How Does the EPA Determines MPG Ratings?

June 1st, 2010 by

Have you ever wondered how the Environmental Protection Agency estimates Miles Per Gallon, the estimates you find on the window sticker?

Test are performed in a laboratory on a machine called a dynamometer that simulates the driving environment. A professional driver runs the vehicle through a standardized driving routine.

A hose is connected to the tailpipe to collect the engine exhaust. The carbon in the exhaust is measure to calculate the amount of fuel burned during the test.

See video on how vehicles are tested

Beginning with 2008 models, all fuel economy estimates are based on new test methods, which EPA finalized in December 2006. The new methods better account for actual driving conditions that can lower fuel economy, such as high speed, aggressive driving, use of air conditioning, and cold temperature operation. The new estimates will give drivers a more accurate estimate of the fuel economy they are likely to achieve on the road. Because of the new methods, the estimates for most 2008 models will be lower than their 2007 counterparts. From EPA’s site

Do you have a smart phone? Get MPG information at your fingertips from your mobile device, smart phone or PDA www.fueleconomy.gov/m . This site has EPA ratings from 1984 to 2011.

Some of the most fuel efficient cars on the road today are Honda’s, check out the Honda Civic, Honda Insight, Honda Civic Hybrid and Honda Fit.