Sunlight beats down on a graveyard for dead solar panels in Yuma, Arizona, hundreds stacked in neat piles, waiting for their next life. The great majority of worn and damaged panels are still dumped in landfills. But with more and more piling up, many people know that needs to change. In this desert city where Arizona, California, Sonora and Baja California meet, North America’s first utility-scale solar panel recycling plant has opened to address what founders of We Recycle Solar call a “tsunami” of solar waste. Plans to address climate change rely on massively scaling up clean, solar electricity. The...