Popularly shared articles claim electric cars produce more greenhouses gases than internal combustion cars.

by Brian Dunning

Filed under Environment, General Science

Skeptoid Podcast #687

August 6, 2019

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Ever since electric cars first appeared on our roads, they've been a lightning rod in the battle between science and the fossil fuel industry. And once Tesla Motors began offering cars that were genuinely better in virtually every way than their internal combustion counterparts, this battle has risen to a fever pitch. Regardless of whatever else you want to say about it, at its core this debate is a proxy battle between those who accept climate science and those who reject it. As the evidence that electric cars are necessary to our future grows ever more substantial, attacks on electric cars have been symptomatic of the war against climate science — a position which, like a black hole evaporating at the very end of its life, spits toxic radiation more and more malignantly until it finally collapses out of existence with a final burst of scorn.

As the arguments that electric cars are too slow, don't have enough range, can't conveniently be recharged, etc. are all now things of the past, criticism of them has taken on a newer, smarter, more subtle character. Opponents have shrewdly concealed their arguments inside the moral foundations prized by the side of climate science, and formulated a narrative in which electric cars are the enemy of the climate. I say "shrewdly" because if this was true, and electric cars did make global warming worse, people like me would be the first to step up and keep our gasoline cars.

The core of this argument is that giant battery found in electric cars, up to 100 kWh as of this writing. Battery manufacturers add a whole other factory to the equation, and the mining needed to get the battery's chemicals adds yet another process. Both of these require infrastructure, trucks, air conditioning, employees who drive cars to work, and all kinds of things. According to this claim, adding the battery on top of the car's normal manufacture more than doubles the greenhouse gas emissions of producing the car.

The second part of this argument is that the electricity required to charge that giant battery as you smugly drive it around town comes from a conventional power plant (in most cases), and thus you're still driving on coal and oil, burning fossil fuels like everyone else; except that you also had that giant battery made, making you a worse contributor to greenhouse gases than the average Ford F-150 driver. According to this claim, each mile you drive contributes nearly as much greenhouse gas as a comparable internal combustion car.

And — make no mistake — both of these claims are more or less true, at least so far as the most basic facts go. The battery does mean that manufacturing your electric car contributes more greenhouse gas than manufacturing a comparable internal combustion car, and all that electricity used by electric car drivers did require burning fossil fuels to generate. What's not true about these claims is the numbers they give, and also the other important parts of the equation that they leave out. And what's really not true is their ultimate conclusion, that electric cars are worse for the environment. We'll get to the actual facts in a moment.

It should come as no surprise that the authors of these papers are typically not research scientists but rather think tanks — professional spin doctors who write quasi-research to promote whatever conclusion you pay them for. The two most significant such papers came from IVL Swedish Environmental Research Institute in Sweden and Ifo Institute for Economic Research in Germany, and were then published to websites dedicated to the denial of climate science like WattsUpWithThat.com and quasi-news websites aligned with fossil fuel interests like Breitbart. You don't find these reports in legitimate science news, and that should give you some sense of whether it's science or spin.

Regardless, if it's true that electric cars truly are the worse producers of greenhouse gases, then is that a valid argument against them, and that we should all keep our dino burners?

I saw a version of this same argument in an article advocating against the construction of nuclear power plants because of all the fossil fuel carbon emissions required during the construction — trucks and tractors and concrete and so forth. At first glance the argument makes sense, but not upon looking at the broader picture. Let's say you have to cross a river every day but you hate getting wet, so you consider building a bridge. But the actual construction would require that you stand in the water to do it, so you decide against it. Was that a wise decision? Of course not; because once you build it, you'll never get wet again. Similarly, we're already driving trucks and tractors and releasing more fossil carbon. Continuing to do so a while longer until the nuclear plant is built would enable us to power electric trucks and tractors once the plant is running. Long-term gains are almost always worth the short-term investment.

And so, by this same logic, even if all of the claims that the construction and disposal of electric cars and batteries mean a net increase in fossil carbon release, it would still be worth it; because no matter what, getting through that exercise is a necessary stepping stone to get from a fossil fuel infrastructure to an all-electric infrastructure. We usually have to do things badly to learn to do them well.

