Scientists have long settled the debate of whether electric cars are better for our environment than combustion engine cars—the answer is a resounding yes. In cities where adoption rates are high, air pollution has significantly declined. Yet the same tired discussion keeps resurfacing, sometimes even from the highest ranks of the world’s largest car company.

In an April interview with Automotive News that recently went viral, Toyota Chairman Akio Toyoda said that nine million electric vehicles have the same emissions impact as 27 million hybrids. That means one EV pollutes as much as three hybrids, according to him.

The chairman also expressed a strong desire to reduce emissions through what Toyota calls a “multi-pathway” approach: many different car powertrains, including more efficient gas engines, hybrids, hydrogen and, yes, EVs. 

It seems like Toyoda was referring to the emissions generated from production and charging in Japan specifically, where electricity has historically been generated from fossil-fuels. However, the share of renewables in the country’s energy mix has also been surging lately. Still, many media outlets jumped on Toyoda’s comments, framing them as “damning admission” and “carbon bombshell” to discredit EVs more broadly.

We took a deeper look to find out if EVs really generate more emissions than hybrids over their lifespan on a broader scale outside of Japan—especially here in the U.S.

Photo by: InsideEVs

Now, it’s true that comparing EVs to hybrids and plug-in hybrids (PHEVs) gets more complicated than a simple EV vs. gas car matchup. Regional electricity mix, driving patterns and battery usage all have a role to play. But let’s break it all down for clarity. (We reached out to Toyota to ask about how the company reached that conclusion, but did not hear back at the time of writing.)

The biggest anti-EV argument stems from the emissions generated during the mining, refining and processing of the raw materials used in high-voltage batteries. EV batteries use materials such as lithium, cobalt and nickel that require hazardous, water-intensive mining processes.

So when an EV rolls off a production line, it’s already born “dirtier” than the average gas or hybrid vehicle, for now. It comes with a bigger “carbon debt,” a term that researchers use to calculate the emissions vehicles gather before even hitting the road.

A research paper published in the scientific journal IOP Science says that gas and hybrid vehicles create six to nine metric tons of carbon dioxide emissions in their manufacturing, depending on the vehicle segment. EVs, on the other hand, generate 11 to 14 metric tons of CO2 emissions before going into the hands of customers.

But that’s only part of the story. Once EVs hit the road, they begin paying that carbon debt rapidly and their overall “emissions” decrease very slowly. Hybrids and gas vehicles grow their carbon emissions much faster. After a certain number of miles, an EV can potentially clear that debt entirely.

How long that takes, exactly, can depend on who you ask. A 2023 Argonne National Laboratory study found that it can take an electric car 19,500 miles to mitigate the emissions made during manufacturing. That’s less than two years of typical American driving, according to FactCheck.org. Another study in the journal Nature put that number higher, with carbon reductions beginning around 28,000 miles. Either way, considering how long Americans keep their cars, EVs become the far cleaner option over time.

Photo by: Toyota

Now, remember that not all hybrids are the same. Traditional hybrids like the Toyota Prius get a small lithium-ion battery pack and can drive on electric power for short distances before the gas engine kicks in. Plug-in hybrids (PHEVs) get a larger battery pack that owners can recharge. They can cover longer distances on battery power, usually between 30 and 50 miles, before the gas engine powers on. They both slot in between EVs and gas-only vehicles in terms of the carbon emissions they accrue in production.

As EV skeptics love pointing out, the power source matters, but not as much as you think. The U.S. was rapidly moving towards renewable energy until late last year. In fact, 43% of the country’s electricity mix at the end of 2024 came from clean sources, according to energy think tank Ember, as cited by Reuters.

But still, the electricity mix varies widely from state to state. West Virginia and Kentucky rely massively on coal-fired thermal power plants for electricity. California and Texas lead the country in terms of solar and wind output.

So yes, you can orchestrate scenarios where hybrids are cleaner than fully electric cars in certain conditions—but those cases are limited and shrinking by the day.

