My Week Driving the Chevy Volt: Part 2

Last week, I reluctantly handed back the keys to the Chevy Volt that I had the opportunity to test-drive for seven days. As I wrote in my last blog post, it was a smooth, quiet, oil-free, and fun driving experience for my whole family.

This week, I challenged myself to make some calculations about what a switch to a Volt or another plug-in vehicle would mean in terms of my family’s own emissions and oil use. I hope some of you will be inspired to make your own calculations if you haven’t already.

Chevroley Volt, Chevy Volt, Volt, Hybrid, Hybrids

image via Chevrolet

According to a new very helpful Department of Energy Calculator, the emissions we spew into the air from the 2005 gas-powered vehicle that my husband and I share for carting around ourselves and our two daughters is a whopping 11,646 pounds each year (this makes me sick to consider). We purchase about 485 gallons of gas a year. Factoring in fuel, tires, maintenance, registration, license, insurance, (basically all but purchase price), the DOE tells me that our cost per mile is $.35.

If we drove the Volt, our emissions would decrease to 5,672 pounds per year (from a combination of tailpipe and smokestack sources in Massachusetts where we live), our gallons of gas purchased would go down to 159 gallons, and our cost per mile would decrease to $.25.

If we drove a fully electric Nissan Leaf, our emissions would drop to 4,169 pounds per year, our oil use would plummet to zero, and our cost-per-mile would be as low as $.18.  However, we frequently drive to visit family in other parts of New England, so we would need to borrow or rent a longer range vehicle -–thus throwing off my calculations (this would work better for a two-car family or one that makes infrequent trips over 100 miles).

If we drove a Prius, our emissions would be at 5,534 pounds a year, our fuel consumption would be 231 gallons annually, and our cost per mile would be $.27.The plug-in Prius (for which Toyota coincidentally opened up the waiting list in certain states this week) is too new for the DOE calculator to let me determine my emissions. However, based on my own back-of-the-envelope calculations, if we drove the vehicle, we would purchase about 122 gallons of gas a year (the least among the cars not fully electric).

So, for me without taking into account the cost of the vehicles and the availability of charging infrastructure (subjects for other blog posts), the oil, emissions, and cost-per-mile benefits would improve as I go from conventional to extended range electric to plug-in hybrid to fully electric.

But, it’s important to consider that some people live in areas where the grid is cleaner or dirtier than mine here in eastern Massachusetts (we have about 15 percent coal in our mix compared to well over 50 percent or as low as zero in some parts of the country). Also, one interesting thing I found in doing my own calculations was that the majority of my family’s annual driving miles are on the highway for long-distance weekend trips, while the remainder are for short local trips under five miles. Most American drivers have different driving patterns. These factors will change your results.

I then considered what would happen if we installed solar panels on our roof, something we’re planning to do in the next year or so. According to oneNational Renewable Energy Laboratory(NREL) study, relying on grid-connected solar for the electricity to power our home and vehicle would approximately halve our electricity-related emissions.  Mike Simpson, a Vehicle Systems Engineer at NREL’s Center for Transportation Technologies and Systems, further explained to me that more important than anything we would be doing to reduce our own family’s emissions, our solar could be offsetting the peak load demand on the grid, and the combined effect of a lot of people switching to solar may well reduce the need for new power plants.

What if we’re not ready or able to switch to solar? Max Baumhefner recently suggested in an NRDC blog post that people should visit buycleanenergy.orgwhere “for $20, you can buy enough RECs [renewable energy certificates] to cover a year’s worth of driving.”

Here is another interesting thing I learned about my own calculations: I grossly under-estimated the number of miles my husband I drive each year. When I added up what I thought we drove on a weekly basis (not too much given that we often walk, take the bus, or take the train) and then added our frequent trips to visit family in other parts of the northeast, I estimated a total of less than 6,000 miles a year. However, the odometer told me that the annual result was more than 11,000 annual miles (I checked my math many times and even took the car for a drive to check the odometer accuracy).

