Deciding which motor to use for my 1st wind turbine

New to renewable energy? Have questions? Here's a great place to ask them and view information about wind and solar power basics.

Deciding which motor to use for my 1st wind turbine

Postby Elfiend » Wed Jan 14, 2015 1:42 am

Hey everyone, wind energy newbie here, wondered if I could get some advice on which of the following would be the best route to go or if I should find a more effective motor to build my first wind turbine.

1) GS 2hp Permanent Magnet Motor Ratings 15 Amps 130 VDC @ 6600 RPM
2) Baldor DC Industrial Treadmill Motor 3hp 15 Amps 180V 3200 RPM

If I calculated correctly the 1st motor I posted would need to spinning at about 609 RPM’s to produce 12V and the 2nd one seems more promising since it would produce 12v at 213 RPM’s or so. I think the 1st one needs to spin way too fast so what would my options be to make a wind turbine out of it? Gearing it? Amplifying voltage circuit?

The installation site would be an off grid farm that is on top of a small mountain that always has a constant breeze with it’s occasional high speed gusts. I believe the 1st motor (GS) is brushless and the 2nd one (Baldor) has brushes. If I can generate useful electricity I will definitely look into getting more motors/ building more windmills. The GS motor seems a little more simple, with just the positive and negative cables. The Baldor has a few more cables (Green, White Black on one side and thinner Red Green Black plug on the other) . I can only get a very low voltage reading when I spin it by hand out of the plug side, with no reading coming out of the back end (thicker cables). The person that gave me the motor mentioned that the brushes need to be replaced so I thought that may be the issue but I unscrewed the plugs holding them down and they seem fine with quite a bit of carbon left. I am new to dc motors/ wind energy so sorry for the dumb questions. Maybe someone has more experience with the industrial treadmill dc motors and can help me test it out with my multimeter (The numbers seemed great but I know that brushed motors aren’t the top choice, got it for free so figured it was worth a try). It is from a Landice Treadmill you can see it in this youtube video: https://www.youtube.com/watch?v=W2BZpKNWVEA . If not it is very similar to the one in the video.

I have access to another PM treadmill motor with the following specs: 2.65 hp130vdc 18 Amps at 6700 RPM but I figured it would also need higher RPM’s to produce a usable voltage (I did get about 4 Volts spinning it by hand). I also have a small radiator fan motor laying around. I spun it around with a drill and got a little over 4 volts DC but I don’t think I can do anything with that low of voltage but correct me if I am wrong. Oh I also have an old alternator sitting around if I could use it for anything.

Again I apologize if some of these things have been asked over and over. I have tried to read up on different diy windmill forums for a couple weeks. Cross posting on a few websites to see if I get more feedback. Thanks a bunch
Elfiend
Solar Supporter
Solar Supporter
 
Posts: 2
Joined: Wed Jan 14, 2015 1:41 am

Re: Deciding which motor to use for my 1st wind turbine

Postby Gordon-Loomberah » Wed Jan 14, 2015 9:16 am

I think it is always a risk using such high voltage and power motors for a small 12V system, one day the wind will blow hard and there will be too much power to handle.

I built a WTG over 20 years ago that used a 24V truck alternator, and got a bit over 1kW out of it when it was blowing at 30 or 40km/hr, but I had to gear the main shaft up by over 5:1 (with sprockets and chain) to get the alternator to spin fast enough. The blades I carved out of marine plywood, and overall diameter was 3.6m, with a tip to wind speed ratio of about 5:1. Despite messing around with various methods of lubrication, the small sprocket on the alternator kept wearing out every few months. I also tried belt drives, but they didn't last long enough either, so there was lots of maintenance- which involved climbing up a 21m high tower high on a ridge. My suggestion is not to bother with gearing up!

...on top of a small mountain that always has a constant breeze with it’s occasional high speed gusts.


Have you measured the strength of that constant breeze? Generally a breeze doesn't have enough power to generate a useful amount of electricity, you need a reasonably strong wind. You really need to collect wind data over an extended period to see if wind power is viable at your location. Ideally, a WTG should be located 10m above any nearby obstacles, so you'll need to spend a fair bit of money on a decent tower to hold those heavy motors securely.

For the expense, time and effort you are probably better off buying a few solar panels, which will probably produce significantly more energy, with minimal maintenance.
http://gunagulla.com Loomberah weather and astronomy including live solar radiation intensity and UV + Gunagulla aquaponics, organic eggs and cherries
User avatar
Gordon-Loomberah
Community Moderator
 
Posts: 5763
Joined: Thu Sep 24, 2009 9:41 pm
Location: Loomberah NSW Australia

Re: Deciding which motor to use for my 1st wind turbine

Postby Elfiend » Wed Jan 14, 2015 10:59 am

Thanks for replying Gordon. I do have a small solar setup that I want to add to as budget allows. I just got these motors for free and have a lot of material around to build a tower with. Average wind speed is 8-10 mph. I do worry about producing 12V from these higher voltage motors; Is there any kind of brake that could be applied over a certain RPM? As far as the alternator I was contemplating of making a bike generator to help charge the batteries in case of the other systems failing.
The industrial motor does weigh quite a bit which concerned me when I first picked it up. I haven't removed the big flywheel though since I do not have a gear puller which I can guess may cut the weight in half but still at least 10 lbs to strap/bolt up 10-20m up.
Elfiend
Solar Supporter
Solar Supporter
 
Posts: 2
Joined: Wed Jan 14, 2015 1:41 am

Re: Deciding which motor to use for my 1st wind turbine

Postby Gordon-Loomberah » Wed Jan 14, 2015 11:31 am

A furling mechanism built into the mounting to turn the blades out of the wind is probably the best way to protect from overspeed/high voltage excursions. Making and fitting a reliable braking mechanism could be difficult and expensive.

8-10mph wind isn't enough to produce usable power. Whilst the turbine may be spinning at a low wind speed most WTGs are only able to produce a few watts, if anything at all, at those speeds. You really need double that, on a consistent basis, if they are to be useful power generators. Of course larger sized blades with a suitable high tip to speed ratio would help, but that's going to be more risky in strong wind conditions producing too much output.
http://gunagulla.com Loomberah weather and astronomy including live solar radiation intensity and UV + Gunagulla aquaponics, organic eggs and cherries
User avatar
Gordon-Loomberah
Community Moderator
 
Posts: 5763
Joined: Thu Sep 24, 2009 9:41 pm
Location: Loomberah NSW Australia

Re: Deciding which motor to use for my 1st wind turbine

Postby karlajensen » Wed Jan 14, 2015 7:31 pm

use an F&P
i've got a whole kit, blade hub motor holding assembly with mast bearing
and F&P motor

$100 and its yours. Will make upto 350W before needing neo mags or dual stators to get more grunt.

Google F&P, great hobby mill to get your feet wet
8E + 8W + 8Nth Garage CMS2000-1 with ~4500W in 3 strings of 8.
Fronius Galvo 3.0 inverter with ~6.6kW panels
12x ZNShine + 12x 180W Solarfuns both NW + ZNShine 12x190 facing SE.
Edwards Solar Hot water


Luck Favours the well prepared.
User avatar
karlajensen
Solar Crusader
Solar Crusader
 
Posts: 1346
Joined: Tue Oct 13, 2009 9:30 am
Location: Perth


Return to Q&A - wind and solar power basics

Who is online

Users browsing this forum: No registered users and 3 guests

new solar power specials