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Are Chevy Volts Really Cheaper and Cleaner? A Case Study

The views expressed are those of the author and are not necessarily those of Scientific American.


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A 2011 Chevy Volt owned by someone other than my parents. Credit: flickr/NRMA New Cars

Whenever Scientific American posts an article about electric cars, we see comments along the lines of “electricity comes from burning fossil fuels, so electric cars don’t really reduce your carbon footprint, and the electricity is more expensive than gas anyway,” possibly with more expletives. Ignoring issues of civility, it’s a good question. There’s no such thing as a free lunch: the energy to run a car has to come from somewhere and cost something.

My parents got a Chevy Volt last October. The Volt is a plug-in hybrid. After being charged, it can run for 25 to 50 miles on electricity, depending on temperature, terrain and driving style. Then a small gasoline engine kicks in, either charging the battery or powering the motor directly, depending on what is most efficient for driving conditions. In light of the concerns raised in recent electric car comments sections, I thought it would be interesting to figure out my parents’ costs and emissions for running the Volt. This is just a case study, and I promise that my parents are not a representative sample of the country. But they are real people who are using a Volt for everyday driving, so their experience might help elucidate the environmental and monetary costs of driving a plug-in hybrid.

First, I should say that my parents love their Volt. It feels good to drive, and my dad likes being an early adopter of new technology. He enjoys all the ways that their vehicle keeps track of its energy usage, and as a statistics geek, he likes running the numbers himself to see what his mileage is. They didn’t choose the Volt because they thought it would cost less or reduce their carbon emissions; my dad was in the market for something sporty, and my mom talked him out of a Corvette and into a Volt. For her, one of the big reasons was energy independence. Even if it comes from dirty coal, electricity is not foreign oil.

The Volt takes about 10 hours to charge using a regular 120 volt power outlet, but my parents got a 240 volt charging station in February as part of the EV Project. The EV Project paid most of the cost of installation of the charging station, and they are collecting driving and charging data from thousands of plug-in vehicles in order to make recommendations about charging infrastructure as electric vehicles get more common.

I logged on to the various websites where my parents’ information is recorded to see how much electricity they’ve used and what kind of mileage they’re getting. There were 11 months of the following data: total miles driven, electric miles, gas miles and electricity consumption.

As of Wednesday, when I looked up the information, my parents had traveled 10,102 total miles in their Volt, 9,186 (90.9 percent) by electricity and 916 (9.1 percent) by gas. They had used 2,437 kilowatt-hours of electricity and 24.4 gallons of gas. They can usually get about 43 miles on a full battery; my dad’s office was 19.5 miles away from home, so he could usually get to work and back on one charge.

For individuals, the cost per mile is an important measurement. The car came with a full tank of gas, so my parents have only bought 18.9 gallons of gas for a total of $66.70 (my mom jots down the amount of gas and price whenever she refuels). For the other 5.5 gallons, we’ll use $3.50 per gallon as an estimate for the typical premium gas price for the area in October 2011, giving us another $19.25 of gas costs for a total of $85.95. They have a 12-month fixed rate energy plan. Their rate has changed a little bit in the time that they have had the Volt, but on the more expensive plan, they paid $0.0885 for each additional kWh. Using that price, we get $215.67 spent on electricity. That brings us to a grand total of $301.62 for the 10,102 miles they drove, or three cents per mile. For comparison, with an estimate of $3.50/gallon gas, a 2012 Prius that gets 50 miles per gallon costs seven cents per mile, and my 2004 Saturn station wagon costs 14 cents per mile on a good day.

Of course, many Volt owners buy them for environmental reasons, so knowing the carbon footprint is important, too. My parents, who live in Dallas, have a 100 percent wind power plan, so in some sense their carbon emissions from electric driving have been negligible. But it’s not like there’s a power line from a wind turbine to their house. They’re sucking energy out of a big pool, so it’s reasonable to look at the way electricity is generated in Texas to get an idea of the environmental impact. (Even more difficult to suss out is the “marginal” energy source, or what will produce the extra electricity used by the Volt. Scientific American took a look at this problem back in 2010. That study analyzed what the energy sources would be for a future with a much larger number of electric vehicles on the road. For my purposes, the current sources of Texas electricity seem more applicable.)

