Do Electric Vehicles Really Pollute More Than Gas Cars?

Welcome back to EV Myths Discharged, where we're trying to fight the good fight against disinformation. In this case, anti-EV disinformation. 

We've been drawing mostly from social media for sources of these myths because that's largely where they spread. We started by addressing the notion that you're totally screwed if you own an EV in an emergency. Since then, in the aftermath of Hurricane Beryl in Texas, we saw more evidence that it's EV owners who fare best in emergencies.

I also wrote about the myth that our nation's aging, struggling grid will implode if we shift to electric vehicles en masse. The truth, as it turns out, is that the shift away from internal combustion is something that grid companies have been preparing for for years.

This time, we're digging into something a bit broader in scope: environmental impact. Ever since the beginning of the EV, there's been a constant, nagging accusation that the things are actually worse for the environment than cars that burn fossil fuels.

The argument usually goes something like this: My state burns coal to generate electricity, and so, therefore, your supposedly emission-free EV is actually burning coal! Gasoline is cleaner for the environment than coal, and gas-powered cars don't need big, toxic batteries, so gas-powered cars are actually better for the environment! Checkmate.

The accusation of EVs being a net-negative for the environment has only been gaining volume lately, and that's despite it flying in the face of the truth. That's not my opinion, this is something that you can categorically and numerically prove, which I'll endeavor to do for you here.

As it turns out, it's pretty straightforward to calculate the environmental impact of not only a car but also of its battery pack and of the fuel that powers it, whether electricity or fossil fuel. 

Sourcing and Fuel Supply
The ability to calculate these findings is largely thanks to the EPA, which publishes comprehensive information about the emissions of every car available for sale in the U.S. In fact, the EPA has its own calculator that you can use to check any EV you want.

Regarding individual vehicle emissions, I'll rely on the EPA's rating for efficiency. For a gasoline-powered car, that's relatively easy because burning a gallon of gas emits the same amount of carbon in Kentucky as in California.

With EVs, it's a little more complicated because an EV's effective carbon output is largely dependent on where it gets its power. Recharge from some renewable energy sources, like wind or solar energy, and your EV will effectively have zero emissions.

But, believe it or not, even in places with minimal use of renewables, EVs are still cleaner for the environment. Let's dig into the numbers.

Locations
Location is so crucial here, so I'm going to start by picking two places in the continental U.S. since that's most relevant to most people. And I'm relying on data from the EPA Power Profiler, which has comprehensive data for every region of the U.S.

The first location is Wisconsin, selected not because of its ample supply of cheese but because it resides in the Midwest Reliability Organization East. This is the name for a section of the American grid, but not just any section.

This area of the U.S. gets just 15.6% of its power from renewable sources. The rest comes from a variety of fossil fuel sources, mostly gas and coal.

Now, the most efficient part of the U.S. is Alaska, which gets nearly 70% of its power from renewables (hydro, mostly). But, since I doubt many of you are tuning in from The Last Frontier, I'll stick with New York, which has the lowest CO2 emissions per megawatt-hour of any other U.S. region. 

Those are the high and low examples we'll work with going forward.

Cars
Next, we'll need a pair of comparable cars to show the difference here, one that burns gasoline and one that burns electrons. Let's say we're big spenders, and we want a big, luxurious sedan. A Lucid Air sounds awfully nice, and since we're comparing two regions that get snow, we're probably going to want all-wheel drive. 

So, let's go with a Lucid Air Touring, a dual-motor version with 19-inch wheels and a 92 kWh battery pack offering 425 miles of range and an efficiency of 24 kWh per 100 miles per the EPA. It starts at $78,900.

On the combustion side, we'll need something similarly all-wheel drive. It'll need to be quick and luxurious, too, to really compare. Let's go with the Audi S6, which, at 4.4 seconds to 60, is substantially slower than the Lucid, but its $75,500 MSRP lines up nicely.  

CO2 Per Mile
Everyone's familiar with a car's miles-per-gallon efficiency, and we're increasingly familiar with miles per kWh. But comparing the two can be a little complicated.

Don't worry, that's what I'm here for.

It'll be a lot easier if we bring both those figures into a single, comparable metric. Since we're talking about environmental impact, let's work in pounds of CO2 output per mile.

To start, let's figure out the Audi since that's a single figure regardless of where you drive it. The EPA has a combined 22 miles per gallon rating, which equates to 4.5 gallons per 100 miles, or 0.045 gallons per mile. Since one gallon of gas emits 20 pounds of CO2 when burned, we're talking about 0.9 pounds of CO2 per mile. 

Except that's not quite right. That ignores the CO2 emissions involved in the transport and delivery of that fuel. According to the Department of Energy, that adds roughly 25%, meaning the real, effective carbon output of an Audi S6 is 1.125 pounds of CO2 per mile. 

