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How you charge an EV has huge environmental impacts, study shows

Research from the University of Michigan shows that smart charging strategies can preserve a vehicle's battery and dramatically reduce emissions.

Craig Cole Former reviews editor
Craig brought 15 years of automotive journalism experience to the Cars team. A lifelong resident of Michigan, he's as happy with a wrench or welding gun in hand as he is in front of the camera or behind a keyboard. When not hosting videos or cranking out features and reviews, he's probably out in the garage working on one of his project cars. He's fully restored a 1936 Ford V8 sedan and then turned to resurrecting another flathead-powered relic, a '51 Ford Crestliner. Craig has been a proud member of the Automotive Press Association (APA) and the Midwest Automotive Media Association (MAMA).
Craig Cole
2 min read
2022 Ford E-Transit - delivery
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2022 Ford E-Transit - delivery

Electric delivery vans are slowly becoming more popular among fleet operators. 


What's the largest source of greenhouse gas emissions in the US? If you guessed the transportation sector, you'd be right. This is why automakers are scrambling to electrify their product portfolios. But beyond personal cars and trucks, huge environmental benefits can be reaped by switching fleets to battery-powered delivery vehicles.

According to a study released on Monday by the University of Michigan, the lion's share of lifetime emissions for electric delivery vehicles -- between 50% and 80% -- are the result of charging. Using renewable energy sources for juicing these vehicles is one way to make a huge environmental impact and meaningfully reduce pollution.

According to researchers, when both charging and battery degradation are taken into consideration, optimized charging could reduce greenhouse gas emissions by up to 37%. Recharging vehicles in a way that doesn't shorten their batteries' lifespans can have an impact, too. Keeping batteries healthy means they don't have to be replaced down the road, which opens a whole separate can of worms.

Manufacturing batteries is no easy task. They need untold amounts of engineering and testing to develop; special elements and minerals are required, which have to be extracted from the earth, often in areas far away from where batteries are manufactured; and then all of these raw materials have to be refined and assembled into a working battery pack. Many people don't realize it, but there are loads of emissions associated with simply building batteries. (There are plenty of emissions in the refinement and transportation of fossil fuels too, on top of burning them in engines, but that's a different matter.)

GM BrightDrop - van
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GM BrightDrop - van

Companies like Amazon, FedEx and UPS are transitioning to electric delivery vehicles. 


All this sounds a bit ominous, but there is good news. According to the study "…even in the most carbon-intensive regions of the United States, electric delivery vehicles resulted in fewer greenhouse gas emissions than their gasoline or diesel counterparts." Significant carbon reductions are coming in the future, too, as companies like Amazon, FedEx and UPS transition to electric delivery vehicles.

One major recommendation borne of this research is that operators with fleets of electric delivery vehicles take battery degradation into consideration: Charge these vehicles intelligently to prolong the life of their batteries. This is good for both the environment and the bottom line.

Not fully charging a vehicle can help extend battery life, too. So-called "sufficient charging" puts just enough juice into the pack for the day's work. When vehicles sit around with a 100% state of charge it can cause batteries to wear out more quickly.

Another suggestion is that operators consider the source of the electricity used to replenish their vehicles. You can drive the greenest EV ever engineered, but if you charge it with a homemade generator that burns shredded tires it ain't going to be very environmentally friendly. Seeking out renewable energy sources will have a much greater environmental impact than blindly recharging electric vans off the grid.

GM revealed its new BrightDrop business unit at CES 2021

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Watch this: BrightDrop is GM's new logistics business