[Peripherals] Alternitive Power for Developing Countries

Thu May 8 02:30:54 EDT 2008

On Tue, May 6, 2008 at 11:24 PM, info at olpc-peru.info
<info at olpc-peru.info> wrote:
>
>  Hello Arjun et al,
>
>
> >* Cost of Alternators -- I agree they are expensive. Have you thought
> about taking car alternators?
>
> You need to choose those alternators that have low RPM (low Revolutions Per
> Minute).

But we can do gearing/reduction for alternators with high rpm. But I
would agree that low RPM alternators would of course be much easier.
However I haven't been able to find any such easily. Copying the India
list if people might have some suggestions

>
>
> >They give 12V and usually have built in
> mechanisms for cut-off when the battery is fully charged, and also
> would be easily available.
>
> Yes, easilty available. In Peru that means that, but it doesnt mean that
> they have a low cost. The most popular car here is the Korean "Tico". Is
> everywhere, but... unlike we are... there is such demand that the alternator
> (new one) cost US$300 each one.
>
> It is not possible to think in a solution based on "second hand"
> alternators... they work.. but how we will get 250,000 used alternators for
> the 250,000 XOs that will be deployed in Peru ? We need to develop
> prototype, pilots that can be "sourced" in a secure, stable, confident way.
> Wars have been lost due to the failure on the supplies chain.
>

I am thinking that cost factors might make it better to build a setup
that has an alternator to charge more than one laptops (say 5-10) at
one time. Agreed, the mechanical setup might be more elaborate but it
_might_ just work better.

I of course agree, that second hand alternators is not a good path to take.

>
> >In India I've found car alternators to cost
> ~$100. They give about 35A output.
>
> Maybe we will need to import them. But... who will finance this ? We can do
> the pilot/experiment/test/initial design. But... what then?
>
> >... I have come to realize
> that it is very difficult for a human to provide the mechanical power
> needed to charge an XO, whatever they may use - legs/hands etc. This
> was one of the reasons why we fundamentally wanted animals to drive
> our solution and not be human powered.
>
> That is because we are thinking in using ANY alternator. Normal car
> alternators (like a Toyota) need 3,000 RPM. Then you need to "pedal" (on the
> bike) very fast and very steady to reach those RPM that the alternator needs
> to start to generate energy. IF you use a LOW RMP alternator then you don't
> need so much mechanical movement. There are alternators (here in Peru) that
> works at very low RPM, just 200 RMP and they are generating huge energy,
> they are used for some mining equipment and they cost around US$800 each.
> So, technically is possible to "break" the RMP barrier, but then money is an
> "impossible" wall to climb.
>
> There are many answers to this dilemma:
> a) Modify a car alternator: add more magnets, add more "cooper" coiled
> parts. Then you will need less RPM. You will need to do this with almost ALL
> the car alternators that you can find. If you get an alternator that is on
> the 600 RMP then you are VERY NEAR to what any human been (big or small,
> child, woman, man) can generate.
> b) Build your own alternator: import the magnets from China, very very (and
> very) cheap. Locally (at least in my country) we can add the cooper coils
> bobins. We need a good design and some testing. Add some circuits (very
> cheap too, any medium skilled tech here can build one) for doing the cut
> off, the rectification, and other electronic gadgets.
>
> More: the bike/leg combination is not usefull because you move THE WHOLE
> LEG. Too much waste. Then you transfer all that spend energy to a small
> "flywheel" that transfer (by the chain) the movement to the rotor (that is
> in the back of the bike). You need to do this because you need BIG torque
> (initial force). In the case of the "charging batteries" there is not need
> to move the weight of any person so no such a need torque is needed. So, IF
> you use a spinning wheel (that is what I have in mind) you move just one
> foot and that is good enough to move a BIG wheel that will move the "rotor"
> on the alternator (or the pulley on the alternator). I have done the
> calculations and that "foot" movement can generate from 500 to 600 RPM with
> a very low and normal "pedaling" (treadling) rhythm. Since it is in the
> "border line" I think we would need to add some extra pulley system to add a
> little bit more RPMs.
>

I like the spinning wheel idea.

