My colleague Dewey Szemenyei and I have just published our latest paper, The Impact of the Motorized Scooter Rental Industry on the City of San Diego’s Climate Action Plan Goals. A copy is available from the panel to the right.

We had published a similar study in 2019 the conclusion of which was that the rental industry is not decreasing carbon emissions but instead is increasing them. We have updated our analysis with recent data and expanded it to examine the GHGs of each current vendor. We hoped to find that the net greenhouse gas, (GHG), emissions of the industry, i.e. the emissions it creates minus the GHGs saved, was negative, as this would indicate that the motorized scooter rental industry was helping the City achieve its CAP goal.

However, the result is that, as it was four years ago, the motorized scooter rental industry is a net polluter. As such then it is undermining the City of San Diego’s goal of cutting emissions significantly by 2035. 

“Our calculations indicate that, after allowing for the emissions it replaces, the motorized scooter rental industry in San Diego, is currently adding over three million pounds, (0.0158 million metric tons), of greenhouse gas equivalents, (GHGs), to the city’s carbon footprint annually, more than would be created by a 30 acre forest fire 3 or that results from the gasoline burned by 200 cars in a year.

They also indicate that for all operators the net emissions are positive, not negative, i.e. all the operators are increasing carbon emissions in the city, though some do so to a greater degree than others.”

We explain the reasons for this:

“The principal causes relate to both the rental companies and their customers:

Companies:

Durability: Motorized rental scooters have a short lifespan compared to a car and many scooters must be manufactured to match the transportation distance a car provides over its life.

Operations: Unlike both privately owned cars and privately owned motorized scooters, companies that provide motorized scooters for rent use fleets of GHG-emitting vans to relocate their rented devices.

Renters:

Joy-riding: Unlike cars, motorized rental scooters are often driven for “fun” or “thrills” rather than for utilitarian transportation. This does not replace car journeys and rather than decreasing carbon emissions it increases them as it increases the emissions due to manufacturing and operations.

Replacement of No/Low Carbon Emitting Alternatives: Often motorized scooters are used to replace zero or low carbon emission alternatives such as walking and public transit. Renting a motorized scooter to replace walking does not reduce carbon emissions.”

We examine what the effect of the City switching to the proposed RFP contract system selecting four operators managing a total of 8,000 devices and conclude that all other things equal:

“…our calculations indicate that, as shown in Table 2, the industry will still be acting counter to the City’s CAP goals…”

We also compare renting a motorized scooter with renting one and conclude that privately owned scooters emit much less GHGs and could help reduce emissions.

Our analysis leads to some suggestions:

• To be most environmentally friendly e-scooters should be constructed to optimize service life and GHG of manufacture to achieve the lowest ratio of manufacturing GHG to service life.
• Install solar powered charging stations and replace gasoline powered vans with electric vans or e-cargo bikes to service their fleets.
• Motorized scooter enthusiasts who rent could be encouraged to own though motorized scooters are prohibited from many roads in California and a more versatile device may be a preferable alternative for private ownership.
• Joyriding should be discouraged.