Back in September 2008 I suggested how gas mileage should be calculated for range-extended electric vehicles like the upcoming Chevrolet Volt: one set of numbers for electric use, and a second set for after the batteries have discharged. General Motors, of course, saw things differently. It wanted the highest possible numbers, both for CAFE and for advertising purposes. And it appears that GM has gotten its way, as the EPA city rating for the Volt will be 230 MPG.
How is this possible? Through a test that makes almost no use of the gasoline engine. Problem is, this figure doesn’t remotely represent the full cost of operating the vehicle.
In a way, though, such a high number will be less misleading. General Motors has so overshot the mark in lobbying for the highest possible number that even the most clueless person will know it’s BS. If they’d finagled a number in the 80 to 100 range then perhaps the average person might have been misled into thinking it was real. But not now.
I don’t see why it’s so unrealistic. The Volt is designed to function primarily as an electric car that’s not using any gasoline, especially in the city. (GM has said the overall rating will be lower.) Many people will, just like in the test, rarely need to use any gas. The car even has a system that stirs the unused gasoline if the same tank is lasting you months and months.
There’s no great way to measure gas mileage for an electric vehicle, but 230 miles per gallon in certainly far from the extreme.
“230 miles per gallon in certainly far from the extreme.”
How do you know that when they won’t even publish the gas-only MPG? I think it’s a safe assumption to say that the car, using only its gas engine, gets under 40 mpg. That is certainly an extreme difference from 230.
This is like those weight loss supplement commercials where someone says “I lost 50 pounds in two months!” and in tiny print there are a boat load of disclaimers about following a strict diet and exercise and how “results may vary”. Except Chevy doesn’t even seem concerned about disclaimers at this point. I guess they’ll just wait for the first lawsuit.
It may be that running in gas-only mode isn’t very efficient. But the Volt isn’t designed to run in gas-only mode any more than a Prius is. The gas engine is only to recharge a low battery every once and a while, as a fallback for if you don’t plug it up to a wall every 40 miles.