>
> >*Rule of thumb -- Whatever you may design, remember, as a simple rule
> of thumb, that from the alternator you may use, you'd need to provide
> each XO laptop about 1.5A of current at 12V for about 2hours to charge
> the battery from empty to full.
>
> I am taking note. Question: how long can the XO work with a full charged
> battery ?
> (then we can calculate how many "alternator sets" we need for this or that
> school)
>
> >It would be my suggestion to plan out the
> power solution as much as in detail as possible before implementing
> it, it would save you problems that you might face later on!
>
> AMEN!!!! Base line is what we need.
>
> Javier Rodriguez
> Lima, Peru
>
>
>
>
>  Arjun Sarwal wrote:
>  Hi Javier, Caryl and others,
>
> A few thoughts.
>
> * Cost of Alternators -- I agree they are expensive. Have you thought
> about taking car alternators? They give 12V and usually have built in
> mechanisms for cut-off when the battery is fully charged, and also
> would be easily available. In India I've found car alternators to cost
> ~$100. They give about 35A output.
>
> * I would like to see more variations of human power being explored,
> like the one Caryl has mentioned. I think it is a very interesting
> idea. However, whatever experience I have had, I have come to realize
> that it is very difficult for a human to provide the mechanical power
> needed to charge an XO, whatever they may use - legs/hands etc. This
> was one of the reasons why we fundamentally wanted animals to drive
> our solution and not be human powered.
>
> * Bicycle - Holden Bonwit, cced here was recently working on Bicycle
> powered solution at a place near Delhi. I will fish for the link he
> sent me, but they concluded that it is difficult to get enough output
> from a single dynamo to be able charge XOs
>
> * Battery -- In terms of electrical design it'd be much better to
> charge, say a 12V car battery or something rather than directly
> charging the XOs. This would basically save us hassles of having to
> put a current limiting circuit, and also car batteries or other Lead
> Acid batteries can be charged with variable current, for example they
> can sometimes get charged much faster when higher current is
> available, but the range of current the XOs can take for charging is
> limited. But we can get to specifics about electrical design etc later
> on.
>
>
>
> *Rule of thumb -- Whatever you may design, remember, as a simple rule
> of thumb, that from the alternator you may use, you'd need to provide
> each XO laptop about 1.5A of current at 12V for about 2hours to charge
> the battery from empty to full.
>
>
> I hope these help in some way. Please let me know if I can provide any
> other useful information. It would be my suggestion to plan out the
> power solution as much as in detail as possible before implementing
> it, it would save you problems that you might face later on!
>
>
> best regards
> Arjun
>
>
>
>  Message: 2
> Date: Mon, 05 May 2008 14:05:32 -0400
> From: "info at olpc-peru.info" <info at olpc-peru.info>
> Subject: Re: [Peripherals] [support-gang] Alternitive Power for
>  Developing Countries
> To: Mel Chua <mel at melchua.com>
> Cc: Yama Ploskonka <yama at netoso.com>, peripherals at lists.laptop.org,
>  "Community Support Volunteers -- who help respond to \"help AT
>  laptop.org\"" <support-gang at lists.laptop.org>
> Message-ID: <481F4C6C.7010604 at olpc-peru.info>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> Hello Mel and all the people on the peripherals list,
>
> I have been discussing the issue of energy with other fellow on the OLPC.
>
> I am honest and I speak directly all the time: I think the solar energy
> is not a realistic posibilitie in Peru: there is 100% sunny days in the
> Andes JUST 6 months in a whole year. The worst moments are the 4 to 5
> months were some villages (located over the 3,500 meters altitude) get
> 100% cloudy time, very cloudy, huge rainfall. According to all the
> investigation that I have done (I can send to anyone if you are
> interested) the solar devices can provide from 5% to 20% IF there is not
> a sunny day. That is a BIG problem.
>
> My best understanding, based on previous experience when I have work for
