Electric cars are completely gas free, and no emissions spew out of their non-existent tail-pipes, but that doesn't mean they run on happiness and baby farts. If you're plugging it in to the grid, that energy is coming from a mix of power sources, including coal, and if you're charging it with privately owned solar panels, you're going to want it to be as efficient as possible, so you don't have to dip in to the grid.

So if you're trying to not only drive electric, but to truly minimize your carbon footprint, you'll want to keep an eye on the miles per gallon equivalent (MPGe) of the electric cars out there. These are The 10 Most Efficient Electric Cars Built So Far.