According to the U.S. Energy Information Administration, energy in Texas is 45.4 percent natural gas, 36.5 percent coal, 10 percent nuclear and 7 percent renewable, with small contributions from other sources. Using the EPA estimates on carbon emission, this energy mix means that every kilowatt-hour of electricity generates 1.336 pounds of carbon dioxide. For my parents’ electricity usage so far, that’s 3,256 pounds of CO2. The EPA estimates that each gallon of gas releases about 19.59 pounds of carbon dioxide, so the Volt has also emitted 478 pounds of carbon dioxide from gasoline for a total carbon footprint of 3,734 pounds of carbon dioxide. If they had driven the 10,102 miles using only the 37.5 mpg gas engine, the Volt would have released about 5277 pounds of carbon dioxide. A Prius would have generated 3,958 pounds of carbon dioxide over the same number of miles.

Unfortunately, the carbon emissions of the Volt are not limited to the gas and electricity used to drive the vehicle. Producing the vehicle and its monster battery pack take a lot of energy. Several groups are looking at lifecycle emissions for all types of vehicles, but in this post I am just trying to crunch some numbers myself, and lifecycle emissions involve too many unknowns. (If you’re curious, here are two conflicting reports.) Lifecycle emissions might make a fuel-efficient gasoline car a better environmental choice now, but one point that many proponents of electric vehicles make is that it may be easier to implement more efficient technologies at one power plant than in every internal-combustion engine on the road.

With their typical driving, my parents pay less per mile than they would in a traditional hybrid or gas-powered car. They also emit less carbon dioxide. Overall, they are happy with the car, and we had a lot of fun running the numbers together. Thanks, Mom and Dad!

Evelyn Lamb About the Author: Evelyn Lamb is a postdoc at the University of Utah. She writes about mathematics and other cool stuff. Follow on Twitter @evelynjlamb.

The views expressed are those of the author and are not necessarily those of Scientific American.





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  1. 1. evelynjlamb 12:04 pm 09/21/2012

    Here in the comments section I’m interested in a side question: does miles per dollar or cents per mile make more sense to you as a way to compare different types of cars? I went back and forth about it when I was writing this. They both contain exactly the same information, so it’s just a matter of style.
    In support of miles per dollar, we usually measure fuel consumption in miles per gallon, so it feels like an analogous measurement. Also, larger numbers are better, which is true for many, but not all, things we measure.
    In support of cents per mile, we usually pay for things in that way. For potatoes, we wouldn’t see 2 pounds per dollar, but 50 cents a pound.
    If we were used to measuring fuel efficiency in gallons per mile, cents per mile would be the clear choice, and miles per dollar probably wouldn’t even have occurred to me.
    Any thoughts?

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  2. 2. Michael Moyer 12:25 pm 09/21/2012

    This hits on hobby horse of mine: Miles per gallon is a TERRIBLE way to measure fuel efficiency. People want to know how much gas they’re going to have to buy. MPG isn’t a linear function of that—it’s curvelinear, which distorts differences (and perceptions of those differences). Rick Larrick at Duke has been singing this song for years:
    http://www.mpgillusion.com/2009/02/overveiw-of-gpm.html
    Miles per dollar suffers from the same flaw. I disagree that it’s just a matter of style. Presenting information in a miles/dollar format—instead of dollar/mile—distorts differences between costs.

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  3. 3. evelynjlamb 12:50 pm 09/21/2012

    Yes, I agree that mpg is very misleading! It would be better if we used gallons per mile, but that hasn’t caught on yet, like the metric system. Probably because the auto industry likes the way the distortion works.

    I’m curious about which format means more to people on first glance. If they are used to seeing miles per gallon, maybe cents per mile doesn’t click as quickly. Of course, if you present the numbers for two cars the same way, they can still compare them, so maybe I shouldn’t worry so much about people’s feelings. (And hopefully people know that ratios are more important than absolute differences between numbers.)

