The EPA, or Environmental Protection Agency, is the government entity that gives fuel efficiency ratings to all commercially available light-duty cars and trucks in the US. The EPA also lists the official range of all EVs so you know how far a car can go on a full charge. The agency uses a set of standardized tests under highly controlled conditions to get both of these figures. More info on the tests and procedures can be found on the EPA’s website

In addition to rating vehicle efficiencies, the EPA certifies the range of all EVs, giving owners a standardized way to compare how far each car can drive when fully charged. However, the EPA value often differs from the real world range that a car can achieve. First, all car manufacturers calculate their own ranges and submit their results to the EPA. Only certain car ranges are verified each year. Differences in testing protocols can cause discrepancies. Secondly, the EPA tests follow very strict rules and scenarios - a certain amount of highway driving, certain speeds, and under certain external conditions. In the real world, drivers don’t use their cars in exactly the same way they are tested. Some vehicles get more range in the real world than they do in the EPA tests, and some get less. That’s why Recurrent doesn’t rely on EPA range, but only uses it as a standard measurement to compare cars. 

For EVs, the EPA uses a value called “miles per gallon equivalent,” or MPGe, to measure for efficiency. This value just converts the amount of energy in a gallon of gasoline to a standard, so that different fuel types can be compared. The fuel efficiency values are listed on a sticker, called the Monroney label, that is affixed to all new cars. We go more in depth on Monroney labels in our MPGe article.

The EPA began giving fuel ratings in 1970’s with the passing of the ​​Energy and Conservation Act. It started listing MPGe ratings for PHEVs and EVs (and other alternate fuels) in 2010 for the Nissan LEAF and the Chevrolet Volt PHEV.