Tuesday, May 6, 2014

Volts For Oil: Gas Cars Burn Coal Too!

British actor and comedian Robert Llewellyn maintains a video blog called Fully Charged where he reviews electric cars and discusses all aspects of the plug-in vehicle industry. Llewellyn is an electric vehicle enthusiast and produces some really interesting and informative electric vehicle content in the series and I'm a big fan of his.

The latest topic he tackled is the "Long Tailpipe" argument which many people who do not support the switch to electric vehicles like to use in their argument against them. The Long Tailpipe argument basically states that electric vehicles are not zero emission at all, since the electricity that powers them comes from dirty sources like coal. Since EVs don't actually have tailpipe emissions, to be fair they say the real tail pipe stretches all the way to the power plant that generated its fuel, thus the long tailpipe.

There is no denying that the argument has truth to it. Much of the world's electricity is made by burning coal, and coal is dirty any way you slice it. Coal is in fact the dirtiest of all fossil fuels. When burned, it produces carbon dioxide and other emissions in flue gas. That contributes to global warming, creates acid rain, causes various respiratory illnesses and pollutes the water. However as Llewellyn shows, electric vehicles aren't the only vehicles that need electricity. Gas cars need it too, and a LOT of it in fact. Refining oil to make gasoline is an energy intensive process and the majority of energy used is - you guessed it: electricity.  

Llewellyn does a good job of explaining how much electricity is needed to refine gasoline, and that's just the refining process. He estimates that it takes 4.5kWk's of electricity to refine every gallon of gasoline. I've even seen that estimate quoted as high as 7kWh's per gallon from other sources. If you simply take the energy needed to refine the oil and put it into a battery instead of going through the whole process of refining, shipping, trucking and pumping (and the gas pumps need electric also) the stuff, you can power an EV to go 10 to 20 miles! Remember, that's just the energy used to refine the oil, nothing else. So if electric vehicle opponents want to bring up the long tailpipe argument, they then need to factor in the dirty coal emissions to every gallon of gas they burn.

However it's not as if every EV mile is powered by coal. In fact, here in the US coal fired power plants are closing all the time, and we now rely on coal for less than 40% of our electricity supply. Every year the grid gets cleaner as more renewables are introduced and outdated, polluting power plants are shuttered. This is happening as the supply chain of gasoline continues to get dirtier. How is that? That's because as we use up the current oil reserves, we are finding it harder and harder to find more. This is forcing us to use more energy to drill deeper, to go further offshore, and to even use unconventional sources like the Canadian tar sands. For example. producing one barrel of tar sands oil generates three to five times the global warming emissions that producing the same amount of conventional oil does and every day three million barrels of drinking water are used in its production. So you can see the supply chains for electricity and gasoline are moving in opposite directions. Electricity is getting cleaner, and gasoline is getting dirtier all the time.
My ActiveE and solar array. EV+PV is empowering and true zero emission driving

Plus, as the owner of an electric vehicle it is possible to make your own renewable energy to power your car. Three years ago I installed a solar array on my home and produce my own renewable energy for my EV. There is a great feeling of empowerment when you can make your own personal transportation fuel, and you know it is really zero emission driving. I've talked to many other EV owners who like me, installed a solar electric system shortly after discovering the world of electric drive. Solar powered electric vehicles are the future, we've just begun to scratch the surface of what is possible and I'm thrilled I've had the opportunity to live the future now. Anyway, back to Llewellyn's video. Take the four minutes to watch it. He does a fantastic job of explaining how gas cars are really coal powered cars too!


  1. This needs to be on 60 Minutes, or else it's just preaching to the choir. Sigh.

    1. I'm not the choir. What this doesn't prove is whether or not gas powered cars use less coal than EVs.

      And this comment is false:
      For example. producing one barrel of tar sands oil generates three to five times the global warming emissions that producing the same amount of conventional oil does and every day three million barrels of drinking water are used in its production.
      What's "conventional oil"... The oil we can no longer find?!
      And what in the world does drinking water have to do with anything?!

    2. So on one gallon of gas, my Prius can go about 50 miles fairly easily. According to this, I'm also consuming 4.5 kWh of coal fired (40% of the time) electricity.
      Ok so in the i3 (with the more efficient non-REx), it seems to consume about 9 kWh to go 50 miles. Hmmm...sounds like 2X the coal fired consumption!!

      I'm not an i3 basher... I actually want one. But let's not paint a greener picture than what the facts show.

    3. It seems like you are under the impression the claim here is that gas cars will always burn more coal than EV's. That isn't what we're saying. If you have an EV and power it exclusively from the grid, depending on were you live there is a very good chance you need to burn more coal to drive it then you would a gas car. However you then have only the emissions from the coal to claim. Your Prius for example has the 4.5 kWh's of coal generated electricity plus the tailpipe emissions from burning gasoline. And you can never reduce that. With an EV you can use electricity generated from renewable sources and have a true zero emission vehicle.

    4. But the article is comparing coal fired electricity consumption for electric vs gas fueled cars. Not tailpipe emissions -- that's another topic. Tailpipe emissions have CO2, sure, but car exhaust is actually cleaner than the incoming air! Read a study done by Volvo.
      Back to the topic-- the point is that the i3 will consume double the coal fired (for 40% of the US) electricity that a Prius will.

