If you pay attention to car commercials, the electric vehicle transition will involve vast numbers of people trading in their gas-powered sedans, pickups, and hatchbacks for battery-powered corollaries. That’s all well and good. But in the fight against climate change, the most impactful electric vehicles won’t necessarily be the ones everyday consumers buy, but rather the vehicles that move in fleets, like rental cars, buses, and delivery trucks.

The argument for electrifying fleets is simple. Fleets of vehicles are purchased by institutions, companies, public school systems, and the government, in bulk. They can take far more trips in a week than a typical passenger car in a single day, which means that replacing one of these vehicles with an EV can have an outsized impact on reducing carbon emissions. Because these vehicles often travel on fixed routes, it can also be easier to set up a network of EV chargers to keep them powered. The overall idea is that by transitioning a series of vehicles all at once, fleets can lower overall costs and lay the groundwork for electrifying transportation at scale.

“Having electric vehicles on the road with these fleets, it creates that familiarity,” explains Katie Robinson, the programs and operations vice president at the Electrification Coalition. “It shows the commitment of the municipalities, the state governments, and these private companies.”

Rental car companies like Avis and Enterprise have already committed to this transition, at least in part, which will effectively give more people the opportunity to drive electric vehicles before purchasing them. Because these companies often sell their vehicles onto the secondary market after just a few years, this transition could also increase the number of used EVs available to consumers in the coming decade. Hertz, in particular, has already committed to buying 100,000 Teslas, along with 65,000 EVs from Polestar and up to 175,000 EVs from General Motors. These vehicles are a key part of the company’s plans not only to electrify its fleet, but also to establish new business models for the electric era. Those include everything from loaning electric cars directly to Uber drivers to renting EVs to corporate travelers whose employers are trying to cut down on their emissions and meet ESG goals.

“We’re really starting to see a significant impact on the ICE [internal combustion engine] miles,” explained Steve Shur, the vice president for government relations for electric vehicle strategy at Hertz. “Uber drivers who are working full time in this capacity are spending a lot of time on the road.”

Electrifying delivery vehicles could also have a disproportionate benefit. These medium- and heavy-duty vehicles represented less than 10 percent of vehicles that were registered in 2020 but accounted for 26 percent of the transportation sector’s greenhouse gas emissions. Last-mile delivery tends to take place throughout the day, so replacing these internal combustion vans and trucks with other vehicles will cut down on the tailpipe emissions released into communities, and possibly noise pollution in those areas, too. (Because EVs don’t have internal combustion engines, they’re noticeably quieter).

FedEx aims to convert to an all-electric fleet by 2040, for example, and UPS has invested in and committed to purchasing delivery vans from Arrival, a British electric vehicle firm. Amazon, meanwhile, has poured hundreds of millions into the EV startup Rivian, and eventually plans to buy 100,000 electric vans from the company. This transition could become even more promising as companies take advantage of new federal credits for medium- and heavy-duty electric vehicles, and as bigger electric delivery vehicles come onto the market. PepsiCo is set to receive the first Tesla Semis, the EV maker’s yet-to-be-released Class 8 trucks, later this year. The German company Daimler Truck, which makes Freightliner and Mercedes-Benz brand trucks, is testing its own hydrogen-powered trucks.

“Our conclusion is battery first. Little trucks, then bigger trucks. We’ll see how the battery technology goes,” says Mike Roeth, the trucking lead for RMI. “Then we’ll know where the mix will be between hydrogen fuel-cell heavy trucks and electric heavy trucks.”

One major bright spot has been the electrification of government-owned vehicles. Electrifying public transportation creates enormous carbon savings, since they make it possible for people to travel without needing to buy a car at all. Electrifying public transportation and school buses can also drastically reduce people’s exposure to air pollution. The Biden administration will spend about $1 billion to expand the country’s fleet of electric and low-emissions school buses, and has also committed to ensuring that all new light-duty vehicles bought for the government’s fleet are electric by 2027. The US Postal Service said earlier this summer that 40 percent of its new vehicles would be electric.

There are still challenges. The companies and governments buying EVs for fleets aren’t immune from the supply chain problems that have made buying all sorts of electric cars more difficult, and more expensive, during the pandemic. These vehicles can also require expanded new grid capacity, which requires new infrastructure. There’s also the massive expense of buying new vehicles and securing access to chargers, and then convincing fleet operators that the fuel savings are ultimately worth making the switch.

“Fleet buyers are really driven by economics. They use their vehicles a lot, and they’re a great tool. They’re not a status symbol,” explains Brett Smith, the director of technology at the Center for Automotive Research. “You’ve had a whole fleet of vehicles that your mechanics, your drivers, your whole system knows and understands. … That’s a big hurdle.”

At the same time, thinking about how EVs can be used most efficiently is critical, especially when carmakers are still scaling up production. While EVs present clear environmental benefits over internal combustion vehicles, they come with downsides, too. Electric vehicles depend on a noxious supply chain for raw materials that can create “neo-colonial” relationships between countries like the United States and the Democratic Republic of Congo and Bolivia. Continuing to rely on cars, rather than other forms of transportation, also means the continuation of the extraordinarily high number of vehicular deaths — this problem could get even worse as cars get bigger and heavier. Prioritizing infrastructure that primarily serves these vehicles means leaving people behind who cannot, or do not want to, use them.

Fleets are a small reminder that some of the biggest benefits of electric vehicles may come on a communal, rather than an individual, level. A Tesla bought as a status symbol by an upper-income family that already owns two other cars doesn’t do as much good as a Tesla that’s used throughout the day by an active Uber driver. Collective electrification could be much more effective, and signals that the EV transition should probably involve more than just switching out engines for batteries.

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