Now, let's look at the Lucid, which is admittedly going to get more complicated. The Lucid effectively uses 0.24 kWh per mile, but we must figure out the CO2 per kWh. In New York, with all its renewables, that's 0.2746 pounds of CO2 per kWh, which equates to 0.066 pounds of CO2 per mile.

What about those of you in Wisconsin? There, power generation is substantially dirtier, 1.4796 pounds of CO2 per kWh. That works out to 0.355 pounds of CO2 per mile. 

But we're not quite done. We factored in the transportation cost of fuel above, so we need to factor in transmission losses here. Per the U.S. Energy Information Administration, that's about 5% wasted in transmission, so the real figures are: 0.069 pounds of CO2 per mile in New York and 0.373 in Wisconsin.

That means, in the worst case, you're emitting less than one-third of the emissions per mile in the Lucid. That shows pretty quickly that the notion of EVs being just as bad as cars because they're effectively burning coal is completely false.

But hang on, there's more to the story.

Manufacturing
We need to factor in manufacturing as well. Yes, these cars are roughly the same size, but only the Lucid has a big battery pack, and there's a lot of CO2 emitted in its creation.

Exactly how much? Sadly, nobody knows, but there are lots of estimates, which are summarized in extensive detail over at CarbonBrief. On average, their estimate is roughly 220 pounds of CO2 per kWh of the battery pack.

The Air, remember, has a 92 kWh battery pack, so that means 20,240 pounds of CO2 are generated from creating that pack before you even drive it home. 

That seems like a huge deficit, the sort of thing that would put you in an eternal environmental debt when driving, but the reality is not so bad. Remember, the Lucid is outputting significantly less carbon per mile.

If you're driving in WI, based on our numbers above, it'll take you 26,910 miles to make up the difference. Consider that Americans, on average, drive 13,476 miles per year, and that means even if you just do a two-year lease, you're breaking even on a CO2 standpoint. Every mile that car is driven after that is a net positive for the environment.

Driving in NY? That figure is reduced to 19,170 miles total, or about a year and a half of driving. And, if you go with some of the estimates that show EV battery pack creation becoming more efficient in the future, that figure drops down to under 8,000 miles, or less than a year of driving.

Now, I want to be clear about one thing: EV manufacturing, specifically electric motors and battery packs, has some other unsavory environmental implications, mostly surrounding mining and recycling. This is a hugely important point and one that is all too often ignored.

We are not ignoring that here. Quite the contrary. That aspect of an EV's environmental impact is a massive topic in its own right, so we'll cover that one next time. Stay tuned. For now, we're focused on carbon.

Why EVs Are So Efficient
So, even if you live in the worst possible place in the continental U.S., driving an electric car is a net positive from a CO2 standpoint. It's not emissions-free, of course, but even if you drive a moderate amount, it is a step in the right direction.

How is that possible? It all comes down to the relative efficiency of electric motors versus combustion engines. While some rare examples do better, according to the EPA, the average efficiency of a gasoline-powered car is, at best, 30%. That means for every 10 gallons of gasoline you burn, seven of those gallons do nothing but make heat and smoke and noise.  

They are completely wasted, a fact that should bother absolutely every one of you, given how much gas costs these days.

The average EV converts over 77% of the electrical energy from the grid to power at the wheels. This turns the tables substantially.

Of course, we can't just look at the car's efficiency. We need to look at the efficiency of where it gets its power. A modern power plant, like a combined-cycle gas plant, is approximately 70% efficient.

That means the effective net efficiency of an EV using electricity generated from a modern natural gas plant is 54%, far more efficient than an average gas-powered car, even without factoring in the environmental cost of getting gasoline to your pump.

What if your power comes from coal? Well, you're looking at a rather less excellent efficiency of 33%. But, since even the worst states get only about half of their power from coal, you're still going to come out ahead, as our math above shows. 

But EVs aren't just about the status quo today. Coal-fired plants are being upgraded or retired in favor of more efficient natural gas plants. Meanwhile, access to renewables is increasing exponentially. Next year, New York State will complete the 339-mile Champlain Hudson Power Express line, which will bring 1,200 megawatts of renewable energy down from Canada and straight into the heart of New York City.

As we reduce our carbon emissions in the grid, the relative carbon performance of an EV will just keep getting better and better.

The Future
EVs aren't just for today. They're as much about creating a framework for the future. If we want to reduce global carbon emissions, we need to start eliminating sources. With something like 300 million cars running around on American streets, that's a lot of sources.

Shifting our transportation infrastructure to EVs doesn't eliminate the problem, but it effectively pushes it up a level, simplifying things. Now, instead of trying to fix millions of sources, you can focus on continuing to improve our power supply.

That's going to be a long, expensive road, but as you can see from the numbers above, even during this transitional period, switching away from a car that wastes 70% of its gasoline to make a bunch of noise and heat is already a net positive.

When it comes to carbon emissions, EVs are better for the environment. Case closed.