> a mining company is to build a mechanical device: human driven, leg
> driven. But not a bycecle. We have built it before but it was without
> "cost" restrictions. It is based on a spinning wheel (I have many here
> at my sight). But when I have put "cost" as a variable to take in
> account then I have got the next ideas:
>
> a) Using alternators, in Peru, is expensive. Each alternator cost
> US$300 aprox.
> b) We need to import some magnets and assembly the alternator by
> ourselves. The kids on the villages can do it as part of the
> "experience". We must provide the alternators, the copper wire, the
> circuit and components for the rectifier, and... the battery (battery is
> other hard issue... short live... expensive). Assembly this "home made"
> alternator, connecting to the spinning wheel (that can need a double
> wheel or a "pulley" chain) can be an improvement (according to the first
> results that we can get).
> c) Legs are the ones that will be used. Not in a bycecle but on a
> spinning wheel. It is totally possible generate enough energy for a
> regular laptor with the legs, it will be easier for the XOs. Providing
> energy for the XServers is a totally different issue, I don't agree with
> the use of XServers. I suggest that one of the XOs MUST behave as a
> Server (or the whole local XO network should behave as a "shared server"
> sharing processing power... but that is a bigger task).
> d) Need more energy? Put bigger magnets or "more" copper wire. Too
> heavy to move? Change design: move the copper wire around the magnets.
> Too heavy yet? Use concatenated pulleys.
> e) Cost?: import the magnets from Korea or other asian manufacturer.
>
> In this moment I don't have the time to develop this pilots (because I
> work independently, earning bread and butter for daily living, as
> anyone, and my spare time is not good enough to attack the problem in an
> efficient way). So I am passing this info to you (and I can discuss and
> help more if there is someone interested in develop this prototypes).
>
> If we don't get an asnwer for the energy problem then we will be
> delivering (we ARE delivering) XOs to the towns and villages that "look"
> poor in the eyes of the occidental culture but we are forgetting that in
> Peru the deep poverty is located in those 80,000 villages (5 million
> people) with less than 100 families in each villages, without
> electricity, less than FIVE HUNDRED dollars as total ANNUAL income for
> the family (with the work of the father, mother and children from 6
> years old). The goverment can not reach them (they reach JUST the 5,000
> other villages that contains the rest of the peruvian population, 23
> million people). So IF we deliver XOs just to the towns that HAVE
> electricity then we are keeping a "STATUS QUO" that have kept the same
> since 1821 (our "independence day" from the old spaniards conquerors).
> We need to be part of the solution and not be part of the problem.
>
> We will develop this "energy" gadget (this or other one!) and then ALL
> the responsible people will be more than happy to bring the XOs to those
> villages. Then we, all, be very happy. Until then the "One Laptop Per
> Children" will not be a dream.
>
> Best regards,
>
> Javier Rodriguez
> Lima, Peru
>
> (just for the record: my other two nightmares are: internet connection
> without any VSAT (or paying to the telephone company)... building
> something like UUCP or a UUCP revival... and content, content, content).
>
>
> Mel Chua wrote:
>
>
>  Moving discussion to "peripherals" list (please reply to
> peripherals at lists.laptop.org - subscription info at
> http://lists.laptop.org/listinfo/peripherals)...
>
> Chris Carrick, one of the staff members for the grassroots office in
> Chicago this summer (our resident mechanical engineer & green guy), will
> be working on getting many "ideas with prototypes built and tested" as
> well as "simple instructions for replicating them made available to
> empower the folks to generate their own power." (More of a "here's how
> to design your *own* power solutions!" in the end, even more than a
> "copy ours!" resource.) So your wish will be granted, Caryl. :)
>
> -Mel
>
> Caryl Bigenho wrote:
>
>
>
