Can you drive a stake into the persistent myth that hybrid cars are bad from a cradle-to-grave carbon footprint perspective? I am tired of someone (who is mechanically inclined and has much more time on his hands than me) going on about the MPG of his 1993 Mustang.
--Russell in Framingham, Massachusetts
I've pounded a stake into the heart of this myth on a half-dozen occasions, sometimes with acerbic wit or by way of a two-fisted feminist theory (scroll down to Feb. 21, 2008). I've corrected its contrarian faithful such as George Will and his disciples, and I've addressed the topic in my book and other venues. But it's time to swing away again, because the myth persists to slither free from its stake.
Roughly 25 percent of the hybrid car's lifetime cradle-to-grave energy use goes into manufacturing it. According to the EPA, the 2010 Prius gets 51 miles per gallon in the city and 48 on the highway, while the most efficient 1993 Mustang (a five-speed stick shift) gets 19 in the city and 27 on the highway. Let's say that the driving is evenly split between city and highway. So the Mustang averages 23 mpg, while the Prius gets 49.5.
If your friend continues to have the time to tinker with, adore, and extol his Mustang for another 150,000 miles, he'll burn 6,522 gallons of gas. The Prius will burn 3,030 gallons in the same 150,000 miles. But since about 25 percent of this amount will have been used to make the Prius, it will actually burn the equivalent of 3,788 gallons, or 2,734 fewer gallons than the Mustang. So the 'Stang will emit about 26 tons more carbon than the Prius over those miles, not to mention a lot more air pollutants like ozone, nitrogen oxide, and assorted hydrocarbons.
Of course, your buddy could lower his carbon footprint to a sub-Prius level simply by carpooling, in the event that he ever attains full-time employment.