    Maybe as electric and plug-in hybrid vehicles catch on more, we will switch to the less misleading way of measuring. It would be great if manufacturers listed cents per mile for all vehicles. What I hate is the miles per gallon equivalent. It’s really opaque, and people can’t easily compute it themselves once they drive the car off the lot to see how their actual number compares to the rating.

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  4. 4. milesmeyer 2:01 pm 09/21/2012

    I have had my Volt for a couple months now and really love it. I get about 4.2 miles/kWh @ $0.11/kWh and 38.5 MPG @ $4.00/gallon. So it is cheaper to drive on electricity (usually 42-48 miles per charge in town and 38 miles per charge on highway). The selling point for me was how much nicer it was to drive than the other hybrids I had test driven.

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  5. 5. drafter 3:45 pm 09/21/2012

    Is there a flaw in this. Per your article “the EPA estimates a gal of gas releases 19.59 pounds of carbon dioxide” Yet a gal of gas only weighs 7.29 pounds. Is this the weight of carbon dioxide created when the carbon is mixed with oxygen in the combustion process?

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  6. 6. Michael Moyer 4:00 pm 09/21/2012

    Drafter: That’s exactly right. The hydrocarbons in gasoline mix with oxygen in the air to make CO2. If you assume gasoline is just a bag of Carbon atoms, and combustion is perfect, and every C atom grabs two O atoms—obviously incorrect assumptions, but it gives you an idea—the final mass will be (14 + 2*16)/14 = 3.3 times heavier than the initial mass.

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  7. 7. Mirzero 5:00 pm 09/21/2012

    Would have loved to see some estimated vehicle purchase and maintenance costs (including battery replacement) amortized across the lifespan of the vehicle, and included in the cost-per-mile numbers. I appreciate you were trying to keep it simple, though, and it’s an interesting look!

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  8. 8. Roto2 5:14 pm 09/21/2012

    Interesting comments. EPA estimates are suspect. The EPA supports stating plug-in and pure electric cars equivalent MPG determine from the KW/mile provided from the battery by comparing to the number of such KW’s to the thermal energy released in the free burning of 1 gallon of gas as stated in KW. Of course, this is entirely erroneous for the reasons stated in the article, i.e. a generated KW only represents a small fraction (about 22%) of the pure heat of combustion used in creating the KW when total end to end losses are considered (obtaining and refining fuel, generator/transmission losses, battery losses, etc). An end to end comparison for gasoline used in ICE engines gives the same 22% net energy per mile for best practice 4 cylinder engines. Therefore, electric cars can not obtain higher MPG on a net energy basis than gas cars. This is particularly true as compared to mild hybridized gas cars (since both pure electrics and hybrids recycle kinetic energy of motion). This is also true for carbon release in today’s electric energy mix. But, as I’ve said before, if someone likes the Volt and/or electrics buy them. It’s your choice.

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  9. 9. Roto2 5:16 pm 09/21/2012

    Correction to above, KWH represents energy so KW=KWH in my comments above.

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  10. 10. markgrogers 9:52 pm 09/21/2012

    This statement- from the “Lifecycle Analysis” is totally BOGUS:
    “Additionally, electric car batteries must be replaced after about four years. When the emissions connected with replacement batteries are added in, the total CO2 from producing an electric car increases to 12.6 metric tons, compared with 5.6 metric tons for a conventional car. Because recovering and recycling the metals in the battery consumes a great deal of energy, disposal produces double the emissions.”

    There are already Chevy Volts that have been on the road more than 2 years and show no signs of battery depletion that would warrant “replacement” in two more years. GM warranties the batteries for TEN YEARS.

    Who came up with this 4 years crap? Fox News?

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  11. 11. zsingerb 10:56 pm 09/21/2012

    I drive 16 miles to work, 16 miles back (32 so far) and another 6 miles to the grocery store. I guess I have to walk home huh? Not practical.