>  Yes, I thought of that too. But who would ride the bike? Where would
> they go? Would it be an exercise bike? Do these folks really need more
> exercise? If they, or someone in the family, will be riding around
> anyway, it would work. But if they are walking most places (as the
> folks in the Andes tend to do), the bicycle is not a luxury they have at
> hand. Still in some places it would probably be a great idea.
>
> I would love to see lots of ideas with prototypes built and tested and
> simple instructions for replicating them made available to empower the
> folks to generate their own power. Call it "Power Empowerment!"
>
>  > From: akonstam at sbcglobal.net
>  > To: support-gang at lists.laptop.org
>  > Date: Sun, 4 May 2008 14:40:55 -0500
>  > Subject: Re: [support-gang] Alternitive Power for Developing Countries
>  >
>  > On Sun, 2008-05-04 at 08:26 -0700, Caryl Bigenho wrote:
>  > > Hi...
>  > >
>  > > Yes, I've seen that weza treadle. The price is way to high for
>  > > developing countries...it costs more than the XO! I'm looking for a
>  > > charger that can be made inexpensively from something that may be
>  > > readily available. It might even be possible to retrofit one of the
>  > > sewing machines so it could sew and charge at the same time. That way
>  > > Mom could recharge Junior's XO while she was making clothes or
>  > > whatever!
>  > >
>  > > I wil take a look a the other list and move this idea there later this
>  > > morning.
>  > >
>  > > Caryl
>  > I am sure someone has thought of this but a bicycle would make an ideal
>  > charging device.
>  > --
>  > =======================================================================
>  > Romance, like alcohol, should be enjoyed, but should not be allowed to
>  > become necessary. -- Edgar Friedenberg
>  > =======================================================================
>  > Aaron Konstam telephone: (210) 656-0355 e-mail: akonstam at sbcglobal.net
>  >
>  > _______________________________________________
>  > support-gang mailing list
>  > support-gang at lists.laptop.org
>  > http://lists.laptop.org/listinfo/support-gang
>
>
> ------------------------------------------------------------------------
>
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>
>
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>
>
>
>
>
> ------------------------------
>
> Message: 3
> Date: Mon, 5 May 2008 14:35:57 -0700
> From: Caryl Bigenho <cbigenho at hotmail.com>
> Subject: [Peripherals] Alternitive Power for Developing Countries
> To: <info at olpc-peru.info>, <peripherals at lists.laptop.org>
> Message-ID: <BLU108-W40798E83494CA5CAB3D780CCD70 at phx.gbl>
> Content-Type: text/plain; charset="iso-8859-1"
>
>
> Hello Javier Rodriguez and, all the other folks on the peripherals list,
>
> After seeing the creative things Arjun Sarwal is doing with cow-power in
> India, I started thinking of other possibilities. I remembered my
> grandmother's old treadle sewing machine and how excited she was to have it
> electrified. Later, I saw many being used 35 years ago in regions in the
> Yucatan where there was no electricity.
>
> Here is a link to a picture of what they look like. It is the one on the
> left.
>
> http://www.sil.si.edu/DigitalCollections/Trade%2DLiterature/Sewing%2DMachines/
>
> Many of these machines still exist. i see them at estate auctions every
> summer in Montana. There must be thousands throughout the world. I have
> twice tried bidding on just the treadle mechanism of one on ebay. I lost out
> on the bidding for both, but have hopes of finding one in Montana this
> summer.
>
> When I get one, I intend to try to set it up as a combination desk/power
> source to run an XO. If it works and doesn't cost too much to set up, it
> might be something that could be replicated all over the world where these
> old machines still exist...some probably still being used without
> electricity.
>
> Javier, have you seen any of these machines in rural Peru? Are they still
> being used to sew? Would there be a need to try to design it to continue to
> be used as a sewing machine but to generate power at the same time?
>
> It might also be possible to manufacture a similar mechanism, at a modest
