Is it OK to over-match photovoltaic panels

Though mixing different solar panels is not recommended, it’s not forbidden and things would be ok as long as each panel’s electrical parameters (voltage, wattage, amps) are carefully considered. [pdf]

Is it OK to use sand to clean photovoltaic panels

Probably not, it will probably be dust accumulated on the surface of the panel, perhaps as a result of a storm that has carried sand, sediment, or dust, or it could just be pollution. [pdf]
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