Causes of Acid Rain
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Notes:
This diagram shows that 2/3 of SO2 (sulfur dioxide) emissions comes from Utilities (presumably all Electric). This is a well structured compact target for regulation. For NOx, on the other hand, the largest individual sector is Transport (mostly automobiles) which are highly dispersed and difficult to regulate. However the second largest sector is again Utilities.
These considerations suggest that, when considering how to get a handle on the overall problem, focusing on Electric Utilities might be a good place to start.
