Published on September 19th, 2014 | by Zachary Shahan


Are Electric Cars Green? Of Course! And Getting Greener Every Day

September 19th, 2014 by  


Electric cars are much, much greener than gas cars (“gasmobiles,” as I like to call them). Even in the state with the dirtiest electricity grid (Colorado), electric cars charging from the grid have a miles per gallon equivalency of 34. The average new gasoline-powered compact car has a fuel economy rating of 28 mpg. (In the cleanest state, New York, the mpg equivalency for a standard electric car is 112.)

are electric cars greener map

However, even all of this is missing a few key points. One, a large percentage of electric car owners also have solar panels on their roofs. That makes for some super clean driving. Two, electric cars mostly charge at night, when there is often excess electricity generation occurring anyway, so they may be charging from the grid while not actually contributing any extra emissions. Three, electric cars get people thinking much more about their electricity usage, which gets many of them to install more efficient light bulbs and appliances as well as conserve electricity more. It’s apparently not that uncommon for an electric car owner to see their electricity bill drop after getting their electric car!

Anyhow, back to the news of the day. “Sixty percent of Americans now live in regions where electric vehicles (EVs) produce fewer heat-trapping global warming emissions per mile than the most efficient hybrids, according to an updated analysis from the Union of Concerned Scientists (UCS). In 2012, that number was just 45 percent,” UCS reported on Tuesday, as National Drive Electric Week was getting rolling.

Much of this improvement has come from the grid getting greener and greener. A solar panel is installed in the US every couple of minutes. Wind turbines are also being installed at a good clip. Coal power plants are being retired, and no new ones have come online this year. The grid is getting greener, which means that driving on electricity from the grid is also getting greener.

Aside from the grid getting cleaner, electric cars have also improved. Chris DeMorro, on EV Obsession, writes: “Another key figure is battery efficiency, which has improved about 5%, using on average 0.325 kWh per mile, which is the equivalent to using a toaster oven for about 20 minutes. This has helped states like Texas and Florida, where EVs in both states emitted the same amount of emissions as a 48 MPG car, cross the threshold by a hair to 51 MPG.”

More Stories:

8 Reasons Electric Cars Kick Your Car’s Boot

Electric Cars May Be About 50% On Their Way To Market Domination

Electric Cars 2014 — Prices, Efficiency, Range, Pics, More

Image Credit: UCS

Source: Planetsave. Reproduced with permission.

Check out our new 93-page EV report, based on over 2,000 surveys collected from EV drivers in 49 of 50 US states, 26 European countries, and 9 Canadian provinces.

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About the Author

is tryin' to help society help itself (and other species) with the power of the typed word. He spends most of his time here on CleanTechnica as its director and chief editor, but he's also the president of Important Media and the director/founder of EV Obsession, Solar Love, and Bikocity. Zach is recognized globally as a solar energy, electric car, and energy storage expert. Zach has long-term investments in TSLA, FSLR, SPWR, SEDG, & ABB — after years of covering solar and EVs, he simply has a lot of faith in these particular companies and feels like they are good cleantech companies to invest in.

  • Cobi Yu

    Would be interesting to see the full lifecycle emissions analysis presented in the same way that this article does. This includes all the emissions produced to manufacturer each type of car including batteries, gasoline and their respective recycling impacts.

  • BetelgeuseOrion

    why do these idiots take electricity generation into account for the MPG but ignore energy required for gasoline extraction and refining?

  • Will Toor

    One quibble – While we agree with the general conclusion that emissions
    from EVs are getting better as the cars themselves get more efficient and the
    grid gets cleaner, we disagree with the claim that Colorado is the state that
    would have the smallest emissions benefit from electric vehicles. This is inaccurate. A cursory look shows that many other states have a dirtier electricity mix.

    The UCS study not analyze individual states, but lumps multiple states together – states that may have very different emissions profiles. So if a state happens to be in the same region as Oregon and Washington, with their clean hydropower, they will show up as very low emission even if they are heavily coal dependent. In Colorado’s case, it is lumped in with coal heavy regions of Wyoming, Nebraska and New Mexico.

    The vast majority of electric vehicles in Colorado are in the Denver metro area, where their electricity mix is 56% coal, 22% natural gas, and 22% renewables. This makes EVs cleaner than a car getting 42 mpg. And, because Colorado is moving towards much cleaner electricity, closing coal plants and adding renewables, by 2020 EVs in Colorado will be cleaner than cars getting 59 mpg. We have an analysis of emissions from EVs in Colorado available at:

    As a group that works on advancing EV policy in Colorado, it is really damaging to see this claim repeated each time that UCS updates its analysis.

    -Will Toor, transportation policy director, Southwest Energy Efficiency Project

  • Benjamin Nead

    Reminder: tomorrow, September 21, 2014, is the People Climate March in
    New York City. Many cities around the country are holding their own versions
    of this . . .

    Tomorrow likewise, is the cap off day for National Drive Electric Week,
    which is also a multi-city (and, now, international) event . . .

    Here in Tucson, we’ve combined the two . . .

  • JamesWimberley

    The diurnal variation of carbon intensity – lower at night (wind and nuclear baseload) and at noon (peak solar), higher in the early morning and especailly the evening – is calculable, and worth doing for somebody with the resources. As a back-of-the envelope rough cut, take California. Peak load is around 33 GW, trough 23 GW: about 2/3 of peak. Renewables provide about 15% of load on average; say 10% is wind and geothermal. But you can up this to 15% for a car charged at night.

    • Bob_Wallace

      Once we start “smart charging” EVs, allowing the charging times to be determined by the gird, we’ll be able to add a lot more wind and solar without wasting/curtailing or storage.

      That will mean a lot more renewables on the grid during high demand hours and the ability to use less fossil fuels.

      • GCO

        Definitely. My car is parked ~23h/day and charges for maybe 3h, but I don’t care which 3.
        I’d much rather have the system choose some “greenest hours”, e.g. when wind peaks, than some fixed arbitrary time like 2 to 5am, however grid-friendly this might seem right now.

        • Bob_Wallace

          “much rather have the system choose some “greenest hours””

          And give you a sweet rate for your kWh. Your car would be dispatchable load which has value to the grid.

          Even if the grid doesn’t have cheap electricity to sell the ability to stagger charging, thus avoiding bringing peakers on line is worth a lot. Especially with merit order pricing.

        • The UK actually has a sweet tool that lets them see how green the grid is at any particular time. We’ve had commenters here noting that they wait until it is relatively green to charge their EVs. 😀

  • Brokelyn

    So Mr Musk should start offering SolarCity roof panels with the purchase of their Tesla. It would be a whole package for zero emission driving.

    • GCO

      First, no it’s not necessarily a nice “whole package”:

      More importantly, hopefully Model S buyers know better and will purchase their PV system instead of leasing it.
      And who knows, if one of the reasons they went for a Tesla in the first place was to support American jobs, they might prefer domestic solar as well, something SC doesn’t offer.

      • CMCNestT .

        Solar City leases as well as sells solar panel packages.

        SC currently builds a small number of panels in CA and is building a factory in Buffalo capable of manufacturing 1 gigawatt worth of solar panels with a conversion efficiency of 21-24%.

    • Ha, they do, but as GCO notes, the result isn’t always swell. 3 parts to that series as far as I know, and the first two parts make SolarCity look clueless.

  • Kyle Field

    Interesting metric used by this infographic. I love that with residential solar, consumers can now control not only their transportation energy, but their home energy needs as well. Excited that there is a clear path for average folks to move off of petrol for personal energy needs 🙂

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