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  12. 12. evelynjlamb 11:37 pm 09/21/2012

    Mirzero, that would be really useful because the production emissions and the up-front cost are a big deal. Unfortunately, I think the lifetime estimates are really uncertain right now and very prone to misrepresentation and faulty assumptions. I’ve only included the operating costs/emissions because I could get my hands on the actual numbers for one case.
    zsingerb, the gas engine kicks in after the battery reaches a certain level of depletion, so you’d never get stranded. (Unless you run out of both battery and gas, of course.) That’s in contrast to the Nissan Leaf, which is fully electric. It has a longer range than the Volt’s battery, but when the Leaf’s battery is depleted, you’d better be at a charging station or ready to walk. If charging stations get more common, this could be less and less of a problem.

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  13. 13. alan6302 1:00 pm 09/22/2012

    The internal combustion engine emits nano-particles. The government does not regulate this component despite the fact it is the most dangerous. New engines are worse.

    Death to the I.C.E.

    My electric bike (scooter) took 1.5 kwh for 25 miles . Unfortunately ,I drove the chinese bike in the rain and it fell apart.

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  14. 14. kupuguy 3:52 pm 09/22/2012

    zsingerb is wrong on so many levels.

    32 miles to and from work plus 6 miles to and from the shops is probably within the normal Volt range if you drive carefully.

    Even if you don’t manage the 44 miles on a single charge all it will take is a short charge at work or at home or at the shops before you set out to the shops and you’ll easily cover that distance on battery power.

    Even if you cannot charge at work and go straight out to the shops without any kind of charge and do run out of battery the Volt will seamlessly switch over to the internal combustion engine.

    As good example of this pattern of use, this morning I drove to the shops and home again, 4 miles each way. I then plugged my Volt in to charge (and it was sunny so my solar panels provided most of the power needed). This afternoon, fully charged again, I went out again to some different shops 26 miles away. That left me with about 18 miles range, not enough to get home, but no problems, I just plugged in to the public charge point. By the time I left to come home I had 26 miles of range again, plus I came home by a shorter 23 mile route and had 3 miles of range left by the time I got home.

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  15. 15. outsidethebox 4:24 pm 09/22/2012

    Why is not the differential between the cost of a Volt and a similar gasoline powered vehicle being considered in the cost per mile analysis? Given the current price and technology, for 99% this is an “investment” that will never break even. As a political statement it might be worth it to you but economically, no.

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  16. 16. evelynjlamb 5:38 pm 09/22/2012

    You’re probably right, outsidethebox. For my parents, it wasn’t a political statement. My dad was looking at more expensive cars already, so cost-wise it was probably in line with the others he was considering. He really liked the way the Volt felt to drive, and he also liked geeking out on the mileage analysis and being an early adopter.

    The reason I didn’t include a purchase price differential is that there’s so much speculation that goes on for the total cost analysis, especially for a car that hasn’t been out for very long. But I can include some back-of-the envelope calculations here in the comments.

    A lot depends on how long you keep the car, when the battery has to be replaced, and how much that will cost. I’ve seen estimates from 4-10 years for battery life, which means that no one really knows. It’s also likely that maintenance will be higher because it’s not the typical automobile technology. I’m going to ignore those and just look at breaking even on fuel. Dallas gas is pretty cheap. At $3.50 a gallon, the Volt is 3 cents per mile, a Prius (50 mpg) is 7 cents per mile, and a Civic (estimated mpg 32) is 11 cents per mile. Estimated purchase prices: Volt 32,000 after tax credit, Prius 24,000, Civic 16,000. (I just got those numbers from the manufacturer’s websites, so I’m not sure how it would work out if you were actually buying one and wanted additional features.)

    To make up the 8,000 cost difference between Volt and Prius, you’d have to drive 200,000 miles, and to make up the cost difference between Volt and Civic, you’d also have to drive 200,000 miles. (Funny.) But that’s assuming low gas prices. If gas rises to $5 a gallon (it’s only a little less than that where I live right now), the Volt’s cost per mile will only go up a little (let’s say to 4 cents), while the Prius is now 10 cents per mile, and the Civic is 15.6 cents per mile. At those prices, you need to drive 133,333 to win against the Prius and 137,931 for the Civic. If gas prices increase even more, the break even point decreases. 135,000 is a lot of miles, so it’s safe to say that the Prius and Civic are better buys now. I hope that in a few years, electric vehicles will have come down in price, and we’ll have a better idea of how long the battery will last and how much it will cost to replace.

