[Peripherals] Electricity (was Re: The rest of the puzzle)

[info at olpc-peru.info]

Alternators:

Wind energy: low RPM alternators.  That is what you need.
Water energy: low RPM alternators, again.
Human (animal): low RPM alternators, the same....

All the alternators used in wind or water devices are low RPM (to the 
best of my knowledge... low RPM is around 600 RPM).

_*Option a)*_ 2nd hand alternators from trucks and old cars.
Alternators that come from cars and trucks are 3,000 RPM and more.  
Modification is needed.

You can modify the alternator (some models) to get lower RPM by doing this:
a) Adding more magnets (IF the structure of the alternator allow to add 
more magnets)  or...
b) Adding more wired copper coils... (IF the structure allows it).

Copper coil is available in Peru in many places, no problem.  Magnets 
ARE NOT available easily.  Some source for cheap magnets should be found.

2nd hand alternators can be found in many places in Peru at US$55 and 
up.  Reason: there is a huge market for 2nd hand car parts. 

My main concern is that for modifying a high RPM car alternator you need 
some extra skills and extra tools.

_*Option b)*_ 2nd hand alternators from small cars
Then we have low RPM alternators.  Unlucky we are that these alternators 
(and this kind of cars) have a huge demand in Peru (it doesnt matter if 
the car is 20 years old, it works and it will find a market).  So I have 
ask, a long time ago, and new alternators for this cars cost US$300 and 
2nd hand can be found from US$100 each.

So here we have them: 600 or 700 RPM alternators that are too expensive 
for the development of the solution.
_*
Option c)*_ Build your own alternator.

It is totally possible.  You only need magnets, coiled copper wires and 
some basic skills.  You can check how it is done by artisan methods.
The only "not available" part are the magnets (they should be imported 
from China).  Then a design and a plan could be delivered (with spare 
parts (mainly the magnets and the copper coil) to the town that will 
manufacture its own alternator by themselves. 

_*Option d)*_ Import your own low RPM alternators.  I have send email to 
some chinese manufacturer of low RPM alternators, without luck (because 
I think they are looking for bigger markets).

_*Option e)*_ Modify the design of the "mechanical" device, so... with 
the use of pulleys and other gadgets you can "amplify" the RPM that you 
need to work with a normal car or truck alternator (high RPM 
alternator).  This involves design of mechanics and physics laws that 
goes beyond my skills and that can be a burden for the humble peasants 
in the high mountains.  But any engineer will see as an "easy task".  I 
ask myself what difficulties can show up from the "improved design" due 
to heavy weights or more "pulleys" that need to be moved.  In this case 
we are "rebuilding" the origin of the industrial civilization (that 
comes from the use of one spinning wheel with human movement, to the use 
of 6 spinning wheels with the use of the very same human movement, then 
they took "running water" to move up to 120 spinning wheels (because 
human forces was not efficient), then they took steam and finally 
electricity to move 500 or more spinning wheels.  That was the start of 
the industrial revolution.  No problem to rebuild the whole process 
because these high Andes communities are tied exactly to the year 1821 
(that was the year of our "independence" from the Spaniard colonial 
power... the old Spaniards (due to his economy system) keep "updated" 
those communities with the last customes and uses that were normal in 
those year, it is the "republic" that forgot that these communities 
exist and you can find them in the same (or worse) conditions that they 
had in 1821).

_*Option f)*_ There are some low RPM alternators that are used for 
industrial purposes.  I ask about them here in Peru, but the cost is 
US$700 and up.

Finally, a human been (treadling or pedaling) in a normal spinning wheel 
can produce around 500 RPM.  I have not calculated how much RPM can be 
produced in a bicycle, but the problem with bicycles is that you are 
moving the whole leg, then you are "wasting" too much energy and you can 
not sustain the movement by a long time.

Other info: I have found that you need 600 RPM devices to keep the whole 
thing in a realistic enviroment.  It is possible to get energy from 
lower RPM but then you have to add too many magnets and too much copper 
wired coils and the weight of the "turning wheel" increase and the price 
of the components increase.  The best of my experience tell me that 600 
RPM is what we need to look for.

I hope it helps.

Javier Rodriguez
Lima, Peru


> Javier, please find out what used alternators go for from junkyards in
> Perú. Here is one other data point. "The cost of a Delco CS-130
> alternator at any US junkyard should be $10.00 to $15.00 US."
> http://bernardembden.com/xjs/altmove/index.htm
>
> When I ask you whether it is better to curse the darkness or to teach
> people to make candles, I don't want to hear you grumbling about the
> lack of candle-making materials. If we don't have candlewax, we will
> make oil lamps or coal fires or something. I just want a direct answer
> to the question. Are you in or out? Are you ready to work toward
> solutions, or not? OK?
>   
> ------------------------------------------------------------------------
>
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