TL;DR: Choose the most fuel efficient vehicle possible, or better yet, an electric vehicle.
There are many things you can do to reduce your emissions – all of which are detailed in this book UCS wrote on “practical steps for low-carbon living.” But the world has changed since this was published in 2012, and it is now more important than ever to think about how the vehicle you choose impacts your emissions, and ultimately, your wallet.
Transportation recently became the single largest source of emissions in the U.S.
Our cars, trucks, buses, and planes are now responsible for emitting more carbon pollution than all of the U.S. power plants that burn fossil fuels around the clock to keep our phones charged to play Pokémon Go. And, when looking at what segment of the vehicles on the road is responsible for the most emissions; it’s not airplanes or buses. Instead, it’s the light-duty passenger cars and pick-up trucks that we drive every day.
Improved vehicle design has allowed drivers to hold on to their cars longer. The average age of the passenger vehicles on the road in the U.S. has climbed from 8.4 years in 1995 to 11.4 years in 2014, and UCS has found that the average vehicle will be in service for 15 years. Considering that people drive an average of 13,476 miles each year, each new car sold today will likely be in service for well over 100,000 miles and perhaps more than 200,000.
A small difference in MPG makes a big difference in emissions
Choosing a vehicle that uses relatively less fuel compared to other options in its class will make a big difference on your wallet and emissions. For example, let’s say I want a 4-door sedan and am looking at the 2016 Ford Taurus V6 and the 2016 Kia Optima. Though these are two similarly priced vehicles that offer roughly the same features, the Optima gets a combined mpg of 28 and the Taurus gets 21. This difference of only 7 mpg adds up to a big change in fuel costs and emissions over the long run. After 150,000 miles the Optima would save you over $4,000 in gasoline costs* and over 20,000 kilograms of carbon dioxide emissions – the equivalent of avoiding the burning of almost 17,000 pounds of coal.
An even starker comparison arises if you look at the benefits of choosing a gasoline-hybrid vehicle versus a conventional gasoline-only vehicle. For example, after 150,000 miles, compared to the 21 mpg Taurus, the 2016 Toyota Prius will save you over $6,600* and cut the carbon emissions equivalent to the amount of carbon that is sequestered by 981 tree seedlings that were grown for 10 years.
*In today’s dollars. Note that the monetary savings don’t include a discount rate, meaning that I calculated this based on today’s dollars, not the relative value of a future dollar. If you take the discount rate into account, then the savings are a bit less due to inflation.
Driving on electricity can have the biggest impact
If you are one of the millions of Americans whose driving habits and vehicle needs lend themselves to an electric vehicle (EV) – meaning a vehicle you can plug into any regular outlet to charge its batteries – you can reduce your environmental footprint and cut your fuel spending even further.
UCS analysis has found that the average battery electric vehicle sold today is responsible for less than half the global warming emissions of comparable gasoline-powered vehicles. Even charging an EV in a relatively dirty electricity grid is still clean compared to gasoline vehicles. For example, a 2015 Nissan LEAF driven in Lexington, KY – one of the dirtiest grids in the country due to a heavy reliance on coal power – is responsible for about as much GHG emissions as a gas-powered vehicle that gets 50 mpg. Charging and driving that same LEAF from Brooklyn, New York, however, produces the emissions equivalent of a gas-vehicle that gets 88 mpg. See how EVs fare in your area with this handy online tool UCS developed.
Driving on electricity is also cheap, even compared to today’s relatively low gas prices. The average cost to drive on electricity in the U.S. is the equivalent of paying $1.13 for a gallon of gasoline, and can be even lower when EVs are charged on low cost time of use rates offered by utility companies.
Lastly, let’s not forget that the cleanest car is the one you don’t use, so thinking about how you can bicycle, walk, or take more public transit will help decrease your environmental footprint too. But, even non-car owners can raise the average fuel economy of the cars on the road by helping UCS advocate for policies that are increasing the fuel economy of our light-duty cars and trucks and promoting the adoption of EV technology. Check out ucsusa.org for how you can get involved, and don’t forget to read your fuel economy labels before making your next vehicle purchase.
 Used DOE data for average price of gasoline via: http://energy.gov/maps/egallon, and EPA GHG equivalences calculator for emissions comparisons via: https://www.epa.gov/energy/greenhouse-gas-equivalencies-calculator