The ‘electric cars aren’t green’ myth debunked

Electric cars green myth

It’s time to bust this thing wide open.

‘Electric cars aren’t green’ is a great bit of counter-intuitive headline bait, but it’s bad maths.  This is how the argument goes, again and again…

Electric cars have higher manufacturing emissions than normal cars.  Electric cars also use electricity that has its own footprint.  And put together these two factors are a ‘dirty little secret‘ that negate any climate benefit of electric cars!

No.  Let’s clear this thing up once and for all.

It’s all about the juice

One of the most irritating things about articles discussing electric car emissions is the way it’s always very black and white.  In one corner you have the ‘zero emissions’ brigade and in the other the ‘worse than combustion engine’ crew.

But as ever, real life comes in shades of grey.

The reality is that even after you account for the bigger manufacturing footprint of an electric car it is all about the fuel mix of the power you use, the ‘juice’ if you will.

Using coal powered electricity electric cars do nothing to cut emissions, using natural gas electricity they’re like a top hybrid and using low carbon power they result in less than half the total emissions of the best combustion vehicle, manufacturing included.

In our recent study ‘Shades of Green: Electric Cars’ Carbon Emissions Around the Globe‘ we calculated grid powered electric car emissions in twenty countries. But we actually had data for quite a few more countries we didn’t include.

So let’s break out the data and put this thing to rest.

Mapping electric car emissions

The following map compares the carbon footprint of electric driving using average grid electricity in 40 or so countries.  The actual carbon intensity of electricity you use may differ from the national average for a number of reasons, but it’s a great starting point.

The results are shown in terms of grams of equivalent carbon dioxide per vehicle kilometer (g CO2e/km).  Each estimate includes emissions from vehicle manufacturing, power station combustion, upstream fuel production and grid losses.

The specs are based on a full electric vehicle, similar to a Nissan Leaf, using the 2009 average fuel mix in each country.  For each country vehicle manufacturing emissions are assumed to be 70g CO2e/km, based on a number of studies detailed in the report.

EV emissions by countryClick image to expand

Of the 40 countries covered in this map emissions vary from 70g CO2e/km in hydro loving Paraguay, up to a 370g CO2e/km in heavy coal using India.  The US average is 202g CO2e/km, in China it’s 258g and in Canada 115g.

In Paraguay virtually all the emissions are from vehicle manufacturing, as the power is incredibly low carbon.  Whereas in India the breakdown is 70g for vehicle manufacturing, 200g from power plants, 30g for fuel production and a whopping 70g for grid losses.

The colors in the legend split the countries into five different groups based on carbon intensity.  As you can see, even after vehicle manufacturing is included the carbon intensity of driving an electric car varies 5 fold based on the juice.

For a bit of reference, the average American gasoline vehicle is up at about 300g CO2e/km, while a new hybrid might manage 180g CO2e/km after you include vehicle manufacturing, fuel combustion and fuel production.

Compared to combustion vehicles

Because grams per kilometer is such a funny metric it is nice to convert these results to something more familiar.  Working backwards from the data we can estimate what type of conventional vehicle (if any) would produce similar emissions.

For want of a better phrase lets call this the ‘Emissions equivalent petrol car’.

EV emissions equivalent

Click image to expand.

Now the figures are much easier to get a grip on.

In coal heavy India, China, Australia and South Africa electric cars using grid power are just like typical gasoline vehicles, in the 25-30 MPGUS range.  In the UK, Germany, Japan and Italy they are as good as the best petrol hybrids, in the 45-50 MPGUS range. But in low carbon supply places like France, Brazil, Switzerland and Norway they are in a different league, averaging well beyond 100 MPGUS for equivalent emissions.

It is important to remember that the electricity you get might not match your national average for any number of reasons.  The night time intensity might vary, you might have solar panels or live in a country like the US, where the grid is actually a bunch of separate grids.  For example in Colorado a grid powered electric car is equivalent to about 30 MPGUS, whereas in California it’s up around 70 MPGUS.

