Myth 1: Rented Scooters Decrease Carbon Emissions
- People assume that if they drive a rented electric scooter they are reducing carbon emissions. This is false; they are increasing carbon emissions because:
- Rented scooters don't last long, millions must be manufactured and that pumps carbon into the atmosphere.
- Rented scooters are dockless and get scattered around the city and the rental companies use fleets of carbon spewing trucks to move them around.
- Most users don't replace car trips. Instead they replace walking. That doesn't save carbon. Nor does joy-riding for fun. In fact, using rented scooters for fun increases carbon emissions because of the other factors: more scooters need to be made and fleets of carbon spewing vans move them around. The better option for fun is WALKING.
The Illusion That Renting A Scooter Reduces Carbon Emissions
Most of the shared motorized scooter companies claim that using a rented scooter is "environmentally friendly". They told governments that letting them operate in their cities will help them meet the carbon emission reduction goals in their Climate Action Plans. In San Diego they claimed each mile traveled by motorized scooter was equivalent to a mile travelled by a gasoline powered car, i.e. that every journey undertaken by scooter replaced a journey that would otherwise have been taken by car. As the scooters are electrically powered, this seemed to make sense as driving a scooter emits no carbon. Any carbon created in generating electricity to power the scooter could be dismissed as insignificant. So, superficially, electric motorized scooters seemed "green".
The Reality: The Scooter Rental Industry Increases Carbon Emissions
However, the truth is otherwise. The scooter rental industry has taken a product that, if owned privately, cared for and used conscientiously to replace car travel, could help reduce carbon emissions and has created a system that, in its totality, increases carbon emissions.
This is explained in detail in the analysis by Szemenyei and Freeman, "The Impact of the Motorized Scooter Rental Industry on the Carbon Footprint of San Diego", published online in February 2019, and as indicated by numerous subsequent studies only some of which are referred to on the right. The reasons are obvious once one thinks about them:
LOTS OF CARBON IS EMITTED WHEN LOTS OF SCOOTERS ARE MADE. Because scooters are fragile and renters abuse them, they don't last long: early reports estimated their lifespan at less than a month. Even though more modern scooters last longer, huge numbers of scooters still have to be manufactured to create transportation mileage equivalent to that of a car. Just think for a moment of how many miles the average car travels over its lifetime... was your answer 200,000 to 300,000 miles?. Compare that with a rental scooter which today the rental companies claim can last one to two years. That's questionable given the way scooters are treated, the weather conditions they are exposed to etc. but let's go with that two year lifespan for the moment and assume a scooter is driven twice a day and each trip covers 1.5 miles. So, over its two year life the rental scooter would travel, 2,190 miles, (1.5miles x 2trips x 365days x 2years). So to obtain mileage equivalent to a car roughly 100 scooters would need to be manufactured and that's assuming the claims of the companies are accurate. Yet, for each scooter manufactured, carbon is emitted, and, as we elaborate below, studies and surveys have repeatedly confirmed for years now that the the most frequent mode of transport rental scooters replace is walking.
CARBON IS EMITTED WHEN RENTED SCOOTERS ARE STAGED, COLLECTED, RELOCATED, EVEN WHEN THEY HAVE REPLACEABLE BATTERIES.
The "shared" nature of renting and the "you can leave them anywhere" proposition means that users leave rented scooters in locations that are less than ideal for the rental companies and therefore they reposition them. They must also be collected to be maintained and staged for renting at the start of each day. To do all this moving of scooters, the companies have employed gasoline and diesel powered vans and trucks, all of which emit carbon. That's not true of all the companies; in San Diego Lyft employs a guy using a tricycle cart to move them around downtown, (in addition to gas guzzling vans). but it's true for most of the rest. Even with Lime's new model scooters that have replaceable batteries, carbon spewing trucks are used.
SCOOTERS ARE USED FOR FUN, BUT THAT DOESN'T REPLACE CAR TRIPS. Users often do not use scooters for transportation but take them for drives simply "for fun". Each mile travelled for fun does not replace a mile travelled by car and so does nothing to reduce carbon emissions. In fact because of the two points above, using them for fun increases carbon emissions - driving a scooter for fun reduces its remaining lifespan and leads to gas guzzling trucks and vans having to move it around.
Travel by an electric-powered platform on wheels creates the illusion that one is helping fight climate change largely because the renters don't think about the other points. This fun factor is affected by things like the number of tourists in a city and that can be affected by climate. San Diego's climate is ideal and tourists flock to the city. Indeed, SanDiego.org estimates that "San Diego hosts nearly 35.1 million visitors each year, and is a top U.S. travel destination". SanDiego.org does not estimate the number who travel with a bike helmet, but if it's not zero it's likely to be a tiny fraction of that number.
