Yah, you wouldn't want to eat, drink, or snort sulfur, but it is a byproduct of a number of useful reactions, plus it is a naturally occurring contaminant of petroleum or crude oil. Light crude has little or no measureable sulfur, while heavy or sour crude has more, sometimes much more sulfur. One of the issues facing the petroleum industry is that the supply of light crude is getting smaller and refineries are having to process more and more sour crude. Desulfurizer units remove the sulfur from the crude, but then what do you do with it? It's good to see that someone is using it for a potentially very useful purpose, i.e., boosting the efficiency of photoelectric arrays.

Oh, the reason you remove sulfur from the crude? When gasolene or diesel fuel containing sulfur is combusted, like in a car or truck engine, the sulfur is oxidized to sulfur dioxide and sent out the exhaust. As it cools, it combines with atmospheric moisture to create sulfuric acid, a strong acid which is behind most of the acid rain we hear about, especially in the northeast US. Bad for plants and other living things, like homo sapiens.