"If early replacements occur as predicted by our statistical model, they can produce 50 times more waste in just four years than IRENA anticipates. That figure

"If early replacements occur as predicted by our statistical model, they can produce 50 times more waste in just four years than IRENA anticipates. That figure translates to around 315,000 metric tonnes of waste, based on an estimate of 90 tonnes per MW weight-to-power ratio." If you conservatively assume that solar panels have the same density as plastic (1g/cm^3), that works out to 315,000,000kg / (1g / cm^3) = 315,000m^3 That's a cube 63m on each side, or approximately one Hindenburg Zepplin. Even if we have to treat those solar panels as toxic waste it doesn't sound like a very difficult disposal problem to me.