This made me wonder if other people are also under-estimating their miles driven, as well as their emissions, oil use, and spending on gasoline.  In fact,Consumer Reports says that it came up with a national average of 12,000 miles per driver per year from simply asking their survey respondents. If we’re all underestimating the impact of our driving on our health, our environment, and our pocketbooks, then we’re in even worse trouble than we thought.

We already knew that a hybrid, plug-in hybrid, pure electric, or extended range electric vehicle is always going to be cleaner than a traditional vehicle, even on today’s electricity sources (see our Sierra Club fact sheet). What many people may not realize is that determining our emissions and oil use is the result of a complicated equation that will greatly vary by person. It will depend not only on our choice of vehicle, but also on our electricity sources, the (real) number of miles we drive a year, how many long-distance  miles we drive (beyond the range of many of today’s EVs), and the percentage of those miles that are highway vs. city. Lucky for us, this new DOE calculator makes this easier to figure out.

As I work out what to do with my EV-withdrawl, I’ll end this post with words by Chuck Frank, a Sierra Club supporter and former owner of Z. Frank Chevrolet in Illinois who recently took delivery of his new Volt:

“I am proud to be an early adopter for a new technology in transportation.  I am delighted…that we don’t have to have our foreign policy controlled by favoring oil rich countries….And I feel good about reducing the amount of CO2 I burn that is destroying our…climate.  I hope that as more electric vehicles come on the market at a price more people can afford, that more…people will join me in shaping the world that we will leave for generations to come.”

Editor’s Note: This news feature comes to us as a cross post courtesy of Sierra Club. Author credit for the feature goes to Gina Coplon-Newfield.

The Sierra Club is America's largest and most influential grassroots environmental organization. We are working to protect our communities and the planet.


  • Reply November 23, 2011


    Comparing Auto Insurance With your enables you to find out whether you are paying too much or less than others in neighborhood.Insurance companies basically provides insurance rate depending on where you are now living.You are not required to provide your personally sensative information to receive the result.It takes only a few minutes.u00a0http://www.insurancebread.comWe believe Sharing is always Good!

  • Reply November 25, 2011


    First, let me say that I commend anyone who is willing to be an early adopter of new technology.nNow, about the article. u00a0Many articles I have read have suggested that there maybe some overloading of the electric grid if too many people switch to an electric vehicle. u00a0I have found this idea mathematically unlikely, and here’s why. u00a0If you do the research I have done, you will find that it takes approximately 8kwh of electricity to create a gallon of gasoline. u00a0This 8kwh of electricity by itself, can propel the average EV the same or greater distance as the gallon of gas it creates will propel the typical gasoline vehicle. u00a0So, the fact is, for every gallon of gas an EV owner doesn’t use, this is one less gallon of gas an oil company has to produce, and 8kwh of electrical energy the oil company will not need to consume.Estimating your mileage. u00a0How can someone under estimate the number of miles they drive each year? u00a0You have an odometer in your car don’t you? u00a0All you have to do is take some notes or divide the current mileage by the number of years you’ve had the car. u00a0How hard can that be? u00a0Don’t they still teach math in the public school system? u00a0Duh!Extended Range Electric Vehicle. u00a0So that is what the Volt is? u00a0Wrong. u00a0I’ll tell you what the Volt is. u00a0It’s a plugin hybrid vehicle. u00a0Its not a purely electric vehicle with it’s range extended by a gas powered generator. u00a0The Volt’s gas engine CAN mechanically connect directly to the front wheels and move the car, just like a Prius, Honda Insight, etc. u00a0It’s a plugin hybrid with a really big battery. u00a0GM wants the public to think that it is only the electric motor that drives the wheels. u00a0Its NOT true. u00a0However, it doesn’t do that for good reason,… its not very efficient. u00a0To have a gas engine turn a generator to generate electricity, and charge a battery, then have that battery be discharged by an electric motor to turn the wheels is very inefficient because there are energy losses incurred at every step. u00a0If you drive a Volt into its range extending mode, it is far more efficient to just let the gas engine drive the wheels directly. u00a0That’s why they did that. u00a0The only problem I have with doing that is that it makes the drivetrain a whole lot more complex. u00a0Too many clutches to wear out in this car. u00a0Its a very heavy and complex vehicle. u00a0That’s my only problem with this car, well that and it’s hideous center console.CO2 destroying our climate? u00a0Really? u00a0Did you know that when one volcano blows it top for a few days, this event will pump more CO2 into the atmosphere than man can in 20 years? u00a0The amount of CO2 man has put into the atmosphere since the beginning of the industrial revolution is but a fraction of the CO2 produced naturally by volcanic activity. u00a0Worrying about the environmental effects of your car’s CO2 emissions is like worrying about the environmental effects of you exhaling. u00a0That being said, I like clean air and reducing particulate matter in the air is a good thing, so is not having to send our money to terrorist countries, but I don’t like electric vehicles because of anything having to do with climate change. u00a0Simple math will show you that that concern is just a waste of time.

