Ceiling Fan Wind Turbine

In short it isn't recommended because it is not designed to work in reverse as a generator. If your thinking of just putting it in the wind and connecting it to the water fountain pump, it won't work.

The topic has been discussed at least once on CR4 here (plenty of info for you) http://cr4.globalspec.com/thread/36062

Additionally there are a few links and videos on the internet.

https://www.google.co.nz/#q=converting+a+ceiling+fan+into+a+wind+turbine

Thank JOT. I have seen those videos, but they never show how or what they connect their wind turbine to. I have also read much of these comments on the forum; however, I couldn't find an answer to my question. I know there's alot of math/electic know how involved...I'll see if anybody else has maybe some ideas...I think there's a way to power a simple small water fountain with a ceiling fan generator, but just need to figure it out. I'll keep researching. Thank you for your prompt reply, I appreciate it.

You need to think in terms of several systems. The output from the fan/generator will be very irregular, more in higher speed winds, to none in still air. the pump cannot react to these swings in available power. You will need a pump that can run on batteries or on a convertor from batteries to the pump's required power. The generator will help keep the batteries charged if it has enough output, or aid in keeping them charged. So, besides the generator you need a charger/maintainer for the batteries and a convertor for the pump. These can be made into one unit. There are several suppliers of this type of equipment. To calculate the need, start at one end or the other - the generator output times the run time, minus the conversion losses equals the available power for the pump, so size the pump accordingly. Or start with the pump you want to use, and work toward the available power from the generator and see if you have enough power or if it needs to be supplemented by another power source. Again, don't forget the conversion losses, they are never zero - you can't get something from nothing. -- JHF

Good luck.

Try this site:

Instructables - DIY How To Make Instructions

Cardboard Savonius Wind Turbine

Thanks!

From what I have seen so far, it is about like cooking a carp on a board. Step 1: get a carp and a board. Step2: Cook the carp on the board. Step3: Throw away the carp. Step 4: eat the board.

Might as well go buy the parts you need to make a good generator, throw away the ceiling fan, and hook up the home-made generator. Or go buy an alternator at the car parts house, and figure out how to spin it up fast enough to matter.

With guys like the cardboard savonius rotor maker helping, (we) he will need all the luck that can be mustered. That fellow with the cardboard has not one clue how the Savonius is supposed to work, and has totally missed the key design element: the airfoils have to shed air flow to the one facing the wind while (it) is on the downstream part of rotation, or the rotor will stall out, and stop turning. It absolutely needs to be as a pair of nested C's when viewed from the top (or bottom), with one C appearing normal, and the other one inverted, with each offset from the center of rotation. On these devices there is no need for a third or fourth airfoil.

Poor example.

Good intentions.

Well, I have to admit my most recent home energy project basically bites.

I took a ten-speed bike, kobbled together a lift frame so that I could use a belt to couple the back wheel directly to an alternator. Frame was laterally unstable - I don't even have the capability at home of arc welding or brazing - so I started spending money. The platform all this rests on was $30 in plywood and 2x4 construction, but that was going to be there anyway.

First it was a $156 or so for a bike exercise stand, then I spent about $250 at a car parts house for alternator, wiring, switch, voltage gauge, connectors, battery, battery box, and another $80 on a decent inverter to use with the battery.

So now I have a folded design where I removed the "fan" off the exercise stand and replaced with an 8" sheave, with that being in the most aft position, then forward of that is the alternator mount and tensioner bracket (homemade stuff that actually worked), just out of the way of the pedals. Barely any clearance between the positive post on the alternator and the left leg of the exercise stand, so I insulated both a bit.

Last night, I managed to complete the wiring layout and all connections, and switch on the lamps and voltage gauge (voltmeter), showing 12 V, lights all lit up the first time, etc. The only problem is I can barely pedal the bike now, so I get to run through everything again to see if I missed something, or if the 8" sheave is just too much for my horsepower. I think I have it geared up too high.

So I totally get it about poor examples, but good intentions.

