The graph below compares the total amounts of greenhouse gas emissions expected for future mid-size cars, including emissions that occur when moving fuels from their original source to fueling stations where people can buy the fuels for their cars. Amounts are shown in grams of CO (or equivalent greenhouse gas) per mile driven by the mid-size car. Which vehicles are the best choices for environmentally friendly cars?

fuel cell electric and battery electric
hybrid electric and plug-in hybrid electric
conventional internal combustion and hybrid electric
conventional internal combustion and battery electric