However, let us not beat around the bush, but jump straight to the truth. The claim that the lifecycle of an electric car produces more greenhouse gases than an internal combustion car is entirely the result of 50% carefully cherrypicked spin doctoring combined with 50% outright falsehoods. Here's the only way that argument can be made to work. If you buy an electric car with the biggest battery that requires the most manufacturing resources, if you drive your electric car in the least efficient way, if you drive your electric car in the worst climatic conditions for battery life, if you charge it only with electricity generated entirely by oil or coal, if you do not properly recycle the battery at the end of its life, and if you choose for your comparison the biggest-battery electric car against the smallest, lightest, compact internal combustion car: only then will it be true that the lifespan of your electric car generates more greenhouse gases than an internal combu— Oh wait, no; crunching the numbers again, the answer is still no. Even this worst case scenario substantially beats even the most efficient internal combustion cars. There's still one thing we have to do to before our electric car will actually be worse, and that's crash it and remove it from service before it's been driven anywhere. Because as soon as you and your internal combustion counterpart start driving, the scale tips the other direction.

Comparing all the numbers, there's one big difference between manufacturing an electric car and an internal combustion car, and that's the electric's big battery. Because of this, when both cars roll off the assembly line, it's true that the electric car's production has so far produced more greenhouse gases than the internal combustion — between 15% and 68% higher, depending on the size of the battery. But by the end of the car's life cycle, this relationship has been turned on its head. A midsize electric car has contributed only 49% as much greenhouse gas emissions as a midsize internal combustion car, and a full-size electric has contributed only 47% as much as its internal combustion counterpart. In short, internal combustion cars contribute twice as much greenhouse gases as electric cars, taking the entire lifecycle into consideration.

For those of you who might be surprised to learn that the electric contributes even half as much, the reason is that there are still fossil fuel power plants generating most of that electricity. The economies of scale realized by having one large power plant fueling many electric cars means electrics on even the dirtiest grid are still far cleaner than internal combustion cars, but those emissions are still there. On average, generating the electricity is responsible for right around 70% of your electric car's total contribution to greenhouse gases. But of course, that number can vary radically, depending on where you charge: from a dirty grid or a clean grid. One way to look at this is how many miles do you have to drive your electric car before you've made up for the excess greenhouse gases from manufacturing the car. Depending on the car and whether your grid gets it juice from renewables or from fossil fuels, that number (in the United States) ranges from about 3,700 miles to 39,000 miles. But once you pass that number — wherever your car sits in that range — you are officially cleaner than an internal combustion car.

There is more good news. All of the factors that drive these numbers are moving in the right direction, making this proposition better and better every day, shaving miles off that breakeven point. There are a few local exceptions, but overall the power grids are becoming cleaner each year with renewables continuing to grow. As we're beginning to see the first electric car batteries go into recycling, we're at the very beginning of realizing reductions in this part of the cost and impact of manufacturing new ones. Combined with constant improvements in manufacturing technology, the higher initial greenhouse gas contribution of electric cars will continue moving closer to that of internal combustion cars.

I'm not expecting anyone to take my word for any of this. You'll find all the references and further reading suggestions at the bottom of this page. If you're looking for the condensed version of the true science behind this, the best source I recommend is a 2015 position paper from the Union of Concerned Scientists titled Cleaner Cars from Cradle to Grave: How Electric Cars Beat Gasoline Cars on Lifetime Global Warming Emissions, available as a free PDF download.

In conclusion, I'd like to reiterate my river and bridge analogy. No matter how wet building the bridge gets you, it's to your advantage to build it. Also it's to your advantage to build it as soon as possible, as that's less total net wetting you'll have to take. So even if you disagree with every word the Union of Concerned Scientists has to say on this subject — which puts you in opposition to every publishing scientist in every relevant field — and even if you agree with every point of every argument made by the fossil fuel think tanks — it is still to everyone's advantage for each of us to switch to an electric car just as soon as we're able. There is only one way to disagree with this conclusion, and that's to deny the totality of climate science and human-caused global warming, which at this point basically means you've adopted Flat Earther thought processes. So if you are not a Flat Earther, go trade your car in on an electric as soon as you can, and let's all push these metrics even farther in the right direction for the good of everyone.



By Brian Dunning

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