    • Reply November 25, 2011

      Pete Danko

      I don’t know where you got your data on volcanoes and CO2nemissions, but it is severely at odds with the current science. From the UnitednStates Geological Survey:nn”Do the Earthu2019s volcanoes emit more CO2u00a0than humannactivities? Research findings indicate that the answer to this frequently askednquestion is a clear and unequivocal, ‘No.’ Human activities, responsiblenfor a projected 35 billion metric tons (gigatons) of CO2u00a0emissions in 2010n(Friedlingstein et al., 2010), release an amount of CO2u00a0that dwarfs thenannual CO2u00a0emissions of all the worldu2019s degassing subaerial and submarinenvolcanoes (Gerlach, 2011).nn”The published estimates of the global CO2u00a0emissionnrate for all degassing subaerial (on land) and submarine volcanoes lie in anrange from 0.13 gigaton to 0.44 gigaton per year (Gerlach, 1991; Varekamp etnal., 1992; Allard, 1992; Sano and Williams, 1996; Marty and Tolstikhin, 1998).nThe preferred global estimates of the authors of these studies range from aboutn0.15 to 0.26 gigaton per year. The 35-gigaton projected anthropogenicnCO2u00a0emission for 2010 is about 80 to 270 times larger than the respectivenmaximum and minimum annual global volcanic CO2u00a0emission estimates. It isn135 times larger than the highest preferred global volcanic CO2u00a0estimatenof 0.26 gigaton per year (Marty and Tolstikhin, 1998).”nn

      • Reply November 27, 2011


        My apologies.u00a0 I stand corrected.

  • Reply February 6, 2012


    global warming is a farce. There hasn’t been any warming since 1997.

  • Reply February 19, 2012


    Nice idea in theory, but if it was truly a good idea I wouldn’t be underwriting your feel good purchase with my tax dollars, the EV idea would pay for itself.  Sometimes I see the EV idea compared to Apple in how a transformation can occur.  The big difference is Apple did it without a government subsidy.

  • Reply February 23, 2012


    Hello to all! I work for a
    casting company. We normally do commercials. From time to time we get hired by
    companies to do market research and this is one of those times.


    We are trying to
    put together a panel of Hybrid electric vehicle owners. We are concentrating on
    certain models for certain panels. The first panel we are trying to create are
    owners of Chevy Volt’s.


    We will be
    putting people on tape on Tues Feb 28 and Wed Feb 29. We will then present
    those people to the firm that hired us. If you are chosen from that round, you
    will get a call from the firm and be part of their chosen panel. I believe it
    pays $100 an hour. You will be asked to participate from anywhere from 1 hour
    to 5 hours but they will clarify once they call you.


    So please let me
    know if you would like to be considered so we can schedule a time on Tues Feb
    28 and Wed Feb 29 to put you on tape. If you are located outside of NYC we will gladly arrange a video chat. 
    We are looking for passionate and eloquent Volt owners who can speak convincingly about the value, pleasure and efficiency of owning a Volt. If you know of other Volt owners who may be interested, please email us at


    Thanks so much
    and please check out our company website.

  • Reply September 23, 2012


    Sorry, you lost me at CO2 destroying our climate…Stick to counting cow farts and let others discuss automobiles…

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