You're probably right about coal power plants. The point of the meme is that liberals think that, since electric cars produce zero emissions, they are "saving the planet". But they totally ignore the fact that most of the electricity they use to charge their cars is produced by sources they oppose; such as coal, nuclear, hydro electric (they want to get rid of the Hoover Dam and others).
As far as electric cars that run/recharge from soar - we're a long ways away from that being reality.