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Small Solar panel(s) with output equivalent to a good USP port Answered

Hello all,

Seems like this should be a good competition type project.  Being a hiker and bicycle traveler, I would love to have a small, (read lite), solar panel that would keep my electronics powered up.  The electronics would be, a phone, front and rear light or headlamp, a small 7" tablet, and maybe a small mp3 player.  Ideally the output would equal that of a good USB port, 5volt and ~2amps.  The charger for tablet states 2.1amps.  Sorry I'm not dialed in what ideal amperage would be, but I do know that not less than 2amps, right?

Anyways would love to see a competition among the peeps all dialed into this with the parameters stated above.  I'm sure other parameters would be worked out too. 

If there's something out there in the real world that maybe you think would suit my needs, lets see what there is out there!  Feel free to post up.


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6 years ago

I agree here, commercial products as well as projects and homemade solutions already exists for this like sand on the beach.

It can be put down to quite simple maths:
5v @ 2A equals 10W of power.

This means you will need a solar panel capable of producing at least 12W (for the losses in cables and electronics, plus a little reserve) in cloudy weather.

For that reason and because you will never be able to keep a perfect alignment of the panel during rides or hiking trips, the solar panel must be quite a bit bigger than the minimum.
Since most panels work at 12V and up to 48V for the bigger ones you are lost to finding a panel setup that provides what you need.

Sure you can add many small panels to get to about 7V, use a step down converter for bigger panels and so on, but it all comes down to the 10W in bad conditions.

Problem is not the electronics, but the power supply for them.

On the bike it would be easier and more efficient to use a generator driven by the wheel or chain.

For hiking maybe a cover with solar panel for the backpack or a bigger panel in a fold up type that also acts as a sun shape over your head.


6 years ago

There are quite literally hundreds of products like what your looking for. Pocket sized batteries with built in solar panels. That can provide 5V via a couple of USB ports a@ up to 3A.

Here is a review of one such product.