There are no commercial panels made of gallium arsenide. They are used in space, where efficiency rules over everything else, and for certain military applicati

There are no commercial panels made of gallium arsenide. They are used in space, where efficiency rules over everything else, and for certain military applications. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8200097/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8200097/ There was a company, Alta Devices, that planned to commercialize GaAs thin-film (so light on materials usage) solar panels with nearly 30% efficiency, but they were bought up by Hanergy which ran into financial troubles and shut it down. It's not clear what happened to their patent portfolio, but their equipment was liquidated in 2020, and the founder now works for UC Berkeley.