What kind of motor should I be looking for to use as a generator?

[Snacks]

I posted a "WANTED" add on FreeCycle asking for treadmill motors or any permanent magnet motors. The response I received is:

I was just thinking I might have something lying around in my basement or garage or something.  Can you give me some examples of household equipment that might have this type of motor?

I'm only just starting to learn about what kind of motors make good generators, but can anyone give me advice for what this person should be looking for in their house? I want to make a small, PVC blade design, and initially plug that into a grid tie inverter. Someday, I'd like to have a deep cycle battery bank, some solar panels too, and remove myself from the grid as much as possible.

This is my first post, I hope to hand out here a lot though.
Thanks in advance!

NB

[ghurd]

Start with the math to get a ball park idea what RPM will start charging.

14V(battery charging) / motor plate Voltage X motor plate RPM = RPM to start charging a battery.
Example-
90VDC 1750RPM 5A 1/2HP motor.
14 / 90 X 1750 = 272RPM to start charging a 12V battery. That is "Cut In RPM".
With PVC blades, want to look for a motor that cuts in below about 375RPM.

Be aware 5A is about the limit that should be pulled from the motor at any voltage.  Can go past it some.  Too much past it will burn the coils out.
Meaning that motor is good for about 5A x 14.4V = 72W of output... In a strong wind.

Grid Tie?  72W is about 1 cent worth of electric per hour... IF the wind is strong enough to make 72W... and it usually is not.
Most places, it will be very hard to make 5 cents worth of power per day with a treadmill motor and PVC blades.
Add up the cost of a Legal grid tie inverter, disconnects, additional electric company service charges, etc... And you will lose money.  For certain.
Going gorilla is no longer an option, and legally never was.
Some meters will actually charge you for the power you send back into the grid.  Others send an error signal to the electric company, who can shut off your power. Etc. Etc. Etc.
A bit about the costs of grid tie.
http://fieldlines.com/board/index.php/topic,133938.0.html

Meaning you want to charge batteries.
G-

[Snacks]

ghurd,
  Thanks for your help and explanation. It looks like I'll not need to spend any money on a tie inverter any time soon. Ok, I can deal with that. So, tonight, I ran across 4 motors that were sitting in my dad's garage. Below are the specs:

Model: Packard
Amp: 3.1
RPM: 1075
VOUT: 208/230
Hz: 60

Model: Universal Electric
Amp: 3.73
RPM: 890
VOUT: 240
Hz: 60

Model: GE
Amp: 2.1
RPM: 1050
VOUT: 240
Hz: 60

Model: MagneTek
Amp: 2.2
RPM: 1075
VOUT: 208/230
Hz: 60

Your comments mention VDC. Can I use the above motors as generators? From what I've seen, I think I can, I just need a AC to DC converter to store the charge.  Is that correct? And if so, which motor would be best?

TIA,
NB

[ghurd]

For a first 'quicky' project, probably best to start with a Permanent Magnet DC motor.
None of those are PM DC motors.
Treadmill motors and Ameteks are PM DC.

There are ways to get power out of those AC motors, but it can get complicated.
Best bet to get wind power out of the motors in the garage is a conversion.
Conversions require machining the armature and properly adding neo magnets.  Google Zubbly Conversion.
Those AC motors are kind of small, and single phase.  Larger 3 phase are better suited to a full blown Zubbly conversion.

G-

[Snacks]

I'm having fun educating myself on this process, thanks so much for your help. After reading several posts and doing my research, it finally struck me I don't have enough room to put up a hawt. Here's a bird's eye view of my property from BING maps:

http://i214.photobucket.com/albums/cc87/neilmbrewer/home.png

NOTE: Your oversize photo converted to a link. Read the photo posting rules before posting photos
The black lines represent my property line. Red lines are power lines.
I hadn't even really thought about getting the city's approval for erecting a hawt, which I now suspect will be a big NO due to city limits and limited space. So, I'm changing my approach to building a vawt. In that pic, notice the small blue line I think would be ideal for a vawt. There always seems to be wind funneling between the two houses right there next to my carport, with winds coming from the west mostly. And I think people would just see it as yard art.

So, I'm starting to research vawts, and any advice on motors, design, legal matters, etc. would be appreciated from you or anyone else.
I think I'll try Sam's design as found here:
http://www.greenenergywindturbine.com/v8_4/preview.html

or here:
http://www.youtube.com/watch?v=auULMyMoJPU&feature=channel

Another question, how do I weatherproof the motors?

Thanks!
NB

[ghurd]

Something to consider about drag based VAWTs.  Half the "swept" area is going up wind slowing down the working area.
On the one in the link, I will guess it has a total area of about 6 sq ft?  Making an effective area of maybe 3 sq ft?

In perspective, this has a swept area of 3.55 sq ft.




Not sure which one the neighbors and city would have an issue with, but my bet is the VAWT would get a lot more negative reaction.
G-

[TomW]

G;

Nice comparison!

I would guess a 3 ft effective swept area VAWT to be near the size of a 55 gallon drum?

One day I hope to get a VAWT but to simply drive some mechanism for fun. Like slowly lift a couple hundred pounds of 3/8 nuts one at a time on a chain of cups then release them on a steel sheet all at once. Over on the end of the land with the barking dogs as a thank you.
 
Just for fun.


Tom.

[ghurd]

Nice comparison!

I debated about using the pic below too, even though it was the 4 blade version.
The blades are 12" long.
It might put it in a better perspective, because it could be considered about 20% larger than the ones in the link.
It's only 7kb, so here it is.
G-