Except it stifles innovation in other sectors. There may be alternatives that are better but aren't subsidized which makes it harder for them to succeed.
this is intentional. the point is we want wind and solar to succeed because they have lower negative externalities. the competing sectors we want to not succeed are things like oil and coal. its a pretty reasonable assumption to make that even with innovations that increase the pollution efficiency of coal and oil, its still not going to be as good as solar and wind.
of course, you might also be referring to alternative sectors like hydroelectric or nuclear or whatever. in that case, i agree with you. that's why a carbon tax is better than subsidies.
