One Man's Adventures into Renewal Energy

Solar Panel

Night - 0 Watts

Battery Bank

Very Low - 11.66 Volts
Battery and Panel Stats Updated @ 30/05/2017 00:55
Please help me to continue hosting this website & associated costs by donating £2.
In return, I'll email you a ZIP file containing arduino code + all images from the website + some extra ones that aren't on the website...all in high res (370MB of pics!).

DIY Horizontal HAWT Wind Turbine / Generator MKII

24th February 2014

I've been making some improvements to the Wind Turbine in the hope of improving its efficiencies.

One of the most major changes I've made is to move the location of the Wind Turbine. My garden isn't especially big and is enclosed on one side by my house and on the other with a load of trees. This doesn't make for good clean wind flow through my garden. What I should do is mount it up high, but that just isn't a good idea in the middle of suburbia. But what I found with my original mounting that was close to the fence line and the trees is that is just didn't spin all that often. I reckon this was down to turbulence - The wind was almost curling and creating a vortex as it hit the trees, making the turbine behave erratically and losing speed. I've since moved the turbine to the opposite corner of my shed and things have improved dramatically. You can see from this video -





Here are the other changes I've made -
DIY Horizontal HAWT Wind Turbine Shaft
The parts I used -
I bought a 10mm bolt from my local DIY store. Using an angle grinder I removed the hexagonal nut from the top, leaving me with a very strong, rust resistant, pre-threaded shaft.

2 x 10mm internal diameter pillow blocks. Cost £10 from Ebay. These are lovely little things, very well engineered and just feel solid and proper. The bearings pivot within the casing, which means that you don't have to get every super straight when building it, and just let the bearings align everything for you.

Motor - I found this 24v motor and was going to use it, but I decided against it. Even though it's a solid motor and would undoubtedly perform very well, it's just too torquey and I doubt my little turbine would have sufficient force to drive it. It just happened to be in the picture!!



DIY Horizontal HAWT Wind Turbine Bearing
One aspect of the turbine I've been pondering on a lot is how do I create a nice 360 degree bearing to allow it to turn into the wind.
I read on another website about how someone had used a chair caster to do this.
So I went off to Ebay and found the one pictured for £2.
It was crap! - the thing had so much play in it, it was ridiculous. It was so bad, that I didn't even get as far as trying it in the wind.
I think people have had success using these kind of casters, but I think there's must have been much more superior quality to mine.



DIY Horizontal HAWT Wind Turbine
Apologies for not taking more pictures of the build as it progressed, I was a bit fixated on getting it built...so you'll have to make do with an underside picture of the turbine.

In the picture, you can see the shaft running through the two pillow blocks.
You could argue that I could reduce friction by only using one pillow block, which I guess would make things turn fractionally easier, but by doing this, you would push a considerable amount of load onto the motor coupling and motor bearings.
I've read on more than one occasion of folks having to strip motors and replace bearings because they've worn out. In pretty much all cases, this is where the blades/hub have been attached directly to the motor shaft. IMO - this would create huge lateral loads on the bearings within the motor, especially when you throw in massive amounts of gyroscopic forces- ie, blades, hub and shaft want to stay in one places due to gyroscopics, but motor wants to be in a different position due to wind direction changes.
By using two pillow blocks, the whole thing becomes very solid and the motor and coupling are left to just get on with the rotating forces and not any lateral forces.

I attached the motor to the MDF using an exhaust clamp. This fixes it very firmly. You just need to ensure that everything is in line with each other to ensure the shaft runs straight and true. My suggestion would be to tighten the bolts on the pillow blocks and exhaust clamp gradually, each one a bit at a time.

The bit I circled in red is my 360 degree bearing (after I ditched the caster idea!).
It's nothing more than some square aluminium with an inside diameter of 10mm.
Capped off at the top with a bolt, which also acts as a fixing point.
And then a u-bolt at the bottom for a second clamp.
Make sure this is at right angles to your frame.
This gives me about 150mm of sleeve for the 10mm pole fixed to my shed.
With a bit of grease squirted inside, I've ended up with a very slick moving bearing that has zero wobble. The top bolt may eventually wear out, but I reckon it'll take a long time for this to happen.

I screwed on a piece of half-pipe rain guttering to act as an umbrella to keep most of the rain out.

For reference, the mdf is just standard 15mm stuff. I know this wont last 5 minutes in the outdoors - this is still in concept stage and I'll probably end up using aluminium box section.

As for the blades - these were stolen from my MKI turbine.






Comments

Robert - 02/06/2014 07:59:37
Hi... me again. Your vertical windmill is a better (IMHO) idea. I think that your biggest problem is that you need more torque. In the system that i am building, I am using a 26 inch bicycle wheel with a 5 gallon bucket cut into 3 vanes. Just some more food for thought

Marko - 02/04/2014 14:43:28
Nice work, really appreciate your DIY efforts and in-depth explanations. Would also like a FIT for my planned DIY install, aiming to get about 2.5kw of panels and some wind power. Will keep following your progress. Thanks, Mark

Name

Email Address (won't be shown)

Human Check - What colour is the sky?

Comment











Copyright 2017 BinaryOrbit.org