Can Shared Mobility Fix Everything? Just Maybe, it Can

Posted by: Tony Dutzik on

Tags: transportation

Imagine a city with no traffic congestion, no cars parked at the curb, and plenty of space to walk, bike or mingle on the sidewalk. Imagine efficient, door-to-door mobility, accessible to everyone, even in the dead of night. Imagine more money in your pocket and a cleaner environment for your children.

Sound like an urban transportation utopia?

A May study by researchers affiliated with the International Transport Forum (ITF) suggests that all of this might be possible in real cities, using technology available today, through the wonders of shared mobility … but also that getting to urban transportation nirvana will not be easy.

The new ITF study is the second in a series of modeling exercises looking at the potential effects of new mobility services in a single city: Lisbon, Portugal. Researchers posed an elaborate what-if: what if all private vehicle and bus traffic in Lisbon were to be replaced with on-demand shared taxis (think UberPool or LyftLine) and 8- to 16-passenger shared “taxi-buses”?

The results are eye-popping. Assuming that people continue to walk, bike, or use the city’s metro system in roughly the numbers they do now, the shared vehicle system would:

  • Eliminate congestion.
  • Cut the number of vehicles on the road by 97% and parking utilization by 95%.
  • Cut vehicle-miles traveled by 23% and greenhouse gas pollution by 34%.
  • Dramatically expand access to jobs for residents throughout the city.

The system delivers these benefits while maintaining high quality service – 90 percent of users or more would be matched with a shared-taxi ride in 6 minutes or less, with half waiting less than 3 minutes, even in the late night and early morning hours. And it can do so at dramatically lower cost than current bus and taxi