Tag Archives: salvaged

Build you own Wind Turbine, why not?!

I want this place to be offgrid.

I do not want to rely on a power company that overcharges and dictates to us for something that is all around us.

Electric power in the form of energy is all around us.

Whether it is in Solar, Heat, Wind or Water, there is more Free power around us than we’ll ever need.

So, build a harness for it and jump on for the free ride…

A little test turbine
A little test turbine

The cob house will get it’s power from Solar panels and some homemade wind turbines.

I have been experimenting with DIY wind generators for some time now and decided to put one up the cob house for testing.

This is a very basic 4 PVC blade attached directly to the shaft of a 180 volt DC permanent magnet Treadmill motor.

I mounted the pole very crudely by loading the base with bricks and tying it to the house with wire.
I also erected it in an area which gets blustery wind due the the tree next to it and others in the close vicinity.
I wanted a Worst case scenario benchmark to work from.

Hiding in the trees
Hiding in the trees
Closer view of the basic generator
Closer view of the basic generator

I used a 4 blade configuration so that I required a lower start up wind speed as this has more surface area facing the wind ( called the Swept Area )

4 blades does however mean increased drag and this translates into slower RPM on the motor shaft than a 3 blade configuration.

There is plenty of info on the internet on how to build a generator like this using 6 or 8 inch PVC pipe as the blades.
Below is a schematic on how to cut the blades from the pipe so that you can have 6 equal blades to experiment.
Also, a pic of a nicer looking 4 blade design from http://www.instructables .com
Once again, thank you to the authors.

Cutting schematic for PVC wind turbine generator blade. Horizontal Axis Wind turbine
Cutting schematic for PVC wind turbine generator blade. Horizontal Axis Wind turbine
4 blade PVC Diy Wind turbine generator blades
4 blade PVC Diy Wind turbine generator blades

Treadmill motors are perfect for wind turbines as they create dc voltage at very low RPM (revolutions per minute)
They are normally rated up to around 180 Volts DC at around 2000 to 3000 RPM at 3 to 8 amps depending on the individual motor.

What this translates to is that:If you spin the shaft of the motor at 2000 to 3000 RPM, you will be able to measure up to 180vdc from the motor.
This can then be coupled to a battery through a blocking diode to charge to battery.
The battery in turn can then light DC lights or AC appliances through an inverter.

Very basic, but this is the general jist of why.

Here is a basic schematic of a system in more detail from http://www.homebrewpower.co.uk

www.homebrewpower.co.uk has some great info. Thank you
http://www.homebrewpower.co.uk has some great info. Thank you

I ran a few tests on my basic turbine and was reasonably impressed with the results.
Although the location of the turbine meant that it received very little wind whilst hiding on a low pole behind in the trees, I was able to glean good info on how to build my next turbine capable of supplying at least 40% of my proposed needs.

The new turbine will be mounted on a salvaged fiberglass street light pole approximately 12 meters high in a high wind “traffic” area.
It consists of a 6 blade 1.7m diameter turbine with an 1:11 ratio turning 2 x 2kw Treadmill motors via a belt.
Therefore 1 revolution of the turbine blades will turn the motor shafts 11 times.

Example: 100 blade RPM = 1100 motor shaft RPM

Here is the beginning of this experiment:

Upcycled  Wheelchair rim will turn the belt over the 2 treadmill motors. Not pretty, but she'll be effective!
Upcycled Wheelchair rim will turn the belt over the 2 treadmill motors. Not pretty, but she’ll be effective!

It is useful to know a few things about Wind turbines if you are looking into building one for your own uses.
Some of these include:

Air density: at the coast and in lower lying areas, the air is denser due to the amount of water vapour in the air.
This means that the wind is “heavier” and carries more strength than the thinner air of higher altitudes, meaning faster RPM on the blades at lower wind speeds due to the
Power of the heavy air.

Air power versus elevation
Air power versus elevation

The higher the turbine, the more effective:
Turbines mounted on higher poles do not suffer as much from bluster wind which has bounced off of obstructions at lower levels.
These obstacles also take a lot of the power out of the wind.

Tip Speed Ratio:
This relates to drag on the blades.

Weight of Blades: heavier blades require more power from the wind to turn them. Some people do preferred build blades out of wood, but the preference is the lighter, the better.
Hence, blades cut from PVC pipe offer lightweight solutions to this.

Flexible blades reduce efficiency:
Blades that are too flexible or cut from soft materials and bend back more than about 5% in good wind are hindering the efficiency with increased drag.

DC Motors: all DC motors can produce voltage when coupled to blades, but rather look for motors with lower rpm and higher voltage ratings. This means that your turbine will not
need to spin stupidly fast just to light and led or charge a mobile phone.

Blade design: fewer blades mean that the turbine rotate faster with less drag but will need higher wind speeds to start it turning.
More blades mean slower start up wind speeds but slower blade speeds. Search Tip Speed Ratio for more info on this.

Advertisements

Tree felling 101

As mentioned in the last post, I don’t have loads of cash to throw at removing these trees. So, I do it myself. What I have had to build and experiment with is Tree Climbing spikes. These little buggers help you to climb stupidly high in order to get to the tops of the trees for cutting. They are effectively just a long spike protruding from the inside curve of your boot, which you kick into the tree to give you grip. Put a rope around the tree to hold on to and go.

