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This is not a review of that nifty little solar panel I received as a "ATTA BOY" from work but rather what I found out when testing it and the solutions I came up with.
I have always wanted a folding solar panel and when that was one of my choices for 'wowing" them at work, I knew that was what I was gonna pick.
My Primary use was going to be used to charge my iPhone and ham radio HT on backpacking trips into the wild. So needless to say when I got the package in the mail I was excited.
When I finally got around to testing it, I was pleasantly surprised when I plugged in my iPhone and heard that cool sounding 'chirp'. I even got ONE pic of it actually charging.
Then a strange thing happened. I got an error message on the iPhone the next time I plugged it in, saying, "This accessory is not compatible with the iPhone".
I checked the voltage with my handy dandy voltage meter and it read 15V DC. A little HOT but should be able to charge the iPhone.
As a precaution I hooked up my charge controller and dropped the voltage to 13V DC.
I noticed that sometimes the panel would allow the iPhone to charge and other times it wouldn't (as a cloud was passing in front of the sun).
It then dawned on me that although the meter was reading the same VOLTAGE, it was not providing the same AMPERAGE!
Thus the iPhone was wondering, "What kind of crappy power is this???" and refused to continue to allow its use.
I needed someway to stabilize the voltage, and who really want to leave their iPhone in camp as the go hiking away in the wild???
The easiest way was to construct a simple battery pack. So after a trip to the local Radio Shack (their motto should read, "You got questions??? So do WE!!!"). I finally found enough 'parts' to come up with a working prototype (still need an on/off switch).
As a side note, is it not funny how you can go into a Lowes, Home Depot, Ace Hardware, or Radio Shack and they NEVER have exactly what you need and you have to figure out a little different way to do the same thing with other items???
Well that is what happened at Radio Shack. I wanted to use NiMh D cells but they did not have 12, so I had to go with AA's.
I purchased an 8 cell battery stick/magazine as well as a 4 cell battery stick/magazine for AA's. In series, the 12 AA batteries give me 14.4V DC. Add a 12V lighter socket,plug and project box and you have yourself a nice little power source that will power almost any 12V DC gizmo for a time (think cellphones, DVD players, ham radio walkie talkies, etc.)
After I put it all together I now have a power supply that will store that solar energy that my panel harvests and be able to use it when I need it. I can even use it for other purposes for when I need a small 12V DC power source.
The point of this whole blog entry tonight is that had I assumed that my nifty little solar panel would charge my iPhone in the remote wilderness and found out that it performed as I just told you, I could have been in a world of hurt.
Remember... If you don't test it, you don't know it will work and thus should not count on it until it lives up to your expectations! Test... Test and ReTest.
No one should EVER find themselves with their tail on the line with a piece of unproven gear that has failed!!!
*EDITED TO ADD ON 7-21-2009* Al asked me a technical question about including a blocking diode (to prevent the battery from being drained at night if left hooked to the solar panel) which I probably should have mentioned that the solar panel has a 'built in blocking diode' that prevents this. Great question and no, I did not include one as the panel takes care of this for me. Still it will not hurt to add one in the future. SO MAKE SURE that your panel has a built in blocking diode to prevent that energy from leaving your battery if you leave it plugged in overnight!!!
Thanks for reading!
Later,
ZA
