And for those who hope to do it all without any government help, you might consider the fact that fossil fuels have had subsidies for a very long time, and that the apparently very cheap cost of coal (for instance) would be much higher without said subsidies, and if the cost of cleanup were factored in.
I even read recently that the true cost of solar may actually be less than coal now... (Believe I posted the article here a few months ago.)
Oh, and not all alternatives are equal. Hydro can never supply all our needs, for example, and even wind is problematic. Others are much further off.
Not that we shouldn't use those that work, as we do now... but to fully replace fossil fuels, the sun is the best bet, for many reasons.