New Vehicles Leave MPG Standard Behind

Washington DC August 26, 2009; The AIADA newsletter reported that according to the Wall Street Journal, high mileage claims for planned plug-in automobiles highlight a deep flaw with the MPG standard: As automobiles increasingly rely on multiple fuel sources, or on electricity alone, gauging their efficiency in terms of gasoline risks giving consumers inaccurate information about the financial and environmental costs of driving.

One problem is that in hybrid vehicles, mileage variation could be extreme, depending on which fuel source is being used. In addition, the Environmental Protection Agency hasn't finalized rules for how it will measure fuel economy on the Volt or other cars that can be plugged into an electrical outlet.

Until then, manufacturers' claims won't be fully comparable. Nissan says its all-electric vehicle, dubbed the Leaf, will get 367 MPG. That number, a combined city/highway figure, is based entirely on converting electricity usage into a petroleum equivalent, because the Leaf won't use gasoline at all.

Although the mileage number is lofty, it doesn't mean that operating the Leaf will be seven times as efficient as driving a 50-mpg Toyota Prius hybrid, because electricity costs vary by region and even by time of day.

Click Here for a chart comparing mileage for several leading alternative fuel vehicles. To read more about changing fuel economy standards, click here.