Electric scooters cause more pollution than they save, according to a first of its kind study published Friday.
Rentable e-scooters are marketed by companies across the country as the carbon free or Earth-friendly alternatives to transportation.
The study published in the Journal of Environmental Research Letters tested those claims.
It looked at the entire life cycle of the device from ground to scrap pile and found most of the time and under most circumstances scooters cause more carbon pollution than they save.
The biggest carbon burden for the industry are how long scooters live before being scrapped. Materials in the production off the scooters — like the aluminum frames and lithium ion batteries accounts for half its environmental impact.
There is widespread disagreement about how long scooters last. Companies have claimed anywhere from 9-18 months with current iterations, while media coverage has shown in some cases as little as one month. Authors tested claims based on them lasting six months up to two years.
“If you can get more miles of use, the per mile impact is going to be smaller,” said Jeremiah Johnson associate professor of civil engineering at North Carolina State University and co-author of the study.
What the scooter takes the place of is another big carbon impact question.
“If you are displacing walking or you are displacing a personal bike or if you are displacing public transit its largely going to be an increase in environmental impact,” Johnson said.
Their surveys found that scooters took the place of cars only a third of the time. San Antonio did a little better. Scooters replaced cars or car share about half the time in a city study. The same study said without the scooter San Antonio riders would have walked about 38% of the time.
When and how scooters are collected and deployed was another big factor. Trucks and vans used to deploy e-scooters were included in the industry’s carbon footprint. The study shows that often scooters are required to be removed each night regardless of whether they need to be charged. San Antonio requires they be removed each night from downtown.
The carbon impact of transporting the vehicles from Chinese factories to other countries, as well as the impact from recharging, were low.
There are things that can change the carbon impact equation. Companies can improve the longevity of their vehicles. There may be a way to decrease the impact of deployment by making batteries removable, he suggested.
In the end the study is a snapshot of the industry as it exists in 2019, something that will change dramatically even next year. Remember, Johnson said, these companies didn’t even exist two years ago.
“I don’t expect 2020 to look like 2019 and I think the scooter companies are going to change their operations and scooters will — the technology itself will evolve,” he said.