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PA5COR
12-31-2010, 09:49 AM
I was asked to write down my experiments in alternative energy, so here it goes...

I'm not an expert, just the happy tinkerer that finds some stuff and tries to make something from that i can benefit from, or just have fun in making it work.

Solar cells, i got a batch for almost free, end of production line remnants from Phillips, i bet if you look around or Google it, you can come up with sources in the USA that deliver them cheap also.
Production panels mostly are expensive, these cells ( end of production, end of sale etc) can be had for scraps.
Having the same milli Amperage, you can couple these cells up to any voltage you need, or doubl the Amperage whatever your need or choice.

Done so far:
Used an old generator from an car ( 75 Amp) some pullys 1:4 and a home made wind generator, making blades from PVC tubing cutting them so, that blades came out, 2.8 meter total diameter, 5 blades.

Since the windgenerator head will not turn fast enough to get the generator working fast enough add the pully's and v belt to up the revs 4 times or more, depending on your needed speed for the generator to work reliable.

In the modern car generators is the rectifier and voltage regulator already build in to charge an old car battery or better deep cycle marine battery.
Never run a generator without load......it will run away in speed and self destroy....

Put it high above any restriction, houses, trees etc, higher = more wind = more energy.
You can get sinus inverters 12 volts to 110 or for me 230 volts 50 Hz.
I had a spare one for 500 watts continuous, after my tests were done i sold this contraption to a farmer 3 years back and he stil uses it for supplying light and using small electric tools in a shed far from the grid.

You can start with small generators using electric motors as generators, and go from there.
Some commercial generators can be had, even relative cheap.
http://www.allsmallwindturbines.com/
Large list there, read some of the PDF files for instruction manuals, and tips.
Most of these turbines come with electronics charging circuitry etc.

Solar cells.

Depends on what you can get make an array that delivers at least 19 volts free running without load.
Use a Schottky diode for reverse polarity protection.
You can get relative cheap solar cell voltage regulators that will take the energy from the cells and that will charge a battery ( 12 volt)

For the homebrewer there are special I.C's that will do the job, with some external components they will do the same, when i started these weren't there, now they are available.

When you use the generator or the solar cells, the best way is to make your alternative supply from a combo, wind and solar energy.
No wind, there will be daylight to charge the battery, no sun, there will be wind at night to charge the battery.

I'll start a small turbine project this year with just a 1 meter diameter fan.
An old Papst 50 watt 12 volt DC motor will be the generator.
With the right revolutions it developes 18 volts DC followed by a Schottky diode for 5 amps ( just 0.15 volts voltage drop) for reverse voltaage protection and a homebrew loading circuit for the battery and dummy load for if the battery is full to ballast the generator.

So far my first part.
piccie of the used solar cells mounted on stainless steel plate.
Your comments please ;)

ki4itv
12-31-2010, 10:05 AM
Sad to say, but this was my first foray into solar power for executing a mundane, yet necessary repetitive task.

It competently wags The Finger at the neighbors from sunrise to sunset...
Saves our family a lot time to do other things. :lol:


Not quite as cool as yours COR.

N1LAF
12-31-2010, 10:07 AM
Was the car alternator practical? I didn't even think about alternator RPM.

PA5COR
12-31-2010, 10:07 AM
Part 2.
http://www.mdpub.com/Wind_Turbine/
Working plan with picccies for homebrew wind generator.
Including electronics schematic diagram for the controler, do scroll down for the latest version.

http://www.metacafe.com/watch/1782153/how_to_build_a_home_made_wind_generator/
Video of cheap homebrew generator, using a standard scrap car generator.

http://www.thekevdog.com/projects/wind_generator/
Same, including piccies of how to make the blades.

http://www.otherpower.com/otherpower_wind_alternators.html
Some generator motors to use

N1LAF
12-31-2010, 10:17 AM
The link to http://www.mdpub.com/Wind_Turbine/ is Excellent!! Great Link!!

Real schematics, practical experience, and easier than expected to construct, using cut PVC pipe for blades...

PA5COR
12-31-2010, 10:32 AM
The car alternator was cheap.....
But it needs fast RPM, so that was why i needed the pully's and v belt to a 1:4 speed up...
Better are the old homemade permanent magnet alternators, needing lots of work to do yourself, but these are the dogs danglies. ;)
Old induction motors if you can get them, good for low speeds, for low power levels. 10 - 25 Amp output...
DC motors, that is where i play the most with, easy to get, cheap, (old tape drive motors) 100 - 200 watt output.
Remember 24 hours of 100 watts is 2.4 KW power...

PVC pipe cut blades are the easiest way to make them, if you have an angle grinder at slow speed, it'll be fast ;)

http://alton-moore.net/wind_calculations.html
Alton's Propeller Carving And Power Calculator

mw0uzo
12-31-2010, 03:17 PM
Thanks for sharing - another project to add to the list :)

kb2crk
12-31-2010, 06:13 PM
definatly a good project to try. i have a 100 amp alternator that needs a new rectifier. that would make a good starting point.
i also have one of the el cheepo power regulators for charging from solar panels along with an old but good 12v ups battery. i may have to get back into working on these projects as they have stagnated for some time...

W2NAP
01-02-2011, 01:37 PM
nice info.

Ive thought about building a wind turbine last year.. just never got around to it.

W5GA
01-03-2011, 04:54 PM
Anybody know what the efficiency of one of these inverters is?

PA5COR
01-03-2011, 06:21 PM
Good inverters can have a high efficiency, switched mode inverters are lots more efficient as the old linear type.
You need good decoupling sms's for us Ham's... but it can be done.
If you want to use an old car generator, for lots better efficiency you shoud rewind the coils with different coils, thinner wire and lots more windings, that will boost the efficiency at low rev's.

In the links you will find pointers and sources for the other electric motors that are better suited.

You can make a set up for 100 - 150 dollars and keep a large battery loaded used for all kind of tasks, if you get a 200 - 500 watt generator and live in a place with decent amounts of wind, you can cut costs in your use.
Make it an average 12 out of 24 hour generation for a 500 watt generator, that would yield 6 kW energy.
Add some inverter/battery losses and stick with 5 kW to be used, daily.

Add some solar cells, when there's no wind, there will be sun, or both.