Question on DIY solar panels

[Jack5885]

I have been wanting a solar panel to help out my battery since there is very little room to install a second battery in my Xterra. Has anybody used a solar cell kit to build their own panel? The cost is quite a bit lower that prebuilt ones, and I have very limited funds at the moment since I'm still in school.

I could make a 72watt panel for just over $60 with this: http://www.amazon.com/Prime-Solar-Ce...ds=solar+cells

Anybody have experience with these sorts of kits?

[dwh]

Hobbyist PV modules work just the same as commercially made - cells are cells and all put out around .5v.

Commercially made modules have an anti-reflective coating (sometimes on the cells, usually on the tempered glass) to help keep photons from bouncing off, which helps efficiency. You won't get that with a hobbyist module unless the coating is on the cells.

The main issue is water/moisture intrusion and longevity because there is no way for a hobbyist to do a proper vacuum epoxy sandwich. I suppose vibration would also be an issue if you are traveling with it.

Commercially made modules are fairly tough. I would think hobbyist panels would be the opposite.


By the time you add the other costs, such as backing, framing, glass and wire, you probably won't save as much as you would think at first glance. Your "cost per watts harvested" (i.e., watts that actually end up in the battery) will likely end up higher than with a commercially made PV module.

I would expect a 72w hobbyist panel to put out around 40w-50w when it's sitting in good sun and running hot. Depending on how it's built - maybe running very hot. And that's if you use glass. If you use Lexan - probably even less.

[DaveInDenver]

Some of the issues dwh mentions are solvable by a hobbyist, maybe getting glass from an old broken house window that has a low-E coating or something. I'd use tempered for sure, probably low iron if you could find it (not something a hardware store would carry). I'd avoid plexiglass since it's too flexible. Something thick enough not to distort between temperature extremes would block a lot of light I'd bet. Commercial panels usually bond the cells to the glass, so a long lasting seal. But making a laminate of glass/cell/plexiglass sealed around the sides with silicone would probably work fine, too. I'm not 100% sure it's going to be any cheaper but DIY will let you build /and repair/ exactly what you want at least.