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    Newb needs help

    I'm trying to setup a solar powered wifi camera. That is, I can find the camera, and it's powered by a USB port. Does anybody know if those things might use anything like the full power from a USB port? I need to know so I can properly size a battery, solar panel, and charge controller.

    Being new to this, i don't know if i've done this right, but it seems like i'd need a bigger panel and battery than i wanted (size is a problem) for this project.

    If anybody is willing to partake, here's my notes so far:

    Any camera which can run off USB power, will at maximum, consume the following:

    500mA * 5 Volts = 2.5 Watts,

    2.5 Watts * 24 Hours = 60 Watts.
    And
    500mA * 24 hours = 12,000 mAh of power if run from a battery all day.
    Multiply by 2 to allow for never drawing the battery below 50% charge, we need a 24 Ah battery.

    So, if we say we will get some sun everyday, but have enough battery for 24 hours, we should be in good shape.

    We'll just need a 24 AmpHour battery
    A Solar panel which can provide 60 Watts over the sunny period. 60 Watts div. by 5 hours = 12 Watts panel, is the minimum size, up to double that would be fine..

    A a charge controller for the Solar panel to feed the battery,


    If it will fit in a bird house sized box, we're good. Just need a sunny location with a southern sky exposure.

    Panels: 70 miliwatts per square inch., x 5 hours, = 350 Milliwatts hours per square inch per day.

    1 square foot is 144 square inches, or 50.4 watts per "day."

    Charge controller calcs:
    12 Watt Panel / 12 Volts = 1 Amp, add safety factor makes int 1.25 Amps Array Short Circuit Current (minimum controller input current)
    Max DC load current = 2.5 Watts / 5 volts = .5 Amps. (Minimum Controller output current)

    If we double the panel we need a 24 watt / 12 volts * 1.25 = 2.5 Amps for the array short circuit current and
    The max DC load doesn't change. So, total is No larger than 2.5 Amp controller.

    Of course, this all may be moot - the camera probably doesn't draw anywhere near the full power of the USB port.

    #2
    are you planning to build this yourself? because there are commercial solutions that aren't very expensive that might fit your requirements already.

    google for solar monkey.

    I've been foolishly trying to solar power my quadcopter for perpetual flight lol....
    That obviously isn't going to work.... multirotors are just so bloody inefficient compared to planes so I figured maybe I'll try an ultra-tweaked glider instead....

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