Shopbot Talks goes Green...

[khalid]

Hi,
Nothing about CNC today :(.. but want to share my success about DIY suntracking... Anybody interested to instal i can help.
Just a short video:
http://www.youtube.com/watch?feature=player_embedded&v=e4WHFN2RDP0
and description on my blog:
http://my-diysolarwind.blogspot.com/

[jerry_stanek]

How much power does it take to move it?

[khalid]

How much power does it take to move it?
The microcontroller is programmed to adjust the panel after each 5-minutes. The motor is windshield wiper motor with PWM control. Its about 2amp running at 50% duty cycle and i think it is taking around 10~12 watts approximately.

I am planning to mount 7 solar panels x 90watt (Total expected wattage around 630watt) on the structure in the video. It adjust the panel in couple of seconds so i don't think it will take more wattage at the end of the day as compared to 20~25% increase in the total solar power.

[myxpykalix]

khalid,
I watched your video and I had had thoughts of doing something kind of similar but for my solar water heater system. I was thinking that it would maintain a higher thermal transfer heat if it was in constant direct contact with the sun thru its east-west travel here during the day.

I used to sell big satellite systems and think i have an old accuator arm and the control for a satellite dish (from like 25 years ago) still laying around and was thinking about trying to set this panel up on a pole and attach the accuator arm to travel the azimuth of the sun in the sky.
Do you think all that is as necessary to do with water as you have with a solar electric? :confused:

[backyard_cnc]

I found some info on controls for a sun-tracking solar collector set-up here.

gerald

http://www.ka1mda.org/ham/homebrew/solar/index.htm

[khalid]

Hi jack,
In your case you can control mirrors to directly put sunlight on the panels. I think such arrangement is called Heliostat , here is the video:
http://www.youtube.com/watch?v=6Q2eWBwgjF0&feature=related

Here is the DIY link,
http://www.cerebralmeltdown.com/heliostatprojects/

Todays i improved my sensor, i have updated my blogsite and following is the video:
http://www.youtube.com/watch?v=xgFo6ijqvCk&feature=player_embedded

[khalid]

Here is the final installation video of the system:
http://www.youtube.com/watch?feature=player_embedded&v=8ksZjPs7qrI
further details can be seen on my blog.

[khalid]

I have been collecting components for few years for fabrication of 1KW horizontal axis wind turbine diameter 12 foot. Last year i purchased 24 Magnets US$5 Ea, a Car wheel hub for making the axial flux generator for the turbine.

Recently did some activities for making this wind turbine functional till the end of September 2012. Structure being fabricated in local market. I have made the CAD model of Wind turbine blades using NACA 2412 profile.

Here is the Magnetic plates of the Axial flux wind turbine.

[khalid]

Today i CNC machined the molds out of 12mm thick MDF for resin casting of magnetic plates.The tool used was 8mm end mill at 70inch/minute using 3mm per pass depth of cut. The mold machining took 35minutes on the CNC router. The cast resin will help bounding the magnet with the CS plates so that the magnets stay at high RPM.

[khalid]

The MDF mold fitted exactly on the magnet plate.

[khalid]

Today i ordered the charge controller(US $235 )for my wind mill with following specifications:

Rated Battery Voltage = 24V
Rated Wind Turbine Power =600W
Wind Turbine Maximum Input Current =40A
Wind Turbine Maximum Input Power=1000W (http://rover.ebay.com/rover/1/711-53200-19255-0/1?toolid=10029&campid=CAMPAIGNID&customid=CUSTOMID&catId=293&type=2&ext=251139492462&item=251139492462)
Unload Voltage(factory default)= 28V
Unload Current(factory default) =25A
Rated Solar Power= 300W
Battery Over Discharge Voltage Shutoff= 22V
Battery Over Discharge Recovery= 24V
Output Protection Voltage= 32V
Display Mode = LCD
Display Parameters

Wind Turbine Power, Wind Turbine Voltage, Wind Turbine Current, PV Voltage, PV Charge Current, PV Power, Battery Voltage,
Over Voltage, Under Voltage, Over Load, Short Circuit, Night. Etc Attached Thumbnails http://www.cnczone.com/forums/attachment.php?attachmentid=166605&stc=1&thumb=1&d=1346511823 (http://www.cnczone.com/forums/attachment.php?attachmentid=166605&d=1346511823)

[khalid]

completed the MDF coil winder on my CNC machine.

