[Blue Bomber Man]

Actually even with 'dirty' energy, plug in vehicles are way more enviromentally friendly than their ICE cousins. The ICE is only 20% efficient or worse, your coal plant is 98% or better, and considerably cleaner. Additionally battery vehicles can be used to stabilize power fluctuations that are inherent to some renewables like solar and wind. It will also stabilize variations in demand between night and day as most vehicles would be charged at night when demand is lowest, which would improve the efficiency of production.