My Home-Built Wind Turbine FAQ
Please read this before emailing me with questions

 

Q. Can you please help me with my school or science fair project?

Q. Why haven't you answered my question? I've emailed you X number of times and you still haven't responded!

Q. Can I just plug my solar panel into my house wiring to help offset my electric bill?

Q. Can you help me modify your charge controller design for my system which runs at something other than 12V?

Q. Where in Arizona is your property located?

Q. Why can't I just use a car alternator in my wind turbine?

Q. How is the hub attached to the motor shaft?

Q. Will I be able to heat my house with a wind turbine like this?

Q. How do you prevent the wire from twisting up inside the mast?

Q. Do you have any blueprints, schematics, instructions, parts lists or plans you can send me?

Q. How noisy is your wind turbine? I'd like to build one, but I'm afraid it might be too loud.

Q. Do I really need the battery bank and charge controller? Can't I just connect my inverter or other appliance directly to the wind turbine?

Q. Do I really need the charge controller? Can't I just connect the wind turbine directly to my battery?

Q. A saw this motor on Ebay, item number xxxxxxxxxx. Will it make a good generator for a wind turbine?

Q. Can I use an AC motor as a generator on my wind turbine?

Q. Can I use car batteries for my battery bank? Why do I need special batteries?

Q. Why do you use 3 blades wouldn't 2, 4, 5, or n number of blades work better? Do you think my wind turbine design with n number of blades will work?

Q. I understand the mechanical aspects of your wind turbine, but electronics part is all Greek to me. Can you teach me enough electronics to understand this system?

Q. Can you design a wind turbine/battery/charge controller system for me that will power my home/farm/studio/cabin/office/barn so I can get out from under the thumb of my evil electric company?

Q. Do you have a printed circuit board or board layout for the charge controller?

Q. I tried building a charge controller using your schematic and instructions, but I can't get it to work. Can you help me troubleshoot and/or repair it?

Q. Can you build a charge controller for me?

Q. Can you sell me a wind turbine?

Q. Will a solar panel charge controller work for my wind turbine?

Q. Do you sell your excess power back to the electric company? Can I do it?

Q. Which direction does your wind turbine spin?

Q. How many birds has your wind turbine killed?

Q. Can you please help me with my school or science fair project?

A. I get this request several times every day. I'd really live to help. I'm sorry, but there just isn't enough of me to go around to fulfill all the requests for help I get.

 

Q. Why haven't you answered my question? I've emailed you X number of times and you still haven't responded!

A. I get a LOT of questions from people. I can't possibly answer them all. I can barely read them all. A lot of questions are repetitive. I get tired of answering the same questions over and over again, which is why I created this FAQ, and attempt to keep it updated. Questions covered in the FAQ almost certainly will not be answered. Also, people tying to emulate my work should have at least a basic grasp of electronics and mechanics, since I don't have the time or inclination to teach basic electronics or mechanics theory to them all individually. So if a question shows a level of ignorance about electronics or mechanics that is going to require a long and complex explanation and/or tutorial, then you are simply out of luck. I just don't have the time to help you out. Sorry. Remember though, Google is always out there, ready and willing to answer all your queries if I can't.

 

Q. Can I just plug my wind turbine into my house wiring to help offset my electric bill?

A. No! No!! No!!! I am getting this question a lot and it really scares me. You need specialized equipment like synchronous inverters and transfer switches, and a licensed electrician, to interface a wind or solar system with your house wiring safely and legally. Do not attempt to do it yourself unless you really know what you are doing and have obtained all the necessary equipment and permits. In some areas some or all of the work may have to be done by a licensed electrician. Check your local codes.

 

Q. Can you help me modify your charge controller design for my system which runs at something other than 12V?

A. I get this request fairly often. People have solar and wind systems running from 6V-60V. I settled on 12V for my system, and it works for me. I really don't have the time to work on modifications that I won't be able to use. I will say this though, the charge controller should In Theory work from 12V, up to 36V by only replacing the relay with one that has the correct coil voltage, and re-calibrating for your high and low voltage points. I haven't tried this though, so there may be some hidden gotchas. Operation below 12V, or above 36V would require a major redesign of the charge controller.

 

Q. Where in Arizona is your property located?

A. If you were to draw a line on a map of Arizona between the towns of Snowflake and St. Johns, my property would be close to the midpoint of the line. The nearest town is Concho. I'm not going to be more specific than that in order to preserve my privacy.