  2. The irony! A good article for EVangelism!!! Gas cars are coal cars too!

  3. Tom, thanks for the reminder why most of us are really into electric cars: not just because their cool, quiet, and different, but because their a step in the right direction of saving ourselves, the planet, and anything else hanging out on this beautiful spinning orb.
    Personally I would just as soon do my traveling on really quick and efficient mass transit and get to know my fellow citizens better but this would involve limiting the use of the singular personal auto. Unfortunately this probably won't happen in my lifetime as free market capitalism is rather adverse to limitations.

    1. This article actually says the opposite. You're not really saving yourself and the planet with an electric car. Please!!
      The i3 is a cool, clean, quiet, and convenient (eg, recharge at home)
      But the i3 consumes 2X the electricity (coal, nuclear, etc) that a Prius does. Is burning coal saving the planet? How about burning uranium and risking another Three Mile Island? If everyone drove an electric car, our chances of that would be doubled.

      Don't get me wrong. I love the i3 and will probably buy one. But it's no more "saving the planet" than an efficient gas car. Maybe more so. And let's not get into CO2... Just as many scientists who believe in global warming believe in an ice age instead.

  4. Great read! About half of our electric energy is supplied from coal in the US. The arguments I'm more frequently faced with are the environmental concerns surrounding battery production and disposal. Perhaps Llewellyn (Kryten!) can help me put this into perspective as well :)

    1. It's actually down to less than 40% as of 2013 and dropping every year as outdated coal fired power plants are being closed. Battery production is indeed a dirty process, I don't really have any data on it. However the disposal isn't really an issue. Just about the entire battery is recyclable. Also, the lithium is valuable and will be harvested from the batteries since they reach end of life, they will not end up in a landfill. Plus, once a battery degrades to about 70% capacity it's considered end of life for automotive use, but it is still a valuable asset and will be reused for load balancing and energy storage systems. I suspect a typical automotive battery pack will have it's cells in use for at least 20 years, most of which will be after it's removed form the car.

  5. Tom
    is your solar panel system interpolated with the grid or completely independent?

  6. Wow, 39 panels. Nice. Look like SunPower.

    If that house is efficient I suspect you are net zero, even with the car.

    See, I'm Green - with envy... :-)

  7. Its a nice try from an EV enthusiast but true evangelism only works if it's based on truth. I loved what he did in the 1990s series "Red Dwarf" but he is not comparing like with like.

    In the UK including renewables we put out just over 500g/kWh of CO2 from the grid (that includes the likes of me with my 3.91kWh PV Solar Array) every time I use beyond what the panels put out. In the UK we rarely better 20kWh for such a PV array and that's only for a few days in the summer.

    The rest of the year we mostly burn coal shipped in diesel ships (from the USA!) and gas shipped by diesel ships (from Qatar). Our local coal reserves are considered too dirty or uneconomic! Even if I could charge an EV in the daytime with my Solar PV (although most EVs don't like trickle charging hence the 16 or 32 Amp AC supplies), I would still need to power my fridge freezer and any electricity used in the house beyond the capability of the PV would rely on fossil fuels.

    Getting back to this video, using his figures my diesel pumps out just 14 g/km CO2 based on petroleum refining - actually it's a diesel and that requires much less refining! Anyway a Telegraph reporter once said if you cycle to work you put out 15g/km CO2 - based on the amount of toast consumed at breakfast!

  8. Very good article on true vehicle efficiency by the X Prize winners of the 100eMPG competition Edison2:


    Note how the EPA used Plug to wheels for EV efficiency:

    "Electricity use is similarly measured at the X Prize. Batteries are refilled at charging stations and metered for energy consumption: a “plug-to-wheels” formula, that accounts for losses in the charger, in the battery, and energy used by the engine to move the car. Certainly a more accurate representation than measuring the energy use motor-to-wheels, which leads to results all over the map, including some very high mileage numbers.

    A problem is that electricity is only an energy carrier and thermal conversion of energy is not considered in this calculation. In the real world for every BTU put into the American power grid for the production of electricity only 52% makes it to the plug. This 48% loss (from energy conversion and distribution) is not accounted for in the plug-to-wheel calculation.

    This plug-to-wheel calculation is important as there are many good reasons to shift toward an electric transportation future, such as new options, existing capacity, energy independence and remote emissions. However, a more accurate number for the Tata efficiency would be 40 mpg on gasoline and (134MPGe x .52) 70 mpg as an electric.

    This is a more efficient vehicle as an electric but the efficiency comes with costs: battery expense, range restriction and issues like grid capacity and resource allocation. Certainly a path worth pursuing, especially as the electric grid moves away from coal towards renewable sources of energy.

    Very complicated issues – what about the efficiency of distributing gasoline or ethanol? - and the X Prize is to be commended for adopting a clear, understandable standard in MPGe.

    But the fact remains: our Very Light Car – the most efficient automotive platform ever built – has crossed the 100 MPGe threshold."