2008, 04:59 PM
My Dad told me, and he was in the windmill business many years ago, that it needs to be at least 20 feet above any nearby obstructions. No doubt there is better criteria available today.

Chip-skiff
11-04-2008, 05:09 PM
Websites that sell turbines (e.g. Real Goods, Southwest Windpower) often have recording anemometers suitable for your use, but they tend to be $600 or more. Best is a system that records wind velocity and direction, with a data output that can be loaded to a PC for analysis.

You don't necessarily need to mount the instrument at the same height as your intended turbine. There are coefficients for wind speed at various heights. The major complication is turbulence generated by structures, trees, etc. on the track of the prevailing wind. For generating power, the best winds are steady, laminar (smoothly layered), and consistent in direction.

We have lots of wind here (SE Wyoming) but the narrow mountain valley where I live also has extreme velocity shifts, wind shear, and 180° direction changes that tend to burn out the bearings on small wind turbines. So, despite the abundance of wind, we installed a solar PV array.

(Treat it as a pleasurable challenge, like shaking out the problems with a new rig.)

rbgarr
11-04-2008, 05:13 PM
It's my understanding that consistent 8-10 knots of breeze (pretty much around the clock) is needed to really make them worthwhile. That's a lot of steady wind IMO and I doubt you get that much even on Buzzards Bay.

JimM
11-04-2008, 06:51 PM
The taller your tower the better chance you have the clean wind you want. Figure out what is the larges tower you can put on your land and still meet the regulations. Measure the wind at that hight.

Bob Cleek
11-04-2008, 08:20 PM
Google up the US Dept of Commerce weather department or your local agricultural extension office. There is weather data for the whole country going back eons. Somebody there will be able to tell you the average wind speed and direction for your location. Shouldn't be a problem. I'd expect any of the sales outfits that provide the equipment will be able to tell you this, too. Wind, though? You'd have to have a lot of wind and a lot of propellers to really get anything worth the expense, I'd expect. Have you considered solar? Costs more, maybe more than you save, but it you are a "green" nut, it may be a better option.

Woxbox
11-04-2008, 11:18 PM
Somebody there will be able to tell you the average wind speed and direction for your location.


But the average speed isn't helpful. What you need to know is how much time the wind is in the effective range of the generator.

They put a big experimental windmill up in the Poconos back in the 80s. The Weather Service said the average wind speed at the site was, if I recall right, 15 mph. After a few years of unsuccessfully trying to get power out of the windmill, they found that the average was 15 mph -- but almost always too high or too low for the mill to work.

Chip-skiff
11-05-2008, 01:58 AM
There's quite a lot of useful information on the Southwest Windpower website, including a good download on siting:

http://www.windenergy.com/index_wind.htm

There are also windpower maps— judging from which you're in a good spot. Assuming the wind doesn't abruptly cease at the shoreline.

http://farm4.static.flickr.com/3059/3004976664_356fd326c4.jpg?v=0

huisjen
11-05-2008, 07:54 AM
What I've heard is that a good anemometer costs about $500, and a small turbine costs about $1000. The anemometer has a resale value of about 37 cents, while the used turbine holds it's value fairly well. Likewise, if you're going to need a tower to support a small turbine, go ahead and get one that strong, rather than throw money away on the lighter weight anemometer tower. You should be able to monitor energy output from the turbine just about as easily as wind speed from the anemometer. Later, if you decide it's worth it, you get a larger turbine, possibly upgrading the tower (if necessary) and selling the old tower with the old turbine.

Dan