Here is a possibility of making a better cardboard Savonius Rotor airfoil section:

Using large cardboard heavy stock from a storm door, cut the pieces so that the corrugations run in the vertical axis of symmetry of the piece. Saved up coat hangers (from uniform supply service???) used as a source of reinforcing wire, run the straightened wires up through the corrugations every so many (4th or 6th) row. Use brazing torch and rod to join pieces of wire into longer length as needed. Use the wire to fasten the airfoils to the top and bottom plates (similar to bike spokes maybe). Top and bottom plates can be 1/4" plywood, although I suspect that slightly heavier plywood be used for the bottom plate. Cut circles of the appropriate diameter to the rotor design. Once the rotor parts have been assembled, Use a suitable laquer to add structural strength and rigidity to the airfoils, and paint the top and bottom plates as desired. Mount a thrust bearing on the bottom plate, and another bearing for tangential loading (due to wind shear force) on the top plate. Outer mount plate of upper bearing can also be plywood, and is provided with holes to outrigger pieces (small angle iron or aluminum should work, 4-6 each of these), attach guy wires to these to hold the vertical axis steady. Bottom plate can be made into an effective sheave for running the alternator by using three pieces of different diameter then routing to a V-groove. Alternatively, install a rubber strip on the outer radius of the bottom plate, install a friction wheel on the alternator, and have the alternator spring loaded against the bottom plate (that must be free to rotate, obviously). Hopefully, this will increase rotation speed of the alternator enough to make it useful in a steady breeze.

Search. Read. Search. Read. There's tons, TONS, of information on making wind turbines on the web.

A couple of things to note before you begin. There's only so much energy in wind. There's a concept called 'swept area' which is the area inside the turn radius of the turbine. The amount of energy you can harvest from wind is limited by the swept area. To get a lot of energy, you need a large radius turbine. A 3 or 4 foot turbine will not generate more than about 100 watts.

The cheaper ceiling fans are induction motors with single coil. A single coil will only get you a single phase of AC out. This will be different from the AC that you get from your wall outlet. It will be at the frequency of rotation of the turbine or a multiple of it depending upon how many magnets you put in. The voltage will depend on the strength of the magnets as well as the rate at which the turbine spins.

The voltage will not likely be anywhere near AC line voltage. Your best bet to rectify it to DC and store it in a battery. You'll also need to find a fountain pump that runs off of DC.

Typically induction motors are converted by machining, grinding or somehow creating holes to insert magnets into the rotor. This allows the magnets to spin inside the coil creating the rotating magnetic field that induces the current in your coil.

Here's a link to a site that I've suggested before:

http://www.fieldlines.com

It's run by some very experienced DIY'ers. It's a treasure trove of information on alternative energy sources. There's a huge amount of info on wind turbines. Read through the site first. Search for ceiling fans and you'll see posts from people who've done it before.

I like that idea. Far more efficient and much easier for the novice.

THanks Lyn, I think I'll learn alot...this isn't supposed to be a really involved project...maybe my next project will be, but this is just kind of an intro type project for me.

It's hard to go wrong with technology this old. Before everything was electrified, everything used to be run from wind power. I can still remember the wind powered water pump on my grandparents farm, and even the old "wind charger" that used to charge a bank of 2 volt batteries(in glass cases) that was used to power the DC lights in the farm house.

Simple but effective.

The quick-and-dirty answer can be narrowed down to this:

No matter what you do to this ceiling fan-cum-wind turbine, you cannot get more energy out of it as a generator than it could consume as a fan. So look at the nameplate of the fan for information on motor power rating, that is your UPPER limit of the physical capability of it as a generator. All you are doing with the neodymium magnets is allowing rotor field excitation without being grid-connected. But the windings are still the windings and that is where the limit lies.

Here are some industry typical values for common residential ceiling fans:

52" ceiling fan (high speed) = 90W

48" ceiling fan (high speed) = 75W

36" ceiling fan (high speed) = 55W

42" ceiling fan (low speed) = 24W

So what you get out of yours will depend on the wind speed and size of the motor, but I seriously doubt it will be more than 90W. Depending on what expectation you have for your fountain pump, that might be OK though. However even if you get AC from the fan, the fountain pump will not like the variable frequency you will get unless you are planning on some sort of mechanical speed control. So my suggestion would be to run this through a rectifier to make it DC and charge a battery, then use a 12VDC fountain pump.

I'm not sure I get your angle on the ceiling fan idea, but thanks for the watt information...I'll pick and chose what's helpful.

Firstly, great question, I bet there are many around wanting to understand better such ideas.

Secondly, you have already received some great answers/help.

Thirdly, you are going to have a lot of fun, and maybe a few tears, BUT YOU WILL LEARN A LOT!!

My only contribution is that the fan you have should deliver some great mechanical parts that you can use to your advantage, but the electrical bits generally will hold you back....

There are many websites showing you different ways to achieve what you want, also how to rectify the output (assuming you avoid brushes and commutator, a good idea!).

Magnets on the moving bit and field coils on the fixed part.....is often a good move!!

Have fun and keep us up to date....

I do not think this is a good idea. Those fans are not made for that purpose. They are designed to move a large amount of air at a slow speed. That is exactly opposite of the what the OP needs.

