Indeed, it's difficult to exactly price externalities. There are published estimates of the carbon externality. You do you best; it's far better than the "estim

Indeed, it's difficult to exactly price externalities. There are published estimates of the carbon externality. You do you best; it's far better than the "estimate" we currently use ($0). When comparing, you add in the externalities to everything. To be specific: - you don't count the deaths in PV installation as its not an externality. The installers are an involved party; they can (for example) ask for higher wages due to risk. (Also, if you wanted to compare this to nuclear, you need to include deaths building those nuclear plants as well. And possibly mining the uranium.) - you do count the environmental damage during PV manufacturing (and turbine manufacturing, and coal mining, and oil drilling, etc.)