YOU DON'T REPLACE CAR TRIPS WHEN YOU DON'T REPLACE CAR TRIPS. People renting scooters often do not do so to replace using a car. Instead they often replace walking, cycling and using mass transit. Every mile travelled by scooter that replaces walking, cycling and mass transit does nothing to reduce carbon emissions. In fact, given the other factors, it increases them - renting a scooter reduces its life span requiring another to be made eventually and, in the meantime, for people to drive around in vans and trucks to move it around. Walking is also a widely recognized healthy option, so replacing walking with scooter driving could have adverse health consequences, (apart from the cranial injuries resulting from falls).
Overall, the estimate in our paper was that, in San Diego, six miles travelled by scooter would replace one mile travelled by car.
Even the following video, which comes to an ambivalent conclusion misses the systemic effect of the "dockless" ride share industry: fleets of carbon-emitting vans driven around a city to create the illusion of carbon-free travel.
"Are dockless scooters environmentally friendly? (Bird and Lime)". Jan 18, 2019
What Do Renters Substitute Scooters For?
Whether rented scooters decrease carbon emissions depends on what renters substitute them for.
Is it, as Bird and Lime told the City Council, that every mile of scooter use replaces a mile travelled by car? On that basis one might expect an impact on carbon emissions, especially if the rental industry moved scooters around using non-carbon emitting vehicles.
On the other hand, if every mile of scooter use always replaced walking then, with all the other sources of carbon associated with the industry, (e.g. manufacture and relocation), the rental industry will be increasing carbon emissions.
An academic study by Wang et al, (2022), cited and linked to on the right of this page, reviewed the literature on e-scooter use. Some interesting quotes:
"In nearly every study we reviewed, shared e-scooter users report walking as the most common travel mode substituted, ranging between 30 and 60% of trips ... Shared e-scooters are more likely to replace walking trips than other modes of transport."
"Shared e-scooters are less likely to be used for commuting compared to shared bikes."
"Many e-scooter riders feel safe on the sidewalk. However, riding on the sidewalk should be discouraged or prohibited by local authorities as e-scooters travel much faster than people who travel on foot, potentially causing traffic safety risks to pedestrians and increasing the likelihood of collisions (Fitt & Curl, 2019; James et al., 2019). Fitt and Curl (2019) reported that over 90% of e-scooter users have ridden on the sidewalk. Amongst them, most were aware that the footpath was not a suitable environment for riding e-scooters."
"In 2019, the San Francisco Municipal Transportation Agency (SFMTA) administered surveys to a sample of active users of three shared micromobility service companies (i.e. Scoot, Skip, and JUMP). The results show that nearly 30% of e-scooter trips induced new transit trips, where e-scooters had been used as a first/last-mile connection. Barnes (2019) concluded that both bikesharing and shared e-scooters could connect users to public transit without cars, promoting public transit ridership. Moreover, survey results suggest that shared e-scooters are more likely to be used for first/last mile connections than dockless e-bikes. The two shared micromobility services are likely to fill different travel needs. The SFMTA report provides empirical evidence that shared e-scooters are complementary to the public transit system."
"The substitution rate of riding e-scooters for auto trips is within 25-40% in most cases."
So, if as is the case in San Diego, rental scooters are not well-integrated into the transit system, then just leaving them in the tourist areas of the city for people to rent in the Summer when they don't replace car trips and most frequently replace walking, is bound to INCREASE carbon emissions.
A Partial List of Academic Studies of the Scooter Rental Industry
- Reck, Daniel J., Martin, Henry and Axhausen, Kay W., Mode choice, substitution patterns and environmental impacts of shared and personal micro-mobility, Transportation Research Part D: Transport and Environment, Volume 102, 2022, https://doi.org/10.1016/j.trd.2021.103134.
- Wang, Kailai, Qian, Xiaodong, Fitch, Dillon Taylor, Lee, Yongsung, Malik, Jai & Circella, Giovanni (2022): What travel modes do shared e-scooters displace? A review of recent research findings, Transport Reviews, DOI: 10.1080/01441647.2021.2015639.
- Zoi Christoforou, Anne de Bortoli, Christos Gioldasis, Regine Seidowsky, Who is using e-scooters and how? Evidence from Paris, Transportation Research Part D: Transport and Environment, Volume 92, 2021, https://doi.org/10.1016/j.trd.2021.102708.
In 2018 Bird and Lime made presentations to the City. Below is some of what they said.