So this means it is going to be very difficult to keep the fan pointed the correct direction with the wind and will more than likely have to be adjusted manually which brings up another issue:

That means you are going to have to get close to it and after that non-sealed motor and windings have been exposed to water and elements it is not going to be safe to be around.

If you do get it pointed in the correct direction and if you have enough wind, that thing will take off way too fast without a brake on it. The blades are just not the correct shape for what you need.

I think this project has several unpredictable, unsafe features and facets that the OP may have to learn the hard way. I just hope no one gets hurt.

What a Negative attitude. I think the OP realizes everything you say but it still is an interesting experiment. It will need a lot of learning on the OP's part, but that is what is good about it. Everyone needs to play. I used to play when I was a kid. I enjoyed my college years when I "played" in the Labs. (I was always changing things from the assignment.) I spent the first years as a design engineer but was put in a team of 3 to redesign a new product and we 'played' with the design. Fun Stuff. Then I went to work in field engineering working with large industries. My manager kept telling us to go out and play and have fun. It was a great job and the customers loved us. I remember nearly always being thanked for what I did while they were signing time sheets for billing of several hundred dollars per hour.

I say to the OP, go ahead and play, don't expect much, don't spend much money, free items only, and be careful and think of every danger you can imagine. If I were doing it I would inspect the motor to see if there are any electronics that need to be stripped off and do so. (You can always add them back) Spin the thing by hand and measure the voltage, frequency, available. Put a small resistor in that can handle the voltage calculating the wattage maximum that could exist and then keep changing the resistor until you have one that can measure how much power you can produce. Mount the thing with a manual lever to direct it to the wind and see what you get. If you think you can get enough power based on pumps you hope for then figure out some automatic way to aim it into the wind. Weathercocks or windmills would be a start for a design. Probably the hardest and most important is to provide some way to slow or stop the blades in high winds. Redirecting is one possibility or a mechanical hub brake is another triggered when the voltage goes over some value. Definitely use a rectifier to change the AC to DC and use of a battery would dampen the highs and lows. Don't expect a lot of success in the final result, true success is when you learn something. Have fun playing. If humans didn't play, they would still be living in trees and caves, eating their food raw, and catching it with their bare hands.

Good!!

Thank you for the encouragement!

From all points of views this is a no-no project: a) The ceiling fan is a motor not an A/C alternator regardless of the magnets efficiency from back-conversion, even if you could find a way of exciting the rotor windings, is very low. In commercial so called generators, the excitation issue is crucial for proper voltage generation. b) The wind velocity and the fan blades would have to be optimized to produce enough power to be of any use. This is very important issue even on proprietary wind alternators designed for this purpose. c) Rotary speed (RPM) is crucial for producing 60Hz constant frequency. Any A/C motor loads you are planning to run are strictly frequency dependent on steady frequency in order to work and maintain the designed power/frequency relation. In this respect a constant speed/frequency governor will have to be considered and implemented. D) You have to keep in mind that when you start an A/C motor (without an electronic soft starter), the momentary inrush current is six times the normal running load making your fan alternator contraption practically useless for almost all motor loads even small ones. If I were you, I would forget the whole thing and, if (only if) constant high to moderate wind conditions are available, consider buying an OEM wind turbine specially designed for this purpose and for the load requirements you are planning on powering. Even solar panels, battery banks and DC/AC converters are a better solution than your ceiling fan power conversion back-engineered solution. If you would like to go ahead and self teach yourself about alternators (A/C energy producing device) or Generators (DC energy producing devices), there is a vast amount of Electrical Engineering in your local library or in any technical bookstore. By the time you have read all the pertaining literature, I can assure you will either have forgotten your project or grown old and wise enough to know better.

Your reply seems to be based on much larger machines that do sync up with grid. I presume this ceiling fan gen-set will be off-grid, just as is my home bicycle powered alternator.

I think he should save the ceiling fan and go to a junk yard and recover a used alternator if he can't afford a new one. More power can be had with that. Off-grid one does need to worry about (1) any particular efficiency as long as the quantity of power you need is made. (2) do not worry about generating precisely 60 Hz, or even 50 Hz, as you will probably want to go generator AC - DC (battery bank) - AC (inverter). As long as you follow basic rules of the inverter as to inrush current limitations for starting motors, avoid using heating type appliances (unless low wattage microwave), and avoid some types of lighting particularly certain fluorescent lighting fixtures with large ballasts, then the inverter should last a long, long time. Use LED lighting fixtures where possible off the inverter, for the low current draw.

Avoid constant duty motor operations, as this will draw down the battery bank too quickly, unless you really have a lot of power available, and a battery bank with numerous batteries. Choose the type of battery carefully or not.