For all the comparisons in this map the vehicle manufacturing of a gasoline car is just 40g CO2e/km compared to 70g CO2e/km for the electric vehicle.  This is because we have accounted for both a greater manufacturing footprint and lower lifetime mileage in an electric car.

If you are interested in the detail check out the full report.  It includes a breakdown of all figures, sensitivities to manufacturing, vehicle performance and comparisons to diesel vehicles.

Electric cars are as green as their juice

Critics of electric cars love to talk about manufacturing emissions and putting horses before carts.  But they never seem to offer any better solutions.  If they were waxing lyrical about urban densification, electrified public transport and the joys of bicycles their critiques would ring true, but that’s not what you hear.

Electric cars are relatively new at a commercial scale and are dealing with issues of cost, range and charging speed.  Each of which will be helped by improving batteries.  Despite this they offer enormous hope for reducing carbon emissions, improving local air quality and limiting noise pollution.

Electric cars are far from perfect, and there are plenty of valid ways to critique them.  But let’s not pretend that a gasoline vehicle can compete with an electric car in terms of carbon emissions.  It’s just not a contest.

Give an electric car the right juice and it crushes combustion engines.

 

Download the report here: Shades of Green 

Author’s note: in case you are wondering, I don’t own an electric car. We have an efficient Skoda diesel which is mostly used at weekends with 4 people in it.  My preferred mode of transport is my old dutch bike, which in terms of gCO2e/km trashes all comers (foodprint included).

30 Day Shrink Guide
  • Peter

    You assume, that there is a problem with carbon/Co2 When in reality without Co2 we would be all dead (Co2 is not a pollutant!). Its essential for all plants to grow, not to mention that they do better, with more of it out there.During the last ice age we had 12 times the level we have today, and everything did better, it helped to protect us from cold and starvation.Which is why some scientists argue that the levels are actually too low today. Not to mention that we have gone through 7 ice ages, and will again. It has to do with orbits around the sun, and not anything that we have done.
    I wish all those greentards would acually worry about pollution for a change. Not some wacked out Idea like carbon credits. That winds up costing us all more $$ and lines the pockets Government agency’s.

  • Érico Galindo

    Future is Eletric Vehicles, but not battery based ones, instead, Fuel Cell based ones.
    120L of Hydrogen = 650km of range or 100kw of power for sustaining a house for a week and no high amounts of toxic residue for biohazardous dead li-ion battery cells.

    • Nick Chanas

      The issue is that it will require a lot of energy (and water) to produce hydrogen since the gas cannot be found its pure form in nature (at least not in sufficient quantities to justify an industry being built on it). That makes it a lot less sustainable and more expensive than EVs (that can have batteries made of non toxic materials) fuelled by ”Greener” energies.

  • Bill Williams
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  • Chris

    The problem is the vehicles themselves. But the resources they use. Gas and electricity. Acid for the batteries coal for electricity and fossil fuels CO2 and all that junk. The processes needed to keep them going may do more harm. Lets say if most of the world began using electric cars now the grid is being drained and would need power. Either be nuclear power plants everywhere or coal. Pollution won’t end so long as people are around, thinking otherwise is foolish.

  • dreamer

    Why do we call more efficient emission energy sources “green” when they are clearly not? All will have a carbon footprint to some degree. My point simply currently pure “green” energy is a myth we simply don’t have the technology. But and my bugbear is, it doesnt solve our problem of rising greenhouse gas levels in our atmosphere just marginally reduces the rate of increase in the rise of these gases. Mind you I love the technology and we need to evolve our knowledge to get to a point where the reduction is significant. But it will not stop a net gain over time so for me it is more important to learn how to trap emissions and either change their state or store them efficiently and safely. So currently our premise that we have “green” energy is a pretty much a feel good furphy more environmentally friendly yes,exciting absolutely. It is a start and definitely has its place in the future particularly if we can develop the capture of co2 emissions. But not a solution to the problem at this point in time Just buying time maybe. Just my thought.