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  17. 17. GreyHare 7:58 pm 09/22/2012

    10,102 miles in eleven months comes out to about 11,020 miles annually. That would be close to average if your dad is over 65 and the primary driver, but if he is still commuting to work every day I would expect his average to be closer to 15-16k miles in a year (comparing numbers from the Federal Highway Administration here: http://www.fhwa.dot.gov/ohim/onh00/bar8.htm).

    It would be interesting to compare the usage of the Volt to the usage of the car that your dad drove before the Volt- in other words, has your parents driving pattern remained constant, or have they shifted some usage to a secondary car or other form of transportation because of the charging cycle of the Volt? The range/charging cycle issues are a major barrier for a lot of drivers to using a pure plug-in option, or taking advantage of the plug for hybrid plug-ins. If a family puts more miles on a second, non-hybrid car as a result of the charging cycle, that has implications both for the larger-scale adoption of plug-ins, and for the ecological savings- if some of these ‘shifted’ miles are coming from less fuel efficient secondary vehicles that were previously driven only incidentally (like a van, SUV, or truck), then it would really cut into the carbon savings from the plug-in model.

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  18. 18. oldvic 3:56 am 09/24/2012

    I have an electric bicycle that carries me to work every day, using the motor in the morning to avoid sweating. The lithium-ion battery is 4 years old, with around 170 charge-discharge cycles on it.
    It has a thermal protection system that shuts the motor down when it reaches a low charge level to prevent damaging the battery, and so far there’s no discernible loss of capacity.
    In my experience, if the battery is put together properly and used as it should, the “lifetime” problem is non-existent. And with warranties from the manufacturers, the customer risks very little.

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  19. 19. Slugsie 10:24 am 09/24/2012

    One quick observation. Typically when calculating CO2 emissions for a gas powered car only the amount of CO2 emitted by the car burning the gasoline is provided. If you want to do a true apples to apples comparison you need to also factor in the CO2 emitted in the production and refining of the gasoline in the first place. Hint, gasoline refining uses a LOT of electricity, which obviously generates CO2 in the same way the electricity used to charge an EV does.

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  20. 20. evelynjlamb 11:59 am 09/24/2012

    GreyHare, interesting observation. There are a variety of reasons that the mileage is kind of low for the year, including a big hailstorm in Dallas that caused some damage and kept the Volt in the shop for a while. Those factors didn’t really seem pertinent to the discussion :) . In general, the shift of miles could be a concern. I have no idea if that has occurred with my parents. Even when using the gas engine, the car gets very good mileage, and you wouldn’t actually get stranded unless you forget to fill up the gas, so I would assume that people wouldn’t shift their usage to a car with lower mpg even when going out of electric range. But there are times when you might need a larger car to transport more passengers or furniture/kayaks/bicycles/other.

    oldvic, The Volt battery also stops discharging at a certain level, I think 30% or so, to keep capacity high. I’m not sure what the warranty on the battery is. I think 8 years, but that could be wrong.

    Slugsie, that’s a good point. I don’t know for sure that the EPA estimate doesn’t take that into account, but I suspect you’re right.

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  21. 21. priddseren 2:29 pm 09/24/2012

    While certainly an interesting article it would be nice to see a study of various cars in many areas. Where I live the cost of electricity is so high thanks to California imposing a 400% tax on at least 2/3 of my electricity, charging this Volt would have cost me more like 32 cents per KWH. At my house that 2400 KWH mentioned here would have definitely been Tier 5 taxed assuming 218 KWH per month. This makes charging a volt signification more than the price of Gasoline where I live.

    In addition to this, and perhaps the author accounted for it but I have seen most measures of fuel used to produce electricity to be inaccurate. What is done is the assumption that coal has a specific amount of energy when burned, which must equal the KWH that can be produced. Which is true in a lab or if you burned coal in your back yard to produce electricity. However, more coal is actually used to produce electricity from a power plant, transformed up to high voltage twice to move the power over the grid and stepped back down at least twice to get it into your house. All of this transforming and movement of power results in a significant loss of power, resulting in burning more coal or natural gas to generate the excess needed to move the electricity around. Once this loss is factored in, the supposed savings of CO2 production is lost.

