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Small Basic Project (solar panels to spin fans)

  1. Jul 6, 2012 #1

    I usually just lurk around the forums as a first year engineering student, but I'm 27 years old. I have my bachelor's in Accounting, but I'm not very passionate about it...anyway, that's a whole different thread, but the point i'm getting across here is that my practical knowledge of electronics is nil. I'm still fighting against Physics and Calculus and haven't been able to touch the real meat of engineering.

    Here's the situation, my son wants to put a fan in the dog house to keep our dog cool in the afternoon when we're away. While it's cute and adorable, it's probably pretty dangerous for the dog and may be more of a nuisance than a help for the dog.

    However, as a little project for us, I was thinking that we could link together some really cheap solar panels on the roof of the doghouse and then maybe a series of Case Fans from NewEgg.com.

    My questions are: What are the materials required for this project? Where can I get some really cheap solar panels that would provide sufficient power to create a slight breeze in a dog house? Are there any dangers I should be looking out for?

    I know this is pretty cheesey, but my son is 4 1/2 and I'd like to get him interested in STEM and this seems like a really cheap and safe way to get him started.
  2. jcsd
  3. Jul 6, 2012 #2


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  4. Jul 6, 2012 #3


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    Sounds like a fun project for dad and son :smile:

    But I think you will need a bigger solar panel than you think to make enough power for even a small fan. I recently bought one of those solar cell powered car window fans to try to keep my vehicle cooler in the sun, and the small panels on it would barely turn the fan even in direct strong sunlight.

    Do you know what kind of voltage & current the fans that you are looking at need? Start with those numbers, and look at what is available in hobby solar panels. And also factor in that you will not get direct sunlight most of the day (aiming the panels is a compromise). At least with a dog house (as opposed to a car), you can make a mast on top of the doghouse and aim the panels at the location of the sun for the hotest part of the day.
  5. Jul 6, 2012 #4


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    I have one on my boat. The whole thing is about 6" across and completely self-contained. They cost about $40.


    They're not meant to blow air, but they do keep it circulating.

    Buy one, take it apart to its component pieces and put it in a bag. Presto! You're got yourself a solar powered fan "kit", ready for father-son assembly! :biggrin:

    I can think of some other devices that might cool a doghouse.
    A thermocouple fan:
    A wind-powered fan:
  6. Jul 6, 2012 #5


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  7. Jul 6, 2012 #6


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    Added above. Or just Google marine solar fan.
  8. Jul 6, 2012 #7
    READ the specifications on the lables.

    Usual computer fan uses something like 0.5A or 500ma (or less) at 12V.

    IF it's a good NEW fan with ceramic bearings - that last 300,000 hours... (can be transferred from machine to machine - long after the dog goes) - you can run them on a very small solar cell - from 6V - 9V at 200 - 300ma (milliamps) - as an optimum...

    You don't need the full 12V or the full amperage, just has to be enough to run the fan fast enough, above the near stall speed... the power level that is around the point that the fan actually starts...

    I'd suggest a simple circuit - that has a NO (Normally Open) thermal switch inside the kennel that operates at say 30 - 35*C, a small solar cell - or cells, and one decent fan.

    It's pretty easy.....
  9. Jul 7, 2012 #8


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    You are one devious SOB, Dave. Merely one of the reason why I like you.
  10. Jul 7, 2012 #9
    I am torn between this idea and DaveC's devious idea, but DaveC's looks like it might be a bit more expensive than trying to do it with the base component parts first.

    Do you think it's possible to have this:

    powering one or more of these:

    Using common tools without too much electrical know-how?
    This project may end up teaching me more than it will teach him :blushing:

    Edit: Oh yeah, and the doghouse is like a funky log cabin looking rectangle, here it is:
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