[dana_swift]

Looks good. Are you mounting the MDF on an indexer to wind the coils like it shows in the first photo?

Do you use a iron laminated core when its finished winding?

I have had the same general project in mind for a few years. I am envious you are getting yours done first..

D

[khalid]

Looks good. Are you mounting the MDF on an indexer to wind the coils like it shows in the first photo?

Wow..your idea of using indexer is pretty good..initially my idea was to hand wound the coils.


Do you use a iron laminated core when its finished winding?

No, no laminated iron core... I am following Huge Piggott wind mill design guide. However the dimensions varies due to scrapped low thickness magnets etc.


I have had the same general project in mind for a few years. I am envious you are getting yours done first..

D
Hope i shall finish the project till 20 september, 2012.:D

[khalid]

As the drawing development in progress so the parts coming out from my home made CNC machine.You can see how accurate is my home made CNC router compared to a part produced with a precision industrial CNC machine.

[dana_swift]

The indexer on the shopbot can run in continuous turn mode (with the upcoming release). I figure to put a prox switch on a spool and have an arduino count the turns. Alternatively, I could have it turn 10 turns, and zero the indexer position in the new position. Repeat until the number of desired turns has elapsed. Then I have a cool CNC coil winder..

My wind project will happen. I have a place to put it, and a general strategy to evaluate its performance compared to similar designs.

My plan is to build TWO wind generators, and mount them about 50 feet apart. Then leave one in standard configuration, and let the other one be a test bed. Since the wind doesn't blow the same way from day to day, the difference between the two can be compared since they experience almost exactly the same conditions.

Then I can experiment with changes in airfoil, pitch controllers, charge controllers, etc. See which one really performs best with the various wind speeds and air densities it encounters.

Lastly I can plot all that against the cost for each version tested. Which produces the most power for a given investment?

It will be interesting to find out. And hopefully the information will be economically useful.

Khalid I am impressed, and glad to see the ideas keep coming!

D

[khalid]

The indexer on the shopbot can run in continuous turn mode (with the upcoming release). I figure to put a prox switch on a spool and have an arduino count the turns. Alternatively, I could have it turn 10 turns, and zero the indexer position in the new position. Repeat until the number of desired turns has elapsed. Then I have a cool CNC coil winder..
I can make a gcode for my indexer to complete certain rotation and stop. In my case i have to wind each coils 110turns, so making a simple few lines gcode for indexer is not a problem for me.



My wind project will happen. I have a place to put it, and a general strategy to evaluate its performance compared to similar designs.

My plan is to build TWO wind generators, and mount them about 50 feet apart. Then leave one in standard configuration, and let the other one be a test bed. Since the wind doesn't blow the same way from day to day, the difference between the two can be compared since they experience almost exactly the same conditions.

Then I can experiment with changes in airfoil, pitch controllers, charge controllers, etc. See which one really performs best with the various wind speeds and air densities it encounters.

Lastly I can plot all that against the cost for each version tested. Which produces the most power for a given investment?

It will be interesting to find out. And hopefully the information will be economically useful.
You are indigenous. Your ideas are really great. The monitoring of one wind mill parameters and adjustment is a tidious process but the end results shall be a highly efficient wind mill. Dont forget to post your work on internet.



Khalid I am impressed, and glad to see the ideas keep coming!

D
Yes, I highly appreciate your ideas and guidance and thank you for sharing your ideas and out-of-box thinking.

Today i machined the template for marking the position of Stator Holes on the structural frame. This template shall also be used for Resin casting. Moreover, the metallic structure for mounting the wheel hub and magnetic plate is also fabricated. Some snap shots of today's work.

[khalid]

Here is the blade design by my brother Sadiq usman during his final year in Mechanical engineering. Today i carved out a small scale version of it on the MDF using double side machining technique. I found out that the twist in the blade and NACA profile selected is not efficient.

I also designed the blade using NACA profile. I will machine it soon and will post the comparision.

[dana_swift]

Kahlid have you run the equations for L/D as a function of radius for the airfoil you are using?

Given any specific windspeed you can compute what RPM you will get at no load, and approximately how much it will "load up" as you extract energy.