The 8,500-pound Chevy Silverado EV driving in West Virginia could be dirtier than a Toyota Prius that’s driving at slow speed for short distances, frequently reusing its battery, which gets charged by the engine and with regenerative braking. But when you do an apples-to-apples comparison, EVs are cleaner than hybrids even when the source of electricity is extremely nasty.

Photo by: Tesla

According to the Department of Energy’s emissions calculator, which takes into account tailpipe and grid emissions, a Tesla Model Y driven in West Virginia produces lower greenhouse gas emissions (149 grams of CO2 per mile) than a Toyota Prius Plug-In Hybrid (177 grams of CO2 per mile).

If you look at the CO2 footprint of the Model Y in California, which has a much cleaner grid, the Model Y will obliterate any hybrid or PHEV in terms of overall emissions. In Los Angeles, the Model Y only generates about 80 grams of CO2 per mile, whereas the Prius Plug-In Hybrid generates 130 grams of CO2 per mile—and that’s assuming that owners regularly charge the PHEV batteries, of which there’s little evidence.

And we haven’t even touched upon operational efficiency yet. Gas vehicles accrue emissions not only from manufacturing, but also the emissions associated with drilling, fracking and refining fossil fuels that are required to power them.

Plus, burning gas during combustion isn’t efficient—gas cars only convert about 20-40% of the fuel into energy, the rest is all thermal losses. EVs put more than 90% of their electricity to the wheels.

Due to all of these factors combined, the IOP study adds that EVs break even with their hybrid counterparts in terms of lifecycle CO2 emissions in just a span of 2.2 to 2.4 years of driving, depending on the vehicle segment. EVs break even with gas-only cars even faster, in just 1.3 to 1.6 years.

Crucially, the study also factors in the grid emissions. The study, which was published in March 2022, found that EVs were the cleanest in 2,983 U.S. counties, whereas hybrids were the least emitting option in 125 counties.

Photo by: Jeff Perez / Motor1

Several other reports, including those from the Massachusetts Institute of Technology’s Climate Portal and the EPA’s excellent EV Myths page, have concluded that EVs are cleaner in the majority of circumstances.

Finally, there’s the long-sought goal of battery recycling. Gas cars can end up in scrapyards where some of their metals may end up being reused. But companies like Redwood Materials, founded by a Tesla veteran, are springing up to completely recover and recycle batteries from wrecked and old EVs. If done right—and this will take time—it could lead to a circular economy where far fewer minerals need to be mined. The same can’t be said of gas cars.

So when Akio Toyoda said hybrids produce fewer emissions than EVs, he was probably referring to a dataset where all these factors are not taken into account, where grids are powered heavily by fossil fuels and hybrids are driven mostly in low-speed, stop-and-go traffic where regenerative braking and the small batteries are constantly at work. Or he was speaking purely about production.

Across the globe, the usage of renewable sources to generate electricity is soaring, which means EVs are only getting cleaner with time. Meanwhile, automakers are also developing battery chemistries that require fewer rare minerals and less carbon-intensive manufacturing—lithium iron phosphate (LFP) and lithium manganese rich (LMR) are good examples.

That means future EVs won’t just be cleaner to drive, they’ll start off cleaner, too, racking up less of the so-called carbon debt right from the factory floor.

Photo by: Toyota

That’s not to say hybrids and PHEVs are the enemies of clean air. In fact, modern hybrids are excellent options for buyers who aren’t quite ready to go fully electric. PHEVs, when regularly charged, can be driven much like EVs for daily commutes. And traditional hybrids still offer a major improvement over gas-only cars when it comes to fuel economy and emissions. Even modern gas cars are far cleaner than they were in decades past.

But in most cases, there’s little doubt that EVs outperform them both on efficiency, on emissions and increasingly, on overall sustainability. If we want a zero-emission future, it’s the most promising way to get there.

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