 

Q. Why can't I just use a car alternator in my wind turbine?

A. Car alternators are designed to work at much higher RPMs than is typically produced by a wind turbine. If you can stand the power losses and added complexity, it may be possible to use belts or gears to increase the speed of the turbine to something more like what an alternator needs. There are also permanent magnet alternators available designed especially for wind turbine use, but they tend to be quite expensive.

 

Q. How is the hub attached to the motor shaft?

A. The hub has 2 set screws that tighten against the motor shaft and hold it in place.

 

Q. Will I be able to heat my house with a wind turbine like this?

A. Probably not. This wind turbine only produces a few hundred Watts peak. It probably wouldn't even do a very good job of heating one room, let alone a whole house.

 

Q. How do you prevent the wire from twisting up inside the mast?

A. I don't do anything to prevent the cable from twisting. Twisting hasn't proven to be a big problem. In my area, the wind blows primarily from the South and West. The wind turbine spends most of its time slewing back and forth between these two directions, covering only 1/4 of a circle. It hardly ever swivels all the way around. And it seems to be just as likely to go around one way as the other. So there is no big tendency for the cable to twist up. If it ever does become twisted, I can always disconnect the wires at the bottom of the mast and manually untwist them. I generally only use the turbine for a week or two at a time. If I used it for longer periods, I might start seeing a twisting problem and work up a solution for it. Slip rings are a possibility. There are several amateur-built slip ring designs on the internet. Google for them.


Update: Here is a video explaining the wire twisting issue.

 

Q. Do you have any blueprints, schematics, instructions, parts lists or plans you can send me?

A. No. All the information I have related to this project is right there on the web site. Read it thoroughly and follow the links provided. I realize not everyone will be able to build their own wind turbine with only the information provided. Many people seem to want step by step instructions. I don't feel that step by step instructions are useful with a project built using found materials and improvised structures. Trying to exactly duplicate my wind turbine may be unnecessarily difficult. You may not be able to get exactly the same parts I used. Instead, I recommend you use my ideas as a starting point, then innovate using the materials available to you. If you are still stumped, I can only suggest you seek help locally from handy people you know, and research any aspects of the project you don't understand.

 

Q. How noisy is your wind turbine? I'd like to build one, but I'm afraid it might be too loud.

A. The wind turbine is not really very noisy. I do have it set up about 100 feet away from me, but it is not terribly noisy even up close. It isn't much noisier than the wind itself. Most of the time, in a stiff wind, I can't really hear the wind turbine at all over the roar of the wind through the trees. The only time I actually notice the noise from the wind turbine is when the wind has been blowing hard and then suddenly drops off to almost nothing. Then I hear the whooshing of the turbine blades for a few seconds until they slow down.


Update: Here is a video of the wind turbine in operation.

 

Q. Do I really need the battery bank and charge controller? Can't I just connect my inverter or other appliance directly to the wind turbine?

A. The Voltage output from the wind turbine varies wildly with wind speed. You would be very liable to damage the inverter or other appliance by running it connected directly to the wind turbine without a battery bank and charge controller in the system. The load from the battery bank smoothes out the Voltage to something the inverter can handle, and provides power during periods of little or no wind.

 

Q. Do I really need the charge controller? Can't I just connect the wind turbine directly to my battery?

A. The purpose of the charge controller is to prevent destruction of your expensive batteries due to over-charging or over-discharge. You can go without one, but you would have to slavishly watch the voltage on your batteries and connect and disconnect them from the wind turbine manually. Fall asleep at the switch just once and you will have either over-charged or over-discharged batteries that may be irrecoverably dead.

 

Q. A saw this motor on Ebay, item number xxxxxxxxxx. Will it make a good generator for a wind turbine?

A. Maybe. I get this question A LOT! I don't have the time to research every request that comes in. So don't be offended if you do not get an answer. Here is the best advice I have. You want a permanent magnet motor that is rated for high voltage, but low RPMs. That's kind of an odd combination. The vast majority of the motors on Ebay don't make good generators. Every once in a while though, a good one crops up. Watch for old tape drive motors, electric lawn mower motors, floor buffer motors, and servo motors. Even within these categories though, most of the motors won't be very good generators, but you are more likely to find one that is than in other categories. Hopefully the photos or description of the motor will include the data plate information. Go to the manufacturer's web site and research the motor's specs. Ask the seller if he has tested the motor as a generator, or if he can test it for you. If a motor of possible use as a generator is selling cheap, you can always buy it and test it yourself by chucking it into your drill press or lathe and turning it while attached to a load. If it is a good generator, great! If not resell it on Ebay and get your money back.

