A look at a small solar panel set.
A while back I had found a bunch of little solar cells on Ebay for cheap. I hadn’t really looked at them or tested them in any real way but today I wanted to see if they could power even a small project. As it turns out, I would require a great number of them in order to make even an LED light up (Assuming no capacitor or storage device). Since the sun was going down, I needed a constant source of light so I used my desk lamp. Here are the comparisons.
Those are the units I bought. I think I got like 30 for $10 or something. relatively cheap, but not really. I was expecting some decent performance, which I got, but not nearly as much as I expected.
This is the competitor. It’s the old Archer 6-12V solar cell pack. It’s quite old (25 years), the lens is dirty but it still works quite well.
And here is the test cell/array that I soldered together.
Now, keep in mind that this was all done with a desk lamp. I maintained a certain distance from the bulb and only used the maximum measurement received by moving the panel around. Also given are comparitive measurements for the overall visible area exposed to light.
Old Archer Panel | Cheapy EBay panel | |
---|---|---|
Measured Voltage | 5.245V | .162V |
Measured Amperage | 305 uA | 628 uA |
Calculated Watts | 1.6 mW | .1 mW |
Measured Area | 14.05 Sq.in. | 1.6524 Sq.in. |
Cell Sizes | .788in x .563in | 1.063in x .433in |
mW per Sq.in. | .113mW per sq.in | .06 mW per sq.in |
That all being said,you could still run quite a few little things at that low current rating if you were to link together all of the cells for whatever reason. unfortunately, nothing that I want to do could use them. So the lesson for the day is “Quality over Quantity”
Also, as an aside, here’s my new Agilent U1271A multimeter. Works like a dream!!!
Perhaps tomorrow or someday I’ll give figures for sunlit voltages/amperages.