I was thinking along the lines of a solar engine, where the cap would be replaced with 4 batteries (4.8V). That way it would charge then discharge. I found a 1381 solar engine that I think I would like to incorporate into the design. Once it got to a preset level, it would turn on and run. A zener diode rated at 5.1 volts or somthing would turn on when it reached a good level. The solar panels could charge each individual Panel with diodes on them to keep them from connecting in series, so each of them charge their own battery, while the batteries are connected in series and would then trip via a zener or 1381. any tips, because this method sounds good to me if we can get it.
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go under circuits, solar engines, type 1, and 1381 or zener based.