    Obviously if the power is generated by nukes, hydro, solar or wind power then the savings is better at least as far as CO2 goes.

    In the end, hybrids are likely the best option. If this configuration of engine and motor were not the most efficient available, then train locomotives would not be using this and they do have a reason to find the most economic engines available.
    Charging off the grid though is not going to do anyone any good. We should be working to remove the grid not using it more. I suspect if people in this article had a small natural has powered generator, a fuel cell or even some solar panels or a combination of the three, then that Volt would have been charged by onsite power generation, which is cheaper and uses less fuel to produce that same 218 KWH per month. It is always cheaper and easier to move fuel around than electricity.

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  22. 22. pjwood 11:32 am 09/25/2012

    EPA overstates EV carbon emissions, if we are to compare with “at the tailpipe” CO2 production, using gasoline. Everyone should walk around knowing the “20 lbs per gallon” statistic. The easy, apple to apple, comparison if doing so, is to tally CO2 production, at the flu stack. Most spew about 1,800 lbs, per MWH.

    Per KWH, that’s 1.8 pounds. Use that against the 20 pounds per gallon rule of thumb, and you’ll find that most of the common EV’s achieving 3 miles per kwh, equate to the carbon footprint of a 30 mile per gallon gas fueled car, SO LONG AS THE EV IS RUNNING ONLY ON COAL. when presented with fuel mix, obviously weight the figures down and factor natural gas in at half the CO2 footprint of coal.

    There are too many variables in power transmission, and oil refining and transport, to easily compare the carbon footprint of these two processes. That EPA is providing guidance that does, is pretty sad in my opinion. A 1.336 pounds per KWH value is far higher than what a 45% Ngas / 35% coal mix would produce at the plant. Should be closer to = (.35)(1.8)+(.45)(.5)(1.8), or 1.035 pounds per KWH.

    The EPA’s new Source Performance standard can be a check on these numbers, if you consider that the 1,000lb per MWH ceiling, proposed, has already been judged by some less-efficient natural gas electricity producers as the rate at which they sometimes emit..

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  23. 23. danair 5:10 pm 09/26/2012

    Great blog post. I’m an engineer with the Union of Concerned Scientist and the same questions about electric vehicle emissions and charging costs led me to co-author a report State of Charge which you can find at http://www.ucsusa.org/EVfacts .

    Our analysis breaks down global warming emissions from charging electric vehicles by the different electricity grid regions in the US. We found that even on the dirtiest electric grid in the country, an EV is responsible for about the same amount global warming emissions as a 34 mpg gasoline vehicle. In the cleanest grid regions, emissions from EVs are comparable to a gasoline vehicle achieving well over 80 miles per gallon.

    We also looked at charging costs for major cities across the UCS finding that driving on electricity is cheaper than gasoline – saving driver 50 to 85% compared to the average new compact gasoline vehicle and $3.50 per gallon gasoline.

    Check out chapter 4 of the full report for a specific analysis of the Chevy Volt, Mitsubishi i, and the Nissan Leaf.

    I also posted a blog on how emissions are expected to change by region over the next 15 years.
    http://blog.ucsusa.org/future-state-of-charge-how-clean-will-electric-vehicles-get/

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  24. 24. MrSustainable 9:11 am 09/27/2012

    My Volt is charged largely from our 5.3 kW solar array which removes the whole issue of dirty fuel source. I post live and historical information about my miles driven and energy used etc. on my web page: http://www.arttec.net/Chevy_Volt/index.htm

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  25. 25. selrachj 3:04 pm 09/27/2012

    Likewise, our solar panels charge our all-electric Leaf. We have a 7kw system (now 6 years old) and even with the Leaf, we pay only a few token dollars annually to SDGE, our California electricity supplier. At around $25,000 after rebates, I couldn’t be happier with the Leaf. One odd thing — filling up our other car with liquid fuel now seems bizarre and primitive. Some kind of psychological shift has taken hold. I’m fairly sure this makes economic sense, but most people don’t run their lives according to the economics – they do stuff that feels good. Driving an all-electric feels exceptionally good.