The books I have found to be most helpful on mathematical aerodynamics are "aerodynamics for naval aviators":

http://www.faa.gov/library/manuals/aviation/media/00-80T-80.pdf

And Jan Roskam "Airplane Design" Volumes I and II. Ignore the others. They cost about $50US each. Anybody designing aerodynamic anything usually has a copy on their desk. Its the basic info.

http://www.amazon.com/s/?ie=UTF8&keywords=jan+roskam+airplane+design&tag=googhydr-20&index=aps&hvadid=1182450761&hvpos=1t1&hvexid=&hvnetw=g&hvrand=18445047552113350184&hvpone=&hvptwo=&hvqmt=e&ref=pd_sl_20yf4csix5_e

At first the math of aerodynamics is very daunting. But it condenses down to a handful of equations that are quite manageable. Basic drag polars are available for the NACA airfoils, and lift as a function of alpha (angle of attack) at various airspeeds are known also. This stuff is predictable enough that you can weed out a lot of ideas with a few calculations.

I used to work with a guy who had a sign over his desk that read "One can easily save a few hours in the library by spending a few months in the shop."

Hope the book references are useful. The book for naval aviators is a free download. Also it works in English Engineering units. Although the books are aimed at aircraft, the airfoil doesn't know if you are putting power in or taking it out. The four forces will be in balance or the RPM will be changing.

D

[curtiss]

Thanks for the aviation information Dana, I now have about 434 pages to read...

Of course, one of the greatest moments in aviation history was when Wilbur said to Orville, "You know, If you can't turn, you ain't much better than a cannonball..."

[khalid]

Hi dana,
Thank You for posting the links.

I have found some good stuff for blade designing and making a 3D model.
http://warlock.com.au/tools/bladecalc.htm
http://www.windstuff.org/blades/cad/cadblades.php

but i have no time to make the blade design and cnc machining. My brother has made some 6ft radius blades out of thick PVC pipe i shall share with you.

I have completed the coil winding jig. Meanwhile, i purchased the copper laminated wires SWG 17 number for making coil. The price of laminated wire per Kg is 11US dollar. I purchased 5.5Kg of laminated wire.

[khalid]

At last i received the wind mill charge controller. It took about 15 days to reach at my door step from Hong Kong port :).. It seems very solid and i have also received the software CD to monitor various parameters of the wind turbine.
I also completed the furling tail flapper.

[dana_swift]

Khalid- great links! I like those tools. It may save me having to write equivalent ones. Thank you for the references.

The books I refer to are the fundamentals, they are very well written. Hope you can find the information useful.

D

[khalid]

Dana :) If you have good command on 3D software you can convert the NACA profile into efficient blade using the technique described in that websites links. I shall study the links you have given:)

I made a test coil winder earlier and today i made one coil with 37 turns. I didn't add any varnish coat but the coil is difficult to remove from the fixture ;) ... I shall make another simple jig tomorrow that will ease up removing the coils without destroying.

"Roman" at cnczone posted a helping post in my thread about Coil winding , following are his words for everybody who need to wind the coils:
"About your coil winding jig, I have done many coils and even worked in an electrical motor shop that had a few commercial coil winders.

Suggestion 1; Put the jig on the end of a portable electric drill (with a speed control) and then it can wind automatically. A lathe is also good if it has a low speed.

Suggestion 2; You can paint the coil with varnish or nail polish every layer as you wind it, which will then be a reliable solid coil when done. However this will stick badly to your coil former. If you made the coil former from polyethelene (like food chopping board) the glue will not stick and you can make solid coils then pop them off the former. You might need a small taper on the middle round part, to slide out of the coil.

The magnetic forces on the windings will be high, so somehow they need to be set in resin or varnish. Otherwise if there is any air in the coil the windings will flex and rub because of the magnetic field and soon wear through the insulation and fail.

If putting a dry winding in resin we would put in a vacuum chamber to make sure the resin goes through the coil and no air is present. It is easier to varnish the coil as you wind it, every layer, so I would go for the polyethelene former and do that. Varnish type is not that important, quick dry nail polish is an acrylic and will be strong and bond well later when you set the hard coil into the former with resin."


I hand rotated the magnetic plates and got 1.5Volts (don't know about the RPM) with single test coil. Tomorrow i shall borrow a stroboscope and will plot a graph between RPM and Voltages. following is the formula to get estimated cut in voltages.

