As my colleague Jon Lesage notes in his newsletter, the U.S. Environmental Protection Agency (EPA) may be changing the way it does its MPG (miles per gallon) calculations. Recent news has shown large gaps between claims and truth in the ratings for conventional cars and hybrids, and the car-buying public is rightfully demanding a change. But the way this works for electric vehicles is an even better candidate for revamping.
Since the 1970s, the EPA has provided ratings for all cars sold in the U.S. in terms of estimated miles per gallon, but concern for the use of gasoline had been part of our culture for quite some time. In fact, it was mentioned in “Catcher in the Rye” (1951), but it came rushing to the fore of our consciousness during the first oil embargo in 1973.
Fast-forward 40 years to the day in which electric vehicles are gaining ground, and note that the EPA puts MPGe (miles per gallon equivalent) ratings on EVs – even though they don’t use gasoline at all. This rating means: how far the car goes on 33.7 kilowatt-hours (the amount of chemical in one gallon of gasoline).
Maybe I’m missing something, but this strikes me as wholly irrelevant. EV owners may want to know how much fossil fuel they’re displacing, but that’s not going to come from this figure; the displacement of oil, coal, and natural gas is largely a function of the way in which the power was generated to serve the incremental load represented by that car – and that, in turn, is a function of many things that change night after night, year after year.
This whole MPGe concept is even more meaningless in the case of plug-in hybrids, where some drivers can run their cars on 99% electricity, and others on 99% gasoline. In that case, it’s not only meaningless, it’s overtly misleading.
The answer? Scrap MPG ratings for electric vehicles.