<ads> wrote in message
Solar isn't as popular or practical here in New England and the
dealers I called didn't want DIY competition or potential liability
At a ham radio flea market I bought several backpack loads of small
used panels which the seller said had been salvaged from parking meter
kiosks. The day was sunny enough to test them for open circuit voltage
and short circuit current.to weed out the worst ones, but the best
still varied enough to make combining then into a balanced
series+parallel array tricky. A DC Wattmeter and large rotary rheostat
like this is can find each panel's maximum power point.
Tubular variable resistors quickly become too hot to adjust. My
rheostat is an old Ohmite from the same flea market, but they are
scarce, and I don't know how good the imports are, or if they handle
brief overloads as well as the Ohmite.
Overall the salvaged panels and new connectors cost me $ per Watt,
the same as the HD Grape panels. I hung them from a handrail so the
odd size didn't increase the installed cost.