Required Cut in Voltages= VAC(of test coil at cut-in speed) x No. of coils/phase x1.732(multiplication factor for 3 phase)x1.414 (DC conversion factor) - 1.4V (diode drop)

The cut-in speed i shall keep around 150~200RPM. You can see pictures of furling flapper that is turned into flag of my country. Three PVC blades 6feet each worked out by my brother one year back . The blades are big you can see pen kept on the center blade for comparison.

[khalid]

One more addition of foolish blunder in my life:D:D
On the first page on the Thread, i posted a CAD drawing snap... Something is very wrong in it.. 12 magnets and 12 coils... Its not possible:D

After casting and painting the magnetic plates and making 9 coils when i assembled the coils around the magnets i feel that i have wide gaps between the coils...
Then i consulted the drawing i made earlier, their were 12 coils.. what a nonsense... no way... This should be 9 coils...

Destroyed the magnetic plates after salvaging the magnets... Now i am going to make new magnetic plates with small diameters...

I am completly lost.. How i did this blunder... this regularly happens in my life...At last i am not a genius:rolleyes:

[dana_swift]

LOL.. we all make mistakes. What is so hard to remember when things go wrong is that we had the courage to get in the pond and swim with whatever wildlife may be waiting. Sometimes we get bitten. Sometimes we get wet. And sometimes we get inspired.

Problems drive inspiration. Your next design will be really cool, I would put money on it!

Thanks for sharing the downside as well as all your great contributions!

D

[khalid]

Dana thanks for your support in this hard time:D I will not leave this project without any achievements...:)

Please never make mistake..learn from my experience.. I am posting the improved coil winder picture that made my life easy. It took 40minutes to make 9 coils, each 110turn with 1.5mm dia laminated wire (SWG17):)

You can see i am arranging the coil for resin casting. I am using electrical glass tape for high temperature. i know some time the temperature of the coil will be high during high winds and not want to make another blunder by using the simple tape.


In the drawing you can see rectangle magnets, its 3 phase , so if you see closely the purple coils are at the center of magnets. It means they are providing the full voltage at this condition. the other coils are in the middle of high voltage range when the purple coils are at high peak voltage.

PS:
i have made the coils first, then measured the dimensions and reverse engineer the magnetic plates. i think this is the easy way to go.
"Sometimes when you innovate, you make mistakes. It is best to admit them quickly, and get on with improving your other innovations. "

[Brian Harnett]

Cool work I look forward to seeing the progress I don't have enough reliable wind at my place.

But I have sun, I made two hot water panels for domestic hot water but do not have them on the house yet, I do have one on sawhorses for the last 4 months and the water in the tank has gotten up to 170.

You guys probably know of this site but I did not see it in your links.
http://otherpower.com/ they have quite a few homebrew turbines

[khalid]

Recently purchased a small satellite dish for making a parabolic solar concentrator. The idea was to take a feel of the heat it can generate and if found feasible then to expand it on..
I pasted 1 inch square mirror pieces with resin on the dish. It took more than 03 hours to mount hundreds of them. In the morning i just brought it into sun and viola in 03 seconds it started smoldering wood and other plastic things see picture3. It was a good start..
Some more experiment and temperature monitoring yet to be done. I shall check the maximum temperature attain on the focal point and will expand this topic here.

The initial results are very promising so far. I am surprised the abundant heat generation with this method. I am seriously thinking of using this heat.

I have an idea to make a bigger custom parabolic structure and mount flat mirrors on it (similar like first and second pictures..these pictures are not my work).Installation of two axes sun-tracking and mounting a small boiler at the focal point. Use the generated steam to run small turbine to generate electricity.

Oh really.. should i have to design the steam turbine and fabricate it? How much steam it shall require to generate at-least 500watts of electricity from the generator? How big the parabolic concentrator to give me continuous steam for running turbine?

Can i avoid generating electricity by using steam turbine? any other way to make electricity ?May be we able to make some simple system to harness this heat.. Thermodynamics is all about the temperature difference ;)

[ssflyer]

Hi Khalid,

Back in the 80's, I manufactured big fiberglass satellite dishes. I had a prototype model built, without any reflective material (used a carbon impregnated fiberglass, to reflect microwave) to test the mold.

I decided, "Why let it go to waste," so we set it up and applied aluminum foil to the surface. BTW, it was a 12' dish! WOW - you did NOT want to be anywhere near the focal point! I never measured the temperature at the focal point but I wouldn't be surprised if it would easily melt aluminum...

Anyway, back to some of your questions: I'd probably go with a piston steam engine as opposed to a turbine; cheaper and probably less pressure differential needed to operate.