 

Q. Can I use an AC motor as a generator on my wind turbine?

A. Probably not. I have heard of people using AC motors as generators by relying on residual magnetism in the motor and the dynamo effect, but it doesn't really seem to work very well, if at all, in most cases.

 

Q. Can I use car batteries for my battery bank? Why do I need special batteries?

A. Car batteries are not a good choice for a wind or solar power installation. They are damaged if they discharge too deeply. Car batteries are designed to deliver a quick burst of power to start the engine. They are not meant to be deeply discharged and recharged repeatedly. This will quickly destroy them. Deep cycle batteries work much better in this application.

 

Q. Why do you use 3 blades wouldn't 2, 4, 5, or n number of blades work better? Do you think my wind turbine design with n number of blades will work?

A. My early research showed that 3 is about the optimum number of blades. Most commercially made wind turbines have 3 blades. From what I understand, turbines with even numbers of blades tend to suffer from vibration problems. So 3 is the lowest practical number of blades (There are single-bladed turbines, but they are funny looking and need a big counterweight opposite the single blade to balance them). There are diminishing returns to adding more blades. Expense and complexity goes up quickly, but performance only improves marginally. Also, adding more blades tends to increase torque, but at the expense of speed. So you rarely see an electricity generating wind turbine with more than 5 blades, because generators like to turn fast. In applications where torque is important, you may see turbines with lots of blades, like the ones pumping water on ranches, but they don't make good electrical generators unless their output is geared way up to make enough speed for a generator.

 

Q. I understand the mechanical aspects of your wind turbine, but electronics part is all Greek to me. Can you teach me enough electronics to understand this system?

A. Sorry, no. There aren't enough hours in the day to even attempt to respond to all the requests I get.

 

Q. Can you design a wind turbine/battery/charge controller system for me that will power my home/farm/studio/cabin/office/barn so I can get out from under the thumb of my evil electric company?

A. Sorry, no. There aren't enough hours in the day to even attempt to respond to all the requests I get, let alone actually design anything.

 

Q. Do you have a printed circuit board or board layout for the charge controller?

A. No, but the web site I based my charge controller on does have a PC board layout for their controller. It is almost identical to mine. The link is http://www.fieldlines.com/story/2004/9/20/0406/27488

 

Q. I tried building a charge controller using your schematic and instructions, but I can't get it to work. Can you help me troubleshoot and/or repair it?

A. I get lots of these questions. Without actually having the unit in front of me, the probability that I can help you find the problem is just about zero.

 

Q. Can you build a charge controller for me?

A. No. I only build equipment for my own personal use.

 

Q. Can you sell me a wind turbine?

A. No. I am not in the wind turbine mass-production business. Also, see answer above.

 

Q. Will a solar panel charge controller work for my wind turbine?

A. Unlikely. Most solar panel charge controllers simply disconnect the panel(s) from the battery(s) when full charge is achieved. This leaves the solar panels open-circuited. This is not a problem for solar panels. However, wind turbines need to be connected to a load at all times or they will over-rev. When the batteries achieve full charge, the wind turbine needs to be connected to another load, rather than open-circuited. It may be possible to modify a solar charge controller to do this, but it would depend on the particular controller. I can't help you with selecting a controller or making modifications.

 

Q. Do you sell your excess power back to the electric company? Can I do it?

A. I don't sell power to my electric company because there is no electric service on my remote property. It would cost me many thousands of dollars to have power brought in. I'd probably never recoup the cost. Can you do it? I suppose so. However, you need to do some figuring to see if it is really worth it. First, how much excess power do you really have to sell? Next find out how much the utility will pay you for the power. When they sell it to you, you have to pay the retail rate, plus fuel charges and so forth. When the utility buys power though, they only buy it at the wholesale rate, which is considerably lower. You'll need an expensive synchronous inverter to match the power line AC frequency, and professionally installed switch gear. After crunching the numbers, you may find it isn't worth the effort.

 

Q. Which direction does your wind turbine spin?

A. When looking at the turbine from the blade side, (as opposed to the tail side), the turbine spins clockwise. So the motor shaft turns clockwise. The direction of spin is not really all that important. A DC motor will act as a generator no matter which way it is turned. The polarity on the output will just reverse if the direction is reversed.

 

Q. How many birds has your wind turbine killed?

A. My wind turbine hasn't killed or injured any birds.


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EHarmony

 

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