Julia Rosen, Los Angeles Times -
In March, Joe Hollingsworth hopped on a Lime scooter and zipped across the campus of North Carolina State University. At the end of the ride, a message appeared on the screen: “Your ride was carbon free.”
The pronouncement embodied the climate-friendly marketing of e-scooter companies like Lime and Bird. But it puzzled Hollingsworth, then a graduate student in environmental engineering, and his adviser, Jeremiah Johnson.
Sure, scooters don’t have a tailpipe. “But you have to think about the other things that are required to have the scooter ready, charged and available for you to use,” Johnson said.
So he and his students decided to tally up the full environmental impact of electric scooters over their lifetimes. The results, published last week in the journal Environmental Research Letters, suggest that e-scooters aren’t quite as eco-friendly as they may seem.
While travelling a mile by scooter is better than driving the same distance by car, it’s worse than biking, walking or taking a bus — the modes of transportation that scooters most often replace. That’s primarily because of the energy-intensive materials that go into making the vehicles, and because of the driving required to collect, charge, and redistribute them.
“That actual trip somebody’s taking on the scooter — that’s pretty green,” said Juan Matute, the deputy director of the UCLA Institute of Transportation Studies who was not involved with the study.”What’s not green is everything you don’t see.”
PROLIFERATION WOES
Dockless e-scooters, which you can unlock with an app and leave wherever you please, have flooded cities over the last year and half. In 2018 alone, people in the United States took 38.5 million scooter trips, according to the National Association of City Transportation Officials.
The technology is often touted as a solution to urban congestion and the vexing “last mile” problem — how to get people from their houses and offices to public transit lines. The proliferation of the two-wheeled devices has brought both joy and angst to urban residents, along with a fair number of fractured bones and head injuries, studies have shown. But until now, researchers had not conducted a rigorous analysis of the companies’ sustainability claims.
So Johnson and his students purchased a Xiaomi M365 scooter, which was used for the first generation of Birds, and took it apart. They made precise measurements of each component’s weight and calculated the greenhouse gas emissions associated with making it. They also looked at the resulting air and water pollution.
Those impacts were significant, the researchers found, especially for the scooter’s 13-pound aluminium frame and its 2-pound lithium ion-battery. Using their best estimates about scooter use and management in Raleigh, North Carolina, they found that materials and manufacturing accounted for roughly half of its global warming impact and an even greater proportion of its other pollution footprints.
Those results depend heavily on scooter longevity, which influences how many rides companies can get out of those parts. And urban life is hard on shared e-scooters.
They succumb to the everyday wear and tear of riding and recharging. There’s also rampant vandalism. People trash scooters for all sorts of reasons: for fun, out of frustration that they’ve taken over bike lanes and sidewalks, and because many are sick of the kinds of tech start-ups behind them. (In Southern California, scooters have been burned, broken and buried at sea.)
By some estimates, Bird’s first batch of scooters lasted about three to four months, and the newer Bird Zeros are said to make it about 10 months. However, one analysis by Quartz found that scooters in Louisville, Kentucky, only survived an average of 29 days.
LIFE CYCLE
If such short lifetimes are typical, it would boost the true impact of materials and manufacturing above the researchers’ estimates, Johnson said. He and his colleagues assumed the scooters operated for at least six months.
And “even when we’re generous, it still looks pretty bad,” said Matt Chester, an energy analyst at Chester Energy and Policy who published a back-of-the-envelope life cycle assessment of e-scooters that reached broadly similar conclusions.
The other big environmental cost associated with scooters comes from the laborious process of collecting, charging and redeploying them each night.
Lime and Bird farm out the job to independent contractors who get paid by the scooter. Sometimes, you see cars piled high with spent two-wheelers. But often, Johnson said, competition forces people to travel farther to round up fewer vehicles, which adds to their environmental impact.
“I see people driving around picking up these scooters all the time,” Chester said. “Maybe it’s still a net positive, but it can’t be as good as they say.”
Based on their estimates for Raleigh, Johnson and his colleagues found that the nightly collection and redistribution of scooters accounted for 43 per cent of their overall global warming impact. Electricity for charging the scooters represented just 5 per cent, and shipping even less.
The researchers considered a wide range of factors that could make the overall footprint of scooters bigger or smaller. But they found that 65 per cent of the time, scooters were worse than what they replaced.
In their baseline case, they found that riding one mile on a scooter produced the equivalent of 202 grams of carbon dioxide. That’s much less than a car (which emits 414 g of CO2 per mile), but more than riding a moped (119 g), taking a bus (82 g), biking (8 g) or walking(0 g).
Without scooters, users would have opted for a mixture of these options. When Johnson and his students surveyed 61 scooter users in Raleigh, half of them said they’d have walked or biked, and 11 per cent would have taken a bus. A third of them would have gone by car(either their own or using a ride-hailing service). The other 7 per cent would not have made the trip at all. (These responses square with the results of a larger poll conducted by the city of Portland,Oregon, in 2018.)
— Reuters
Oman Observer is now on the WhatsApp channel. Click here
