The last post included ideas on reducing emissions in freight transport. This and the next few posts will be about reducing the carbon footprint of personal vehicle travel. How much CO2 do cars actually emit? Here’s one formula, provided by

Emissions = (number of miles driven per week * weeks in a year) / average vehicle fuel efficiency * pounds of CO2 emitted per gallon, which is about 20 pounds.

How might this translate to actual emissions in one’s own household? For an idea, let’s assume our vehicle gets an average of 35 miles a gallon:

15,000 miles/35 = 429 x 20 = 8580 pounds of CO2 a year 20,000 miles/35 = 571 x 20 = 11,420 pounds of CO2 a year

Plug in your own car mileage and annual miles and you get the picture. We’re talking about a lot of CO2. Next up: exploring ways to reduce that footprint, starting with shopping behavior.