Home built 500 watt wind generator for $350 design by Hugh Piggott

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Has anybody built or know anybody who has actually built the brake drum wind generator that Hugh Piggott designed and shows how to build in his book? It uses a ford F250 brake drum as the main thrust and rotational bearing with the generator inside the brake drum.
Its an auto-furling 3 bladed design that he claims that can be home built for about $350 US and will provide 500 watts of power at the rated wind speed of about 25 MPH
I'd like to know how it actually performs before I spend the 25 bucks for the book, according to the description it looks super sturdy and I think I can scale it up to meet my needs (1.5 KW), picoturbine.com says its a great book and the generator can be easily built but I'd like to have some unbiased opinions before I buy, after all they're trying to sell the book and would naturally play it up.

Thanks!

Dave

-- Dave (AK) (daveh@ecosse.net), July 10, 2000

Answers

Dave, I know enough to know that Hugh Piggott is an actual doer, not just somebody assembling stuff from other books and hoping to pass it off as their own work. I've come across posts on other boards by Piggott, and he explains things clearly. So I'm guessing his books would also be clear. I'm not sure if it was picoturbine or not, but I did stumble across someone selling an "Americanized" version of his books. Don't know just how important that would be. What I'd suggest is asking your library to bring in a copy via interlibrary loan. Amazing what you can get. Pay attention to whether it is the British or American version and if you like it, buy it. Interlibrary loan has saved me a bunch of money over the years. Books that other people have said I really needed to buy have disappointed me, other books that I didn't expect much from turned out to be great and I went on to purchase my own copy. Gerbil

-- Gerbil (ima_gerbil@hotmail.com), July 10, 2000.

Even if you built his machine and it runs at 100% efficiency - 500 watts at the wind speed of 25 mph - what do you have? Enough power to light a couple of light bulbs. Check with your local weather service to determine what is the average wind speed in your area. Likely it is far, far less than 25 mph. That's a pretty good breeze - about enough to blow your hat off. It really doesn't matter how efficient or large the generator is if you don't have the average wind speed to support it.

-- Ken Scharabok (scharabo@aol.com), July 10, 2000.

I checked the wind power maps and my area is a cat2 in summer and a cat 3 in the winter, I realize that Im not going to get 500 watts on the average, which is why I'd have to scale it up. I think (hope actually) I can put two PM alternators attached to a six-blade turbine for a nominal 1 KW and have two of those up on the tower for a total of 2 KW nominal and around 1 to 1.5 KW average. I know I can put up a guyed lattice tilt-up tower to support it without too much trouble, thats pretty much just straightforward welding work.

I'd love to get my hands on a design for a homebrew 2 KW with just one set of blades, but I just cant find even a hint of anything like that and I dont have anywhere near the knowledge to design it.

Thanks

-- Dave (AK) (daveh@ecosse.net), July 10, 2000.


Dave: Dunno if you've checked out homepower.com yet or not but all their back issues are available online, free. They have a search engine and an extensive index too. I've read numerous mentions of Piggot there so maybe it would help.

-- john leake (natlivent@pcpros.net), July 10, 2000.

Concerning HomePower magazine...

Spend the money and get their CDROM of the past issues. If it's been wrenched, it'll be there. A great and _cheap_ resource.

J

-- j (jw_hsv@yahoo.com), July 11, 2000.



In addition to checking at Homepower, you might look at ebay(everything else solar energy) there often are Air 403 wind gennies for about $400. They are 400 watts at 28mph, 600 at 38mph and have a built in regulator. I have the older model Air 303 (300 watts) and am very satisfied with it.

-- Don Atkinson (jatkinso@whidbey.net), July 15, 2000.

Here is an alternative. This wind turbine can be built for $50 plus three 55 gallon drums, produces 2500 watts at 30 mph wind speed and is virtually impossible to overspeed. For pictures, email smithja@sisna.com

-- Paul Clint (smithja@sisna.com), April 03, 2001.

Be aware that wind power works by order-N-cubed, so double the wind speed results in eight times the power, and half the wind speed (12.5 MPH) means 1/8 the power, i.e. about 57 watts. Your wind speeds will likely fall on something like a bell curve, which by its spread will tell you much more about the power you can expect to get than a simple mean speed would. For example, if the average wind speed is 15 MPH but this is comprised of short blows in the vicinity of 30 MPH, this is both good news and bad news: it means that you will get more power on average than if the wind blew at a steady 15 PMH, but that you're going to have to do some storing for the lulls. Wind and solar tend to complement each other (overcast often implies windy) so getting some of each may be better than relying on lots of one.

-- Leon Brooks (greenspun@leon.brooks.fdns.net), May 22, 2001.

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