EV’s dirty secret

Manufacturing takes an incredible toll on the environment and releases tons of greenhouse gas emissions every year. Making cars is no exception. In fact, when you look at carbon emissions alone, manufacturing an EV is actually worse for the planet than making a conventional car. This comes down to the effects of mining, transporting, and refining battery materials. 

But EVs do “break even” with gas powered cars over time. How long does it take to reach the break even point? Does it matter where you live and how you power your car? How much does electricity generation matter?

EV lifecycle emissions

When people think about car emissions, most think about tailpipe emissions - aka the smog that comes from the back of your car as you drive.

However, climate scientists look at the bigger picture when it comes to emissions. That means in addition to operational emissions, scientists have to consider the total lifecycle emissions associated with producing and distributing cars and their fuels. Lifecycle emission assessments may also be called “cradle-to-grave” since they start with the “birth” of the car and end with its “death.” This sort of calculation adds up all the ways that emissions can be associated with a car - manufacturing, operating, upstream emissions, and end of life. 

1 - Manufacturing Emissions 

At the beginning of a car’s life cycle, there are the emissions from vehicle manufacturing. In addition to the carbon emissions from the manufacturing process, raw materials needed to make electric vehicle batteries, like cobalt and lithium, are acquired through difficult and hazardous mining operations, many linked to human rights violations. The massive amount of groundwater required for battery production also means making electric cars can use 50% more water than manufacturing traditional combustion vehicles. 

As an example, manufacturing an average gas powered sedan creates about six metric tons of carbon dioxide emissions, but manufacturing an electric vehicle of the same size creates more than 10 metric tons of carbon dioxide emissions. As EVs become more popular, the problem is getting more attention, and even EV automakers are calling to decarbonize supply chains.

So, electric cars start “in debt” when it comes to their carbon emissions - either 10 metric tons in total, or 1.3 to 2 times more greenhouse gasses than ICE vehicles, depending how you’re accounting. 

• Gas car - 6 to 9 metric tons CO2
• EV - 11 to 14 metric tons CO2

Can EVs really be the better choice once they are on the road?

Operational Emissions

Operational emissions are the thing most people think of when they think about auto emissions - the stuff coming out of your tailpipe. It’s a big phrase for a simple concept. It’s also where EVs rapidly catch up with gas cars in the race to clean transport. 

When it comes to carbon accounting, the very best thing about electric cars is that they produce zero tailpipe emissions when they are used. No smog, no NOx, nothing to make the air around them difficult or dangerous to breathe. 

On the other hand, gas cars produce a lot of tailpipe emissions - more than 50% of their lifetime emissions come from day to day use. For a single mile, gas cars produce about 400 grams of CO2, and 8,887 grams CO2 per gallon burned. Over their entire lifetime, assuming 11,000 miles a year and a 12 year life, that’s 46 metric tons of CO2. 

• Gas car - 6 + 57 metric tons CO2 = 63 metric tons CO2
• EV - 11 metric tons CO2

2 - Upstream Emissions

Although operational emissions seem simple, there is more than meets the eye. Regardless of how your car is powered, you need to get the fuel, and there are carbon emissions associated with getting and transporting that fuel. 

For gas cars, this means the emissions that come from drilling for, refining, and transporting gas. For EVs, there are emissions associated with generating electricity from natural gas, coal, or, preferably, renewable sources.

As EV skeptics love to point out, non-renewable fuel still accounts for 78.5% of electricity production nationally, so producing electricity is not yet that clean. Globally, it is still twice as “dirty” as refining gasoline, even though there are a lot of regional variations. Countries or states that have a lot of renewable energy produce “cleaner” electricity than those that rely heavily on natural gas or coal. 

As of 2023, a report from Polestar and Rivian put the upstream emissions of a gas car at around half that of an EV. For the life of a car, this report estimates 13 metric tons CO2 for a gas car, and 26 for an EV. 

• Gas car - 6 + 57 + 13 metric tons CO2 = 76 metric tons CO2
• EV - 11 + 26 metric tons CO2 = 37 metric tons CO2

Even though generating electricity can be dirty, it still generates less CO2 than the operational emissions of a gas car. 

Moreover, it’s important to consider EVs one step in the electrification future. Producing gasoline will never be renewable or carbon-free, and will probably never “cost” much less than 13 metric tons CO2. But, the electric grid can and will get cleaner. As the world relies more and more on clean energy, upstream emissions for electric vehicles will be reduced. When you power an EV with renewable energy, like solar or wind power, upstream emissions diminish. (To learn more about upstream emissions where you live, check out the EPA’s Beyond Tailpipe Emissions Calculator.) 

3 - End of life

EVs are still fairly new technology. There is a lot of optimism around the reuse and recycling potential for their batteries, but most cars - and their batteries - are still on the road and in good shape. Other than that, electric cars are basically just very simple cars with fewer moving parts. Most carbon accounting, including the one illustrated above, assumes that EVs with have the same carbon impact as gas cars when it comes to end of life. 

• Gas car - 6 + 57 + 13 metric tons CO2 = 76 metric tons CO2
• EV - 11 + 26 metric tons CO2 = 37 metric tons CO2

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So…how bad are EVs?

To accurately compare the impact of gas cars and electric vehicles on the environment, we need to examine the complete lifecycle of the car - from manufacturing, to use, to when the cars get taken off the road. 

Gasoline powered vehicles start with manufacturing emissions, and then release 8,887 grams of carbon dioxide in tailpipe emissions for every gallon of fuel burned. Electric vehicles produce zero tailpipe emissions, but do have associated upstream and manufacturing impact. So what does this look like over an average lifespan of a car?

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Over the course of its life, a new gasoline car will produce an average of 410 grams of carbon dioxide per mile. A new electric car will produce only 110 grams. 

