I would certainly believe that the smog/pollutants from coal outweigh the benefits, but acording to this [1] Reuters article reviewing this question:
> Even in the worst case scenario where an EV is charged only from a coal-fired grid, it would generate an extra 4.1 million grams of carbon a year while a comparable gasoline car would produce over 4.6 million grams, the Reuters analysis showed.
> Even in the worst case scenario where an EV is charged only from a coal-fired grid, it would generate an extra 4.1 million grams of carbon a year while a comparable gasoline car would produce over 4.6 million grams, the Reuters analysis showed.