The Smart Fortwo comes on the scene in 2008 and lands the highest GreenAuto ranking for a non-hybrid gas vehicle. With a combined fuel economy of 36 MPG and high marks for greenhouse gas emissions, the Smart Fortwo is becoming the little engine that could. Some have noted it's relatively small size as a drawback, but at GreenAuto we see a car that can comfortably parallel park anywhere, even in Manhattan.

Fuel Economy (City 33/ Highway 41) Combined 36 MPG

Emissions Scores (Greenhouse 9/ Air Pollution 6)