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  26. 26. obusmu 3:05 pm 09/27/2012

    As for the question about miles per dollar or cents per mile, I would like to mention that in Europe (I live in Norway) we always give fuel consumption as amount of fuel per distance (litres per 100 km). It was somewhat confusing to me when I first came to USA that the consumption was given as miles per gallon. It was even more confusing to the German car manufacturer BMW. In an advertisement in Time (possibly also in Scientific American) the stated that their new car coud do “fifty miles per hour at zero miles per gallon”. The car had an engine that was completely shut down when running a steep downhill, and in the European advertisement, they wrote zero liters per km, which was what they rather unsuccessfully translated into American English. Sci, Am. Printed a facsimile of the advertisement under the title “The ultimate gas guzzler”

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  27. 27. jerryd 4:08 pm 09/27/2012

    21. priddseren is a troll, possibly a paid one by big energy and his post has so much misinformation it’d take too long to correct it.

    If your dad buy windpower then it has little CO2. His money pays for it and should be credited with it.

    As for Coal it’s down to 32% of grid power and dropping fast.

    While it’s hard to directly compare MPGE because every site has different electric sources, you did well other than the above.

    My lightweight Harley size trike and sportwagon EV’s get about 250 and 600mpge. So good I can’t notice it on my electric bill even though it’s only $20-45/mo.

    What we really need is composite stronger than steel body/chassis that weight 50% of steel ones. My sportwagon EV only uses 70-100wthrs/mile because of this and good aero. These could be mass produced for under $15k using medium tech composites.

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  28. 28. KenThomas 8:53 am 10/11/2012

    It is interesting how the largest percentage of posters to forums like this have no actual experience with the subject of the topic. Additionally, there is a near linear correlation to the degree of negativity to the experience level of the poster. All kinds of “studies” are presented, using carefully selected data from external sources to prove the posters opinion.

    Having said that, I must acknowledge that being human; I also cannot prevent personal bias. My study data, however, is derived from two years and 26K miles of direct daily experience with a Chevy Volt, the money paid to buy it and the energy cost to drive it.

    My wife and I purchased Chevy Volt #644 in January 2011. Combining electric and gas expenses together, our Volt has consumed $40.00 per month over the 26K miles it has covered in its first two years. When deciding to buy the Volt, we expected a very tight budget for a lot of years to pay for it. Now, two years later, we are pleasantly surprised that it is considerably less expensive than we expected – less expensive than the sticker price implies. In fact, we are now banking more money with our Volt, while driving more miles, than with our previous 25K sticker priced gas car. That is because we are only paying monthly car payments, instead of monthly car payments plus a near equal amount for gas.

    However, that is all just “icing on the cake”. It is not the primary reason we bought our Volt. I like it because of the engineering. I like that GM did not take the minimalist route to fuel efficiency as with other hybrids. The car is built on a very heavy, truck worthy, frame and suspension (we have hauled several tons of rock, brick, concrete, fill dirt, and construction material in 800 to 1,000 lb. loads, for an extensive landscaping project, with no noticeable drivability performance reduction or suspension overload). My wife likes the hatchback load capacity, solid drivability and comfort. We both like the sustained hard acceleration from takeoff to 100 MPH (My wife loves the thrill of street racing the Volt against sports cars). We both bought our Volt because we like electric power. We hope electric will be the future and the Volt is a perfect “backwards compatible” electric vehicle. We like electric power, because it requires the least number of conversions from generation to traction. It is the easiest energy to produce from the largest number of sources. It is not a controlled pump fuel. I can generate electricity at my house. The source of electricity can be free as the wind and sunshine. For the most part, I like it because it is my life and my career. So, due to my electric bias, I was willing to pay more for our Volt, but as it turns out we are paying less.

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  29. 29. gdwolf 10:55 pm 11/6/2013

    One variable That didn’t come up was the energy cost of refineing, transporting and storage of gasoline. I think the whole question has been grossly overanalyzed. The grid can be cleaned up, ice vehicles can only be cleaned up so much. Given that 60 to 70 percent of the energy used by conventional vehicles is wasted as heat; you would be better off using gas to power a generator.

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