Do electric cars ever catch up?

Since EV manufacturing creates more emissions than ICE manufacturing, but their operational emissions are lower – how long does it take for an electric vehicle to “break even” with a gas powered car? When are electric cars really "cleaner" than gas cars?

About 1.4 to 1.9 years.

Yup, it takes less than 2 years for electric vehicles to catch up and start surpassing gas fueled cars when it comes to lifetime reduction in emissions. 

Fuel efficiency plays a significant role in this calculation. The average efficiency for gas cars in the U.S. is about 25 mpg. The average efficiency for an EV in the US is near 100 mpgE, or miles per gallon equivalent. It takes a lot less energy - around four times less - to go a mile in an EV. This is how an electric vehicle with average efficiency will be “cleaner” than the average gas car in less than 2 years, no matter where you live. 

Note that an extremely efficient gas vehicle, like the Mitsubishi Mirage, with a combined fuel efficiency of 39 mpg, can keep its lifetime carbon emissions below that of the average EV for 3-6 years, depending on the output emissions rate of your electric grid. However, the EV will eventually be cleaner, even if it takes a bit longer. 

The really interesting comparison is between fully battery electric vehicles and plug-in hybrids. Hybrids start out with less of a manufacturing emissions debt than BEVs, since they have smaller batteries. Being able to switch between fuel sources allows them to mitigate the emissions rates from both. Depending where you live and how long you plan to keep your car, a plug-in hybrid could be a greener choice than a fully electric vehicle. A PHEV on the cleanest electric grid generates the least amount of lifetime carbon emissions out of any vehicle type. 

Note: this calculation hinges on the PHEV being plugged in and used in EV mode whenever possible. 

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Beyond Carbon

Carbon pollution isn’t the only concern with regards to protecting the environment. A 2019 meta-analysis found that noise pollution from human activity should be considered a serious form of environmental change. Noise pollution hurts land and sea animals, and our health, as well. The World Health Organization strongly recommends reducing noise levels from road traffic to below 53 decibels during the day and 45 decibels at night. A busy street is about 75 to 85 decibels, loud enough that extended exposure can permanently damage hearing. Electric vehicles, on the other hand, are so quiet federal law requires EVs to generate artificial sounds when at low speeds to ensure pedestrian safety. Electric cars can be an important part of keeping our communities peaceful and quiet.

EVs are also important for keeping the air in our local communities clean. Research shows more electric vehicles on the road improve air quality, regardless of how the electricity is generated. Many health conditions are worsened by ozone, particulate matter, and other pollutants, and the impacts of air pollution disproportionately affect minorities and disadvantaged communities. Choosing an EV means the air in your neighborhood, and your driveway, will be cleaner from day one.

Recent research has complicated our understanding of vehicle pollution, however. The environmental benefits of electric vehicles are unevenly distributed across demographics. And while driving an EV makes the neighborhood around it cleaner, the neighborhood that generates electricity for that EV gets dirtier. One analysis found 91 percent of local pollution damages from driving an electric vehicle are exported to states other than the state in which the vehicle is driven. Their model was based on the electric grid as it was in 2010-2012, so it’s reasonable to assume the grid has improved considerably since. Even so, a national effort to transition to renewable energy sources is imperative to offset the emissions and environmental damage of electricity generation. Without major changes to the electricity sector, an increase in emissions from increased EV use could offset more than half the emission reductions from having fewer gas-powered vehicles on the road. The environmental impact of your vehicle is highly dependent upon where you live and how you get electricity or gasoline.

The green cheat code

The best way to reduce the environmental impact of a new car? Buy used! The battery and manufacturing processes are responsible for 35% of EV emissions. Buying a used EV reduces your carbon emissions to only the upstream emissions needed to power your vehicle. That’s about 1.3 metric tons annually, versus up to 5.8 metric tons for ICEVs. 

The next thing to clean up is electricity generation. With improving technology, we hope to rely on a greener national electric grid in the near future. Depending on where you live, this may be a reality already. But, many EV drivers are also able to install home solar and charge their cars, for free, using the sun. Gas car drivers will never have access to clean energy like that.

The other critical step is battery recycling, which will reduce the carbon footprint of battery manufacturing - especially mining and refining critical minerals. Companies in the US and abroad are already working on this problem, and governments are finding ways to financially incentivize battery reuse and recycling. Hopefully, this effort will continue to pick up steam and reduce negative environmental impacts.

Climate change is the biggest threat facing humanity. We need to act fast if we want a sustainable future. Fortunately, achieving net-zero emissions is possible - and adopting EVs is a critical step. We’ve already reached a tipping point for electric vehicle sales, paving the way for mass adoption.

There is no way to completely eliminate carbon emissions from personal vehicle use, not even fully electric vehicles. But when it comes to protecting our planet, we don’t need to be perfect. We need to be better. The car you choose could make all the difference.

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*Note on calculations:

Assumptions for calculations above include an average EV efficiency of 0.35 kWh per mile and 8,887 gCO₂e per gallon of gasoline burned. Assumes cars are driven 11,000 miles yearly. Tailpipe emissions for gas vehicles multiplied by a factor of 1.25 to account for emissions from gasoline production/transportation. Assumes PHEV tailpipe emissions are 60 g/mile, with 67.7% fully electric operation and 32.3% operation fueled by gasoline.

Upstream emissions calculations taken from the EPA’s Power Profiler. The "Lowest Output Emissions Rate" is the NYUP eGRID, and the "Highest Output Emissions Rate" is the MROE eGRID, which has the highest output emissions rate in the mainland U.S.A. Source. Maintenance emissions and end-of-life emissions factors included in Year 12. Source.