Solar panel silicon purity is above 99.98%, and often significantly closer to 100%. Here's a study on "how impure silicon can we use for solar panels", and the

Solar panel silicon purity is above 99.98%, and often significantly closer to 100%. Here's a study on "how impure silicon can we use for solar panels", and they only go up to 100 ppm feedstock impurity: https://www.ecn.nl/news/item/how-silicon-purity-affects-the-performance-of-solar-cells/ https://www.ecn.nl/news/item/how-silicon-purity-affects-the-... Edit: should be "above 99.998%".