Have you seen Zenman Energy's (http://www.zenmanenergy.org/solarSteamEngine.html) site on their ongoing efforts to make inexpensive solar power? Good read.

They like a pretty cool piston steam engine by Green Steam Engine (http://www.greensteamengine.com/products.htm) who sells plans for their 2 piston engine.

I also like Zenman's use of a trough type reflector, which only requires a single axis actuation.

[billp]

Could you somehow focus the parabola onto a Sterling engine?

[MogulTx]

The turbine is the best long term solution. The sterlings are notoriously inefficient and unreliable. They require a lot of maintenance. The turbine takes a lot of energy to wind them up , they dont take a lot of effort to keep them turnjng so you should be able to get them to turn out energy

[khalid]

@Ron,
I have gone through that site before..Their is steam engine seems to be good but i dont know how efficient will this be... I can't pay through paypal....I wish if i was able to order the engine plan with one flex shaft transmission...

What you did with 12ft version of solar dish?...

@Bill,
Stirling engine are pricy especially those that can output some sort of good work.

@MGM,
Turbine will be good but they make lot of noise during condensing and designing it will be pretty difficult..


Ron idea of using flex shaft steam engine seems to me good..but i have no engineering drawing to fabricate...
Any other idea?

[myxpykalix]

khalid,
this guy does a lot of videos on youtube, stuff you are trying to do, look up "green power science" or go to http://www.greenpowerscience.com/ and see if there isn't something there that might aid you.;)

[rb99]

Hi Khalid,

What site would you want to order the Sterling plan from?

How much are they?

Cheers,

Richard

[khalid]

Hi Khalid,

What site would you want to order the Sterling plan from?

How much are they?

Cheers,

Richard

Hi Richard,
Following is the website:
http://www.greensteamengine.com/products.htm

@Jack,
That was good website with lot of information and videos...

[ssflyer]

Richard,

They are an innovative piston steam engine - not sterling

[khalid]

Ron, are these positive displacement steam engine are really efficient? have you any experience with them?

[rb99]

Hi Richard,
Following is the website:
http://www.greensteamengine.com/products.htm



Those are the plans you want?

[khalid]

Those are the plans you want?
Richard, I need the plans and i shall make one to check how it behave with the solar concentrator steam. I shall post the progress update here..
I can pay you $45US for the plans via VISA card as i cant collect the plans from theiir site due to paypal service not available in my country.

[ssflyer]

Khalid,

I don't have any experience with that particular design, but I like the simplicity and really only simple tools are needed to construct one.

For low HP (like under 100), piston steam engines are actually more efficient than turbines, in my understanding.

Also add to that the fact that a turbine will require relatively expensive gearing to get the output down to a reasonable rpm.

The actual efficiency depends on a lot of factors; heat differential, condensing/recycling the steam, etc.

[khalid]

@Ron,
The Green Engine is not that stable after watching the actuall video.. It has lot of vibration...so i am not thinking to make it...The steam turbine are high RPM but we have many options..we can use high RPM generators..we can regulate the steam to run them at low RPM...
By the way..i am still in search of new ideas to work with...ma be we can invent some new innovative engine or solution...

@Richard,
Please do not order the plan.

[normand]

http://www.free-energy-info.co.uk/u might find some help here.
Good luck with the project!

[khalid]

Thank You Normand for informative website and greetings...
I have made the Axial Flux generator and for mounting the 6feet long blades i have to make a plate.Did some more work on my windmill. Attached pictures shows blade mounting plate and some fixtures for blades holding on plate.

I scanned the blade and then made the wooden fixture. In one of the picture you can see piece of blade fit on the wooden fixture.

[khalid]

WindMill was assembled and with a minor wind got it rotation at No load. Still needs wiring and improvement in other things..especially balancing of blades...

[khalid]

My son standing near the windmill.. Windmill rotataing at 5000RPS:D
................
Its rotating 10RPM or less but my camera shows like .........:eek:
My son is at very safe distance i swear...so don't warn me...;)

[jerry_stanek]

You should put a fence or something to keep someone from walking into the blades. I have seen pictures of small plane pilots that had a forgetful moment and that was their last one. I would hate to see that cute little guy hurt. kids have a habit of not paying attention when they are having fun.

[ssflyer]

Looking good Khalid!

Can't wait to see it finished and what the output is!