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SUVs are taking over the world—larger vehicle models made up nearly half of new car sales globally in 2023, a new record for the segment.

There are a lot of reasons to be nervous about the ever-expanding footprint of vehicles, from pedestrian safety and road maintenance concerns to higher greenhouse-gas emissions. But in a way, SUVs also represent a massive opportunity for climate action, since pulling the worst gas-guzzlers off the roads and replacing them with electric versions could be a big step in cutting pollution.

It’s clear that we’re heading toward a future with bigger cars. Here’s what it might mean for the climate, and for our future on the road.

SUVs accounted for 48% of global car sales in 2023, according to a new analysis from the International Energy Agency. This is a continuation of a trend toward bigger cars—just a decade ago, SUVs only made up about 20% of new vehicle sales.

Big vehicles mean big emissions numbers. Last year there were more than 360 million SUVs on the roads, and they produced a billion metric tons of carbon dioxide. If SUVs were a country, they’d have the fifth-highest emissions of any nation on the planet—more than Japan. Of all the energy-related emissions growth last year, over 20% can be attributed to SUVs.

There are several factors driving the world’s move toward larger vehicles. Larger cars tend to have higher profit margins, so companies may be more likely to make and push those models. And drivers are willing to jump on the bandwagon. I understand the appeal—I learned to drive in a huge SUV, and being able to stretch out my legs and float several feet above traffic has its perks.

Electric vehicles are very much following the trend, with several companies unveiling larger models in the past few years. Some of these newly released electric SUVs are seeing massive success. The Tesla Model Y, released in 2020, was far and away the most popular EV last year, with over 1.2 million units sold in 2023. The BYD Song (also an SUV) took second place with 630,000 sold.

Globally, SUVs made up nearly 50% of new EV sales in 2023, compared to just under 20% in 2018, according to the IEA’s Global EV Outlook 2024. There’s also been a shift away from small cars (think the size of the Fiat 500) and toward large ones (similar to the BMW 7-series).

And big-car obsession is a global phenomenon. The US is the land of the free and the home of the massive vehicles—SUVs made up 65% of new electric-vehicle sales in the country in 2023. But other major markets aren’t all that far behind: in Europe, the share was 52%, and in China, it was 36%. (You can see the above chart broken down by region from the IEA here.)

So it’s clear that we’re clamoring for bigger cars. Now what?

One way of looking at this whole thing is that SUVs offer up an incredible opportunity for climate action. EVs will reduce emissions over their life span relative to gas-powered versions of the same model, so electrifying the biggest emitters on the roads would have an outsize impact. If all gas-powered and hybrid SUVs sold in 2023 were instead electric vehicles, about 770 million metric tons of carbon dioxide would be avoided over the lifetime of those vehicles, according to the IEA report. That’s equivalent to all of China’s road emissions last year.

I previously wrote a somewhat hesitant defense of large EVs for this reason—electric SUVs aren’t perfect, but they could still help us address climate change. If some drivers are willing to buy an EV but aren’t willing to downsize their cars, then having larger electric options available could be a huge lever for climate action.

But there are several very legitimate reasons why not everyone is welcoming the future of massive cars (even electric ones) with open arms. Larger vehicles are harder on roads, making upkeep more expensive. SUVs and other big vehicles are way more dangerous for pedestrians, too. Vehicles with higher front ends and blunter profiles are 45% more likely to cause fatalities in crashes with pedestrians.

Bigger EVs could also have a huge effect on the amount of mining we’ll need to do to meet demand for metals like lithium, nickel, and cobalt. One 2023 study found that larger vehicles could increase the amount of mining needed more than 50% by 2050, relative to the amount that would be necessary if people drove smaller vehicles. Given that mining is energy intensive and can come with significant environmental harms, it’s not an unreasonable worry.

New technologies could help reduce the mining we need to do for some materials: LFP batteries that don’t contain nickel or cobalt are quickly growing in market share, especially in China, and they could help reduce demand for those metals.

Another potential solution is reducing the demand for bigger cars in the first place. Policies have historically had a hand in pushing people toward larger cars and could help us make a U-turn on car bloat. Some countries, including Norway and France, now charge more in taxes or registration for larger vehicles. Paris recently jacked up parking rates for SUVs.

For now, our vehicles are growing, and if we’re going to have SUVs on the roads, then we should have electric options. But bigger isn’t always better.

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