Q and A

If your friend is going to the same place with their parent as you are, but instead of taking two cars, you all go in one. Isn’t the additional weight in your car mean your car will get worse gas mileage? And if your car is getting worse miles per gallon, aren’t you polluting more?

Yes, it is true that adding additional weight to your car, such as people, means that your car will get slightly fewer miles per gallon.  This in turn produces more pollution.  However when we do the comparison between your two options (car pool or no car pool), we also need to take into account the weight of the cars.  Let’s do the calculations:

With Car pool:    1 car (4000 pounds)

                             + 4 people (560 pounds)


                            = 4560 pounds 


Without Car Pool: 1 car (4000 pounds) + 2 people (280 pounds)

                                + 1 car (4000 pounds) + 2 people (280 pounds)


                               = 8560 pounds


In fact when you use two cars, both with less people, overall there is more weight and more pollution produced. 


* NYT, Average U.S. Car Is Tipping Scales at 4,000 Pounds