• Apr 22nd 2010 at 12:00AM
  • 204
The 2011 Chevy Volt's MPG rating could suffer a serious... The 2011 Chevy Volt's MPG rating could suffer a serious blow (GM).

The U.S. Environmental Protection Agency will soon draft a new regulation for the way it calculates fuel efficiency for electric cars, potentially deflating the stratospheric fuel economy numbers trumpeted by automakers in recent months.

In August 2009, GM announced that its new 2011 Chevy Volt hybrid would achieve a stratospheric 230 "miles per gallon," using a calculation that took into account how the vehicle would fare given its sometimes-battery, sometimes-gasoline engine power source. Nissan responded with its own number for its new Leaf electric car, 367 MPG, setting off something of an arms race for efficiency. Without actual guidelines from the EPA, however, the public will be left wondering where these numbers come from -- and whether they're believable. The EPA is unlikely to weigh in until after GM and Nissan launch their new vehicles, which has left the automakers to craft their own efficiency ratings.

"They're not going to have actual rules until model year 2012, which is a little late for the Volt," said Pete Savagian, GM's engineering director for hybrid powertrains. As far as how GM will tell consumers what sort of fuel economy they'll see on the Volt? "We're on our recognizance. I don't exactly know. We'll have to be real careful."

This ambiguity isn't the best for consumers. GM's calculation takes into account only the gasoline used, while Nissan's number was merely an equivalent since its Leaf only runs on electricity. Compounding the problem is that consumers aren't used to fuel economy figures for anything other than miles per gallon.

GM came up with the Volt's number using a guideline from the Society of Automotive Engineers, one that ran the car through a city driving simulation. GM did the same simple calculation for fuel economy that we use for traditional vehicle, dividing the total distance travelled by the amount of gasoline burned. But for a good portion of the test, the Volt was operating on battery power alone, having started the test with a full battery. This effectively adds the 40 miles of battery range to the distance travelled, hence the big mileage number.

"230 [MPG] is not a equivalent," said GM's Savagian. "It's just the gasoline. It does not include the electricity consumed. It only included the amount of gasoline used and the number of miles driven."

The fact that the Volt engine burns gasoline will come into play when the California Air Resources Board (CARB) determines its rating, as well. The Volt will likely not be labeled as a zero-emission vehicle (ZEV), but rather as a partial zero-emission vehicle (AT-PZEV) for using gasoline after the battery power is depleted.

For now, the company's focus on "230" has faded. GM pulled the plug on many of its media efforts that featured the infamous number. In August, the company had launched a television campaign that dovetailed with social media efforts on YouTube, Facebook, Flickr and a blog. All of those accounts have since been discontinued. The domain name "whatis230.com" is still registered to GM, but now redirects to a page about the Volt on Chevrolet.com.

No Current EPA Standard

Confusion over the issue isn't so much political as it is chemical. Gallons and kilowatts aren't easily compared. But political forces are also at play. Right now Nissan, GM and a host of other manufacturers continue to provide their recommendations to the EPA on how the new ratings should be calculated.

Nissan is pulling for a new standard that looks at electricity use not in terms of a miles-per-gallon equivalent (although the company admits it did do this with its 367 MPG claim), but something that takes into account grams of C02 or kilowatts.

"We believe it's probably going to be a new definition," said Tracy Woodard, Nissan's director of government affairs. "I don't know whether you're going to get into grams per mile or kilowatt hours per mile, but I think you're going to see a shift away from miles per gallon."

Last weekend, the Wall Street Journal reported that the EPA was "rethinking" the way they thought about fuel economy, but the agency disputed that claim.

"I think that threw some people off," said an EPA spokesperson in an interview with AOL Autos. "We're not 'rethinking' because we're still thinking. In August, we simply said we're developing it. We haven't yet published the new rule."

"We are waiting for the EPA to tell us how we're going to formulate that," said Nissan's Woodard. "We're all just kind of waiting."



I'm reporting this comment as:

Reported comments and users are reviewed by Autoblog staff 24 hours a day, seven days a week to determine whether they violate Community Guideline. Accounts are penalized for Community Guidelines violations and serious or repeated violations can lead to account termination.


