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Old 05-16-16, 11:03 PM   #7
Bicycle Bob
Join Date: Sep 2008
Location: Spiritwood, Northern Saskatchewan
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Default Parts Hacking

On Steve Roberts' Microship, he wanted very light but rigid panels, so he got a donation of plastic-coated silicon cells just lacking the usual aluminum backing. They would easily bend around a 1m diameter, and would probably have been OK down to 30 cm or less, but they were fragile until glued down. The efficiency was the same as the rigid panel, except for exposure angles if curved.
So, it may be possible to etch away an aluminum backing until it is thin enough to bend without cracking the silicon, or get rid of it completely if the next layer is resistant. You can dissolve any amount of aluminum in Sodium Hydroxide, commonly sold as Fantastic brand cleaner. Unlike acid, it is not diluted by the metal; it turns it into aluminum oxide and liberates hydrogen, so you only need to replenish the water and clean away the gunk. (BTW, you can fill a party balloon with hydrogen from a beer can, instead of wasting helium.)
Steve's panels were a failure because the sandwich panels we mounted them on let them heat up too much in the sun. That aluminum backing is for cooling, and must be exposed to air or equivalent. With improved cooling, you can probably double your output with mirrors fairly easily.

Last edited by Bicycle Bob; 05-16-16 at 11:17 PM.. Reason: Unsafe practice deleted.
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