    • Lindsay Wilson

      While I agree with you in spirit, technically there is a pretty dramatic difference between the three major fossil fuel and any other source of power (renewables, nuclear, hydro . . ). In fact if you were to convert the global power, transport and buildings sectors to low carbon electricity you would more than halve global greenhouse gas emissions bringing them back towards the current absorption rates of the ocean and land sinks. This would stall the rise in radiative forcing, and limit warming to roughly 2C in the long run. So while there is technically no such thing a zero carbon (a phrase I never use), the difference between any fossil fuel and the rest is enormous. Most scenarios show that any chance of attaining 2C would entail both a dramatic shift to low carbon power and some form of sequestration technology (like BECCS)

  • Tom Materman

    It appears that you have overlooked New Zealand as a leader in nenewable energy sources. In 2012 it derived 70% of its energy needs from hydro, geothermal or wind turbines. It should also be afforded dark green status.

  • Isaac

    The title of this article is misleading to the point of being deceiving and ironically it is due to an incorrect analysis of the author’s own data!

    If the thesis is that a Nissan Leaf when charged with solar panels or hydro power is great for the environment that isn’t news to anybody.

    France is super green – BECAUSE THEY ARE 90% NUCLEAR! Electric cars powered by nuclear are great from a carbon and particulate pollution, with the obvious downside of nuclear waste. It is ironic that the “we love electric cars” and the “we hate nuclear power” crowds are almost completely overlapping in the Venn diagram.

    They tried to present electric cars as being equivalent to gasoline cars in the worst case (they have the coal countries in red labeled “average”). According to their own map an electric car in the US is similar to an “efficient” car….less than a “top hybrid”….indicating that if you care about carbon footprint you would buy a “top hybrid” instead of electric – confirming that electric cars are worse than gasoline.

    The further fallacy of all of this is that electric cars on the marker are super-light, super-small tin cans. To compare a tin can to an “average” American car is apples & oranges. If a Nissan Leaf has the same carbon footprint as a Chevy Impala something is terribly wrong. The real question is how efficient would a tin can sized car (like the Nissan Leaf) with a small diesel engine be – if it had a 2 gallon fuel tank (making it carry 500 miles of fuel is unfair when the electric cars don’t)…Or conversely lets look at a Chevy Impala sized electric carrying 500 miles worth of batteries.

    I can’t think of a better comparison than a plug-in hybrid run exclusively 1 way or the other. Then all things are equal – same car, same weight, same aerodynamic profile, etc. We can then compare the fuels directly.

    The next issue not addressed is that these maps highlight the current sources of energy in each country. The real questions is where would countries get additional energy from if their grids were being stressed (by all the charging)…Think of it similar to a marginal tax rate – what is the “marginal energy source”? Canada for example has a huge amount of hydro-electric power so they look very favorable. However it is safe to assume that all the economical hyrdo power has been tapped already so if Canada’s electricity demand doubled what would happen? It is irrational to think that they would simply double their hydro capacity. It is far more rational to think they will either build fossil fuel plants or nuclear to address the additional demand.

  • Hallgeir_Risenfald

    Havent read any of the comment so maybe it’s already there. You have to look at the electricity market on a global scale. If we in Norway use our clean electricity on å electric car we have that less clean electicity to sell to other countrys, so they have to pruduce more dirty electricity. So it does not really matter if you use clean electricity or not.

    • Isaac

      The question is what is the “marginal energy source”. If 1 more kWh of electricity needs to be produced (globally) where will it come from?

      Many low population density countries are very clean because they have a lot of hydro power. If those countries started depending on the electric grid instead of gasoline then more electricity would need to be generated. Are more hyrdo plants going to be built – I think not because all the viable hydroelectric power is currently being utilized for other purposes or to sell abroad.

      Presumably additional power needs to come from fossil fuel or nuclear.

  • Deivis Loren

    I do not agree with you. Electric cars called ‘green” because it do not emit CO2 gas … Your article is invalid.
    Išmetam?j? Duj? Surinkimo ?ranga

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