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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Do solar panels require quartz sand

To build solar panels, silica-rich sand must be extracted from natural deposits, such as sand mines or quarries, where the sand is often composed of quartz, a form of crystalline silica. [pdf]
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