A while back, I posted a video of a bowling ball smashing into a “Bullet-Proof Coffee Table” that I had built. The idea was that I wanted to test whether or not it really was bullet-proof, only WITHOUT firing guns in my residential neighborhood. I DID have a bowling ball and a ladder, so I decided that a little clever use of gravity might be the right way to go. The impact left an AMAZING looking crack in the glass, and I still get a surprising number of YouTube views of that particular video.
A while back, my friend, Josh, had been doing some work designing a new solar power product – a folding solar panel to recharge USB devices, like smart-phones, tablets, or even GoPro cameras. He asked me if I could lend a hand doing some product photography and testing.
Besides being completely waterproof (which yes, I did test in a river, a frozen lake, and submerged in an aquarium for three days…) he was also going for impact resistance.
So how do you test for impact resistance on a solar panel? Some sort of fancy laboratory test? Nope. Drop a bowling ball on it.
I was also interested in what dropping a bowling ball might do to another solar panel. I happen to own several Harbor Freight solar panels, which I have used for powering my Solar-Powered Power Wheels and charging up my electric riding lawn mower. One of the panels had a defect anyways, so I figured perhaps sacrificing it to the Gods of Gravity might be the best use for it.
I set up my eight-foot step ladder in my driveway and placed the Harbor Freight Panel flat on the pavement directly below it. I climbed the ladder and placed the bowling ball directly above the panel, and then let go. I think the results speak for themselves.
The bowling ball smashed the glass. Surprisingly, very little actual glass came off. There was a relatively small amount of tiny pieces of glass to sweep up, but all of the large pieces of glass DID stay laminated to the panel, even though it was dished to the shape of a bowling ball!
I was curious as to whether or not I could still get any power at all out of the panel, so I tested it out with my multimeter. Open circuit volt testing showed almost twenty volts! Wow, I was sure the panel wouldn’t work at all! Wait a minute…. How many AMPS can it output now? I changed the setting on the multimeter to read current, and short-circuited the panel to itself. The meter read 0.12A. That’s about a tenth of what the panel SHOULD be able to put out. The fact that it could get any current AT ALL to flow is still pretty impressive.
After sweeping up the glass and getting the Harbor Freight panel out of the way, I repeated the test with the Badger Solar Panel, making sure to hold the bowling ball at the same height and center it over the panel. I released the ball and……
The bowling ball basically bounced off the solar panel. It rolled off the driveway and into the grass. I took a look up close at the panel. It was hard to notice right away, but I did see some sort of a mark where the bowling ball hit. It was NOT a crack or dent, but the light definitely did bounce off the panel slightly different in an area about the size of my pinky fingernail. I flipped the panel over and saw that the canvas area right where the bowling ball hit was scuffed up. The impact of the ball drove the entire panel hard enough against the driveway to cut a few strands of the canvas cover.
I plugged my phone in to the Badger panel, and it immediately started charging. The panel was providing its full rated power.
Solar technology is pretty cool stuff! Sometimes it fun to take things apart and see how they work. Other times, trying to destroy things can actually be a useful educational tool as well. (Destructive Testing is actually a really big thing in Consumer Product Testing.) I was shocked that the Harbor Freight panel worked AT ALL after smashing it, and the Badger panel may as well have a force-field around it when it comes to bowling balls. If you want to take a look at that panel, it’s on Kickstarter right now. You can see that HERE.
In the mean time, what’s your experience with solar? Got any stories of your bullet-proof renewable energy system? Let us know!