Nature's photovoltaics—leaves—recycle as mulch. It's a lovely closed-loop system, the very definition of a circular economy. Solar panels are more of a problem. In Europe, manufacturers are responsible for end-of-life-cycle costs, so there's more motivation to figure out a solution than there is here in the US. Still, within the next few years, old solar panels are going to start entering the waste-stream at scale, so there is a lot of opportunity for companies that develop solutions. via Ensia
