«Emissions from Photovoltaic Life Cycles» found that even when accounting for the metals required to build PV cells, the efficiency of the cells, and the waste produced, PV cells still emit less global
warming pollution throughout their life cycle than the fossil fuels needed to produce the same amount of power.
That's the finding of a new Harvard study that, for the first time, examines the true cost of coal
throughout its entire life cycle... Clearly, the fact that coal contributes more global
warming pollution than any other source in the nation is far from its only problem.