Q&A for How to Make a Solar Panel (Copper Sheet Method)

Copper turns a bluish-green color (called patina) when in salt water. This is due to saltwater corrosion.

Copper sheets previously used in solar cells can be melted down and stripped of impurities, to form high-grade copper as a product, but this would require lab equipment.

Unfortunately this method is not efficient for powering much of anything, even something small. It is best used to show the chemistry involved in making solar panels, rather than as a viable solar panel.

The copper sheets will corrode with the salt mixture after long-term use. The plates could be reused if they are still solid and not so corroded that they are burned away or contain large holes. You could always dry and sand down the plates, then heat them again.

With a hot plate, stove or torch. Even heating is best achieved with a hot plate that isn't a coil burner, rather a capped coil that evenly distributes heat.

They are typically made of silicon crystal slices called cells. Silicon is a semiconductor material. When a cell is doped with the impurities gallium and arsenic, its ability to capture the sun's energy and convert it into electricity is improved considerably. When the sunlight hits the solar cell, the energy excites electrons that leave behind holes.

Solar panels can be electrically connected together in series to increase the voltage output, or they can be connected together in parallel to increase the output amperage.

For most applications, 18-gauge copper sheeting (approximately 1.02 mm thick) works best. It offers a good balance of conductivity, robustness, and ease of handling, especially for DIY solar thermal collectors or experimental solar cells. While 16-gauge is thicker and stronger but heavier, 20-gauge is thinner and could be too flimsy for outdoor use. Pure copper (99%+) will provide the best performance; note that commercial photovoltaic panels typically use copper in wiring, not sheeting.