    • 1 Second Ago
  • 204 Comments
      Harvey Mushman
      • 8 Months Ago
      The Volt is not an awful start for a prodution GM, but I'll stick with my first generation Honda Insight. 49.5 MPG liftime average with a CVT transmission and living in the hills. Also the cleanest burning gasoline car made. I'll add ********* had 0 problems in 50K miles. Not too bad.
      cee64e
      • 8 Months Ago
      Gimmea6, the main ecological advantage to electric cars is that yes, while we will be generating more electricity, power generation plants "run" several times cleaner than cars do. You basically move all the pollution to one spot that has huge and complex machinery to handle it. Stuff that is WAY better than just a catalytic converter, and that doesn't factor in that our power generation is slooowly switching over to greener sources such as wind and solar. The infrastructure question is really the one to answer. For most of us, charging a car at home is no issue, your garage probably has a 110 volt outlet and maybe even a 220 volt line (say for an electric clothes drier) already. The real tough part is all those people who live in dense urban areas with on-street parking, like NYC. So your talking a really long extension cord running out the window or wiring every single parking spot in the country for electricity. What we REALLY need is a car built like the most efficient hybrid vehicle on the planet - diesel/electric locomotives. That's right, train "engines". There you have a small (compared to the whole train) diesel engine driving a generator that feeds the electric motors on the wheels. Of course, the performance isn't what you'd call "stellar".
      kwikfix91
      • 8 Months Ago
      YOU BASHERS SHOULD GIVE AMERICA A CHANCE. GM IS TRYING TO DO THE RIGHT THING HERE. I THINK THE VOLT IS A BOOST, WE DO HAVE THE TECHNOLOGY. IF YOU DONT LIKE IT SUPPORT OTHER COUNTRIES AND BUY THERE CRAP. BUY AMERICAN
      • 8 Months Ago
      why do they insist in rating these cars (hybrid, elec. etc.) in miles per gallon? If I carried a 5 gal. gas can for a mile, what kind of mileage would that be???? They rate these cars in MPG, but of course, if the elec. part is used, the gas is not being used. .... wonder how come I get such good mileage???? How much mileage does JUST THE ENGINE get? Don't confuse people with these stupid claims of astronomical mileage, we are not stupid!
      • 8 Months Ago
      One of my friends on facebook recommend me a nice dating cite SEEKxxxRICHxxxBEAUTY. CxxxOxxxM , he said that millions of blacks and whites, rich men seeking beauties and women seeking wealth men at there. I am not rich, but i take a try and find many friends there now. I feel a little lucky and happy. You deserve seeking your own wealthy lifestyle.
      • 8 Months Ago
      Yeah how about letting GM prove it before you started bashing them. It is people like you who have helped bring a giant to its knees. GM as a company has had its fiascos granted, but which automaker has not, Hello Toyota! But when GM is on the ropes suddenly a bunch of nobodies you know next to nothing about cars or even less than that all of a sudden are experts on the matter. I don't give a damn if the Volt get 10 miles to the gallon or 230 miles to the gallon it is inovation which is something that GM has always done and one day GM will be the giant it once was and any asian automakes in this country will return to their country of origin which is where that money goes anyhow. So take some advice, shut up, sit down, and wait and see what the Volt can actually do before the naysayers like you start filling the air with ********. Jerk! Have a nice dlay moron.
      kafienkarl
      • 8 Months Ago
      the auto bailout started on the bush administration watch and was passed on to obama. the notion thay the "union" was what brought down GM is short sighted/ridiculous. GM had too many brands and too many dealerships. their advertising was very expensive. GM went into the "Hummer' market a vehicle that got a boost if you will from the war(s) and bush tax credits, instead of working on/manufacturing fuel efficient vehicles. strictly blaming the "unions" is the linguistic path of least resistance for simpletons.
      • 8 Months Ago
      A friend of mine drives a diesel VW and it gets 48-50 mpg. Obviously, the technology is available. I have a Jeep Liberty that gets about 22mpg on a good day. My solution, when faced with the reality that a new, more efficient car would cost upwards of $40,000 is to ride my bicycle on short trips and my Yamaha Vino (motor scooter...95 mpg) on longer trips. I only use my car when I need to make the infrequent large shopping trip. Granted, I do use my car in inclimate weather, but I have reduced my annual fuel costs in half over the last few years. There are other solutions. I have friends that live in Spain that do not owe a car. They use public transportation whenever possible and the occasional cab when not. For holidays they rent a car. For them it means no cost of vehicle, no automobile insurance, no fuel cost, no registration, no maintenance, no parking fees etc. Fuel conservation is as much about life style as it is technology.
      mark peterson
      • 8 Months Ago
      ford is also UAW and old henry hated jews
      motomike137
      • 8 Months Ago
      What is the point of this article? Besides the author using a controversial headline to get us to read his drivel. The bottom line once you walk away from all the hype is that this is a big step in a new direction coming from a company that is coming back and digging its way out of a public perception hole. this car potentially represents step one in the development of a more efficient way for us all to continue to enjoy are freedom of personal mobility. GM should (and will) be applauded for this car and the out of the box thinking that will allow you to enjoy daily driving on electric power with all the amenities we are used to without the penalty of having to stop for a recharge on a lengthy drive.
      • 8 Months Ago
      If it really uses so little gas, why can't they make this car burn hydrogen for the little fuel it takes to operate it? Can't you have a hydrogen alternator that only turns on to generate enough hydrogen the car needs to keep in storage for operating?
      • 8 Months Ago
      charge your battery from home solar panels and save all around
    • Load More Comments
    Share This Photo X