Solar panels have powered an energy revolution over the past decade—up from less than 200 gigawatts (GW) of installed global capacity in 2014 to a whopping 2200 GW in 2024, according to the International Energy Agency (IEA). While this boom has been great for energy independence and emissions reduction, it has also accentuated a looming problem: how to deal with the huge amounts of waste that will build up as panels reach the end of their lives. The IEA estimates that by 2050, there may be as much as 80 million tons of solar panel refuse—an amount that, as Martin Späth at the Netherlands Organization for Applied Scientific Research (TNO) points out, weighs more than 12 pyramids of Giza.