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Bzzzzzt
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# Posted: 8 Feb 2015 10:37pm
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Thought someone here might find this useful. I may try this myself. My only question is how to keep the wires from wrapping around the pole when the wind changes direction and swings the wind generator around and around.
http://www.motherearthnews.com/renewable-energy/homemade-wind-generator-zbcz1407.aspx #axzz36yyyMynI
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toyota_mdt_tech
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# Posted: 8 Feb 2015 10:57pm - Edited by: toyota_mdt_tech
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That has to be almost a hoax. That is a Delco Remy 12SI alternator. Smallest rated version was 56 amps (7271 Lester= 56 amps, 7272 is a 66 amps, 7273 is a 78 amps and 7294 is a 94 ampere, they are calling it a 7127 which is a 10SI, but it has the 12SI turbo fan,, 7127 is rated for 63 amps) and it is using a clutch fan (viscous coupling) which couples as it sees heat from the radiator. Not present, means it would freewheel all of the time. That alternator would make a semi modestly tight belt slip on a V8 slip, I have no idea how wind via a viscous coupling would make it work. Unless you removed the internal voltage regulator and ran a variable resistor inline to the field current (rotor) and turned it way down and did away with the fan clutch.
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MtnDon
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# Posted: 9 Feb 2015 12:38am
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I don't believe it. For a few reasons.
The fan clutch toyota_mdt_tech mentioned is a biggie. As he mentioned those clutches are made to permit the fan to more or less freewheel at cold and normal temperatures. They "tighten up" at elevated engine coolant temperatures.
Another question is the diameter of the fan is almost nothing when compared to the blade diameters used on wind generators that are based on automotive alternators. http://www.windbluepower.com/category_s/35.htm
And third, an non modified alternator needs battery power to excite the coils for the magnets. That is inefficient. Have a look at that windblue page and you will see they replace the electromagnet coils in the alternator with a special permanent magnet rotor. In a car with a gasoline engine spinning the alternator it doesn't matter that the alternator uses electricity to make more electricity. Dealing with off grid and finicky winds that could end up being a net discharge for the day.
And fourth, the author does not get into explaining the special needs of the charge controller used with a wind generator. Wind generators need a place to dump excess current or they need a brake. Again, refer to the windblue page and read their controller page. They don't go into detail but they make mention of that.
IMO, Motherearthnews just went down a few notches on the believability scale.
Fifth.... the alternator is open to the weather. Under the hood the alternator is basically dry or warm enough to evaporate any water that gets in there. Out in the wind and rain it's another story. Bearings will rust.... Wildblue replaces them with sealed bearings. Note the prices on their alternators.
Homepower magazine did an article on auto alternators as wind generators many years ago. Their conclusion was they are lousy at the task and more trouble than they are worth. Or something like that.
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Julie2Oregon
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# Posted: 9 Feb 2015 04:39am
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I saw this on Mother Earth several months ago and my first reaction -- without any mechanical knowledge -- was "pull the other one!"  For the sheer (get it?) fact that engineered small turbines require some sophistication to produce a scant amount of power from sustained winds at low speeds and also need mechanisms to shut the things down at high speeds. In other words, it's difficult to get a usable amount of wattage from small turbines, even for the professionals!
They do produce AC watts, though. I'm considering buying one to assist with battery charging, especially in the winter when the days tend to be cloudier but windier. If it does turn out to produce more watts than expected, I could use it to power some small things in a pinch.
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BaconCreek
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# Posted: 9 Feb 2015 07:28pm
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I have been subscribing to Mother Earth News for several years now and I am seriously considering dropping it due to articles such as the one you referenced. Also the magazine seems to have an increasingly preachy/lefty bias.
Many of their ideas are worth considering but just as many are pie in the sky and unrealistic.
I am thinking Backwoods Home has more relevant information without all the hippie crap. 
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toyota_mdt_tech
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# Posted: 9 Feb 2015 09:29pm
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Quoting: BaconCreek "increasingly preachy/lefty bias". "without all the hippie crap".
Right on Bacon Creek. I bet we would get along real well. 
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