> cost. But, the idea of recycling the old ones has a lot of appeal. I was
> also wondering if an old automobile generator could be adapted to work with
> it. Perhaps it would require too much torque to work.
>
> It may be just a crazy idea, but if cow-power works, maybe this will too. If
> and when I do this project, I will probably need some advice from you folks.
> Any suggestions for starters?
>
> Caryl
>
> BTW, Could AJ's Cow-power generator be adapted to run on Llama power? How
> about donkey power? Goat power?
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>
> Message: 4
> Date: Mon, 5 May 2008 23:30:06 +0000
> From: "Alfonso de la Guarda" <alfonsodg at gmail.com>
> Subject: Re: [Peripherals] Alternitive Power for Developing Countries
> To: "Caryl Bigenho" <cbigenho at hotmail.com>
> Cc: peripherals at lists.laptop.org
> Message-ID:
>  <ed60564a0805051630t5deb641ap825b2b17c65495c8 at mail.gmail.com>
> Content-Type: text/plain; charset="iso-8859-1"
>
> Hello,
>
> In the COS (www.cos-la.org), we are working some months ago in some options
> for that, specially with a portable solar panel trying to reduce their cost
> (about 60 dollars each). The device -commercially available as cell
> charger- is really small and can charge the XO without any problems. In a
> field test in Junin and Arahuay (Per?) the panels works great, in fact, in
> the recent event of FLISOL in Huancayo (Junin-Peru) for the OLPC project, we
> test the solution (commercial) between 3400 mts and 4500 mts (Ticlio).
> Antonio Ramirez, Carlos Reinoso and who writes now are working in our breaks
> on this task (reduce the cost for about 25 dollars each).
>
>
>
>
> 2008/5/5 Caryl Bigenho <cbigenho at hotmail.com>:
>
>
>
>  Hello Javier Rodriguez and, all the other folks on the peripherals list,
>
> After seeing the creative things Arjun Sarwal is doing with cow-power in
> India, I started thinking of other possibilities. I remembered my
> grandmother's old treadle sewing machine and how excited she was to have it
> electrified. Later, I saw many being used 35 years ago in regions in the
> Yucatan where there was no electricity.
>
> Here is a link to a picture of what they look like. It is the one on the
> left.
>
>
> http://www.sil.si.edu/DigitalCollections/Trade%2DLiterature/Sewing%2DMachines/
>
> Many of these machines still exist. i see them at estate auctions every
> summer in Montana. There must be thousands throughout the world. I have
> twice tried bidding on just the treadle mechanism of one on ebay. I lost out
> on the bidding for both, but have hopes of finding one in Montana this
> summer.
>
> When I get one, I intend to try to set it up as a combination desk/power
> source to run an XO. If it works and doesn't cost too much to set up, it
> might be something that could be replicated all over the world where these
> old machines still exist...some probably still being used without
> electricity.
>
> Javier, have you seen any of these machines in rural Peru? Are they still
> being used to sew? Would there be a need to try to design it to continue to
> be used as a sewing machine but to generate power at the same time?
>
> It might also be possible to manufacture a similar mechanism, at a modest
> cost. But, the idea of recycling the old ones has a lot of appeal. I was
> also wondering if an old automobile generator could be adapted to work with
> it. Perhaps it would require too much torque to work.
>
> It may be just a crazy idea, but if cow-power works, maybe this will too.
> If and when I do this project, I will probably need some advice from you
> folks. Any suggestions for starters?
>
> Caryl
>
> BTW, Could AJ's Cow-power generator be adapted to run on Llama power? How
> about donkey power? Goat power?
>
> _______________________________________________
> Peripherals mailing list
> Peripherals at lists.laptop.org
> http://lists.laptop.org/listinfo/peripherals
>
>
>
>  --
>
> --------------------------------
> Alfonso de la Guarda
> COS
> www.cos-la.org
> www.delaguarda.info
> Telef. 97550914
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>
> End of Peripherals Digest, Vol 6, Issue 3
> *****************************************
>
>
>
>
>
>
>

-- 
Arjun Sarwal
http://dev.laptop.org/~arjs