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Electricity for poor communities

  1. Jun 23, 2009 #1
    Sorry if the subjetc is not at the good place.
    My project is to provide electricity at poor communities in Kenya. They don't have electricity and I would like provide electricity for light just with a battery and a switch> So I need to find a box with battery and a switch and I suppose it exist. It is possible to find a switch who works maybe with three colours, green its ok, orange your battery is almost empty and red is no more electricity. And the switch could permit to give lectricity during 30min and the light will be stop after that and you have to push on the button after to provide electricity.

    I can recharge the battery with a source near the village. What do you think about it?
    Because all my research give me a lot of things very complicated like PV pannels or others....

    Thank you
  2. jcsd
  3. Jun 24, 2009 #2
    Thank you for your help it's a pleasure
  4. Jun 24, 2009 #3


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    I'm not sure what you need.
    You can charge the battery near the village, do you need the design to supply 12 volts ? or do you need 12 volts stepped up to 120 volts?

    Are the lights in the village, already in place or will they be part of the box assembly ?

    How much light and how many 30min cycles will be needed ?

    Please give a little more info.


    P.S. what kind of budget do you have for your project ?
  5. Jun 24, 2009 #4
    Its for poor communities in Keny, for 100 houses. So I want to make simple project, to give them light with batterie. One light is enough I think, I just want to know if you think that one LED at 3W is enough for one small house and if the LED diffuse the light decently.

    And I need a regulator with a switch to cut the power every 30min just if the people forgot to switch off the light. And something to see if the battery is almost empty or not.
    We can recharge the batterie in an other place so we want to create a job. The man would have the possibility to earn money if he recharge the battery every weeks.

    There is nothing in the village I want to make this process in all the houses. So I need something that is not expensive because we have to do this for 100 houses.
  6. Jun 24, 2009 #5


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    A bathroom rotary timer would work: http://www.bathroomfanexperts.com/product.php?p=fantech_97030-w&product=112150&category=1706
    But dreadfully expensive at $25 each

    Or you could build your own 555 timer circuit: http://www.hobbyprojects.com/timing_timer_circuits/5_ to_30_minute_timer_circuit.html
    I don't see a need for this. The lights will dim when the battery is near empty. Though if you are using a lead acid battery, you shouldn't run it below 50%. I would recharge the battery daily.

    Just one battery for 100 homes? At 3 watts each? That's 300 watts if everyone is up partying. Is this going to be a huge battery?

    I estimate it will cost somewhere between $1000 and $3000 for what you want. But there are many variables we do not know, so it is difficult to say for sure.

    ps. PV panels are not anywhere near as complicated as rocket science.


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  7. Jul 17, 2009 #6
    Sounds like a lot of trouble for not enough benefit. 3 watts seems hardly enough to be very useful for a non-mobile light, and yet 300 watts seems a bit much for the battery, especially once it's strung out all over the village over a great deal of wire (D.C.'s not so good for power transmission, that's why they invented D.C.), and having the whole system depending on this one battery (which may be a security problem) seems a bit brittle of a solution.

    Wouldn't it be better if they each got one of those electric lanterns with the built in hand-cranked generator (some use solar, as well)? They could be had for about $30 each, nobody would be dependent on anyone else lugging the battery in every day to recharge. No ugly transmission wires (which would be subject to damage), and best of all it's mobile. It would be power on demand--if you need some light and the battery is down or low, just give it a good crank and you're in business! Example below.

    Here's one designed for camping/the outdoors, has a handy foldaway hook and adjustable reflector, is also solar-powered--10 hrs sun = 6 hrs light, 1 min. cranking yields 30 mins. light, and can also be charged from a 12 volt charger.

    (Of course there are many other models to choose from.)

    http://www.preparedness.com/sotatopsohal.html [Broken]

    If you write the company (write to ten different ones, maybe), you might get some donated for your cause if you play it right. Just a suggestion.

    Last edited by a moderator: May 4, 2017
  8. Aug 18, 2009 #7


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    This thread may be a little old now, so I'm not sure if the OP is still around.

    I don't know about enough power for 100 houses. When I recently visited Mozambique, one of the rural clinics was running entirely on solar power. I think part of the trick was having light colored walls that reflected a lot of light so even small amounts of light seemed like a lot. They had 4 solar panels, I have no idea what the wiring pattern was (I wouldn't have a clue what I was looking at even if they showed me). During the day, they ran about 6 computers in their various clinic buildings, and lights in the clinics. Most every place else, they just used ambient light through the windows. At night, I'm not sure if the two dormitories at the mission were lit (one for boys and one for girls), but the monastery with the kitchen and guest rooms was lit, along with an adjacent building that has a classroom with 7 computers (for HIV/AIDS education...still being set up so not operational yet when I was there). Of course, the lights were not left on continuously, just whichever rooms were occupied (we primarily gathered in a dining room adjacent to the kitchen). All of the computers and lights were designed to run off the stored solar power...I don't know where they got them, but they were "off the shelf" equipment, nothing custom designed as that would have been too expensive. Even so, once it was nightfall and everything was on stored power only, even conserving to really only have lights on in one room, we barely got through dinner before the lights went out (clearing the dishes was done by flashlight and candles), as was getting ourselves ready for bed.

    Of course, at the mission, they really aren't so worried about having lights on at night...that's more a luxury to use lights rather than candles...it's more that they can run computers during the day in their health clinics to keep records and track statistics, as well as access the internet for communicating with the provincial hospital where they send samples for lab tests they can't perform on site. They also need the lights in the maternity ward for night deliveries.

    You might want to consider a similar idea. Instead of trying to provide everyone with some short amount of electricity at night, which they could do without, perhaps focus on getting PV cells to provide electricity during the daytime at a community center where they can access computers for things like lessons or communications, or just to recharge cell phones if there is cell service out there.
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