Obviously, climbing harness, carabiners, safety ropes and such must accompany you!

DIY Tree Climbing Spikes
DIY Tree Climbing Spikes
DIY Tree Climbing Spikes 2
DIY Tree Climbing Spikes 2
Tree Climbing with Spikes DIY
Tree Climbing with Spikes DIY
Up a tree to secure a cable
Up a tree to secure a cable
Cable secured
Cable secured
I ALSO WANNA CLIMB DADDY!
I ALSO WANNA CLIMB DADDY!

On most of the trees that I have recently felled, I was allowed enough space to let the tree fall where I wanted it to. To do this I climbed the said trees and secured a long strong cable at about two thirds of the way up. I then fastened the other end to the Jeep ( normally snaking around the base of a tree in the direction I wanted it to fall) I loaded the Jeep with bricks and rocks to weight it down for more traction, put it into Low Range and pulled the tree as tight as possible. I then fired up the chainsaw and cut out the ‘V’ near the base of the tree in the direction I wanted it to fall. I I then cut around the sides and back of tree until I heard the tree shift and start to lightly click as the heartwood fibres took strain. I then sprinted my ass off to the Jeep, started it up and pulled.
Some times I’d have to repeat the last 2 steps a few times before the tree gave way. (Better safe and tired than sorry) The tree would begin to shift under the torque of the vehicle and start coming down. I would keep the tension on the cable for as long as possible to ensure that the tree fell exactly where I wanted it. Even on the badly leaning trees I was able to land them near on perfect.

20140504_11103620140504_11100620140504_120802inthetreescobhouse.wordpress.com tree removal

Cob house Inthetreescobhouse grass roof

MY NEMESIS:

The last tree on the menu on Sunday had been giving me a worried finger for a long time. I
It had been shaped by the prevailing South Westerly wind to curve from it’s base to midway and then straighten up but keep all of it’s weight and foliage on the wrong side.
Cutting it at the base meant dropping it possibly on the house and definitely on the neighbor’s fence and chicken coop.
No vehicle in my reach would be able to pull it over against it’s strength and weight.

So, suck it in, climb and cut..

Mr Nemesis
Mr Nemesis
Rather high,  Mr Vertigo.
Rather high, Mr Vertigo.
And the wind started picking up!
And the wind started picking up!

It took me about an hour before I started to cut up there with the chainsaw. Life at that height is a different world.
I even phoned my wife to come and give me moral support!
I managed to cut all the weight off the tree to then cable it and cut/pull with the Jeep.
Done. Yay!

My girls coming to give me moral support! I was trying to pretend I was on a ship's mast by singing a sailor's songs!
My girls coming to give me moral support!
I was trying to pretend I was on a ship’s mast by singing a sailor’s songs!

Where we are today.

So, we’ve got the roof on, we’ve thrown a cement floor throughout, we have the basic fireplace, water tank and feed done, now we are busy boxing the walls, filling them with wattle and cobbing them in…

Next will come the electric points, db boxes for the solar, home rebuilt solar geyser with rocket water heater, internal walls, skylights and eventually ceilings (eventually love…not now!)

18th Jan 201420140126_180306 20140202_173048 20140201_081452 20140118_140000 20140202_173048 20140202_173157 20140205_224833

“Life is what happens while you’re making other plans…” So here’s the plan…..

IMG-20121230-0107818th Jan 2014
After a few years and a lot of life, we (dad, mom and the 3 little people) have decided to build a cob house.

We were originally going to buy a standard house in the suburbs and become what we didn’t really like. Suburbians.

-Nothing wrong with that, but my wife and I have never been conventional. She is an inspired artist and I am something of an artistic soul too.
(Altough we are both rather disgruntled artists as kids, bills, work, building, money and life like to bubble the pot!)

So. We looked at conventional houses in the suburbs. My wife ran away screaming to the hills. I followed her.

We found a beautiful wooded plot just out of town that a friend of ours was wanting to sell off. Perfect!

We jumped at it!

Well, it has not been smooth sailing by any stretch, having to clear trees, fence, build, wait, pay, wait, change plans, correct title deeds, wait, pay…. all another story!
But, seeing our house take shape is really exciting now.

This blog is about how we are building our little house out of natural and recycled materials to be free of grid electricity and most importantly:
To be free of a mortgage.
We are trying to do everything without taking loans, so progress is slow.

It is quite funny how our new home has morphed and warped from where it was just going to be a little workshop for me (dad) growing into a fully fledged offgrid, living grass roof, skylighted, 3 bedroom home capable our keeping us 5 cozy and happy!

We had no training or experience in building alternatively before starting here, everything was learnt by studying the internet, watching YouTube videos, looking at pics and mostly:l lots of trial and error.

I’d like to dedicate this blog to all the wonderful people of the world who have posted their findings and ideas and shared their knowledge on the net.
It is a wonderful brotherhood of barefoot builders that helped us shape our ideas and we’d like to give back to those who also want share in the joy of the Hand Built home.

Well, here is our lovechild…