That’s an unnecessary task because the externality is near 0. Modern landfills are cheap, plentiful, and relatively benign to the environment. CO2 emissions are

That’s an unnecessary task because the externality is near 0. Modern landfills are cheap, plentiful, and relatively benign to the environment. CO2 emissions are a real problem, landfills are largely an imaginary one. If solar panels are dumpstered at the end of their life cycle but save CO2 emissions, it’s a non-factor. And in any case, they’re made largely of aluminum which is profitable to recycle (which means it will actually happen if its own accord) and a solved problem. Any real negative externalities come in manufacture or installation.