Solar cell metals and their hosts: A tale of oversupply and undersupply

In this paper we develop a “green energy” scenario to investigate these metal-related issues in detail. Among the results of interest are the following: (1) More Se and Te may require mining more copper than can be used, while extracting more arsenic than can conveniently be sequestered; (2) more In and Ge may require mining more zinc than can be used, while extracting more cadmium than can conveniently be sequestered; (3) oversupply mining of copper and zinc will decrease their virgin metal prices, and thereby discourage end of life recycling of those metals; (4) the greenhouse gases produced by mining oversupplies of the host metals zinc and copper will, in some case, exceed the greenhouse gases savings produced by a fossil fuel to solar cell transition; (5) these challenges can be minimized, but probably not avoided, by increasing the recovery rates of Se, Te, In, and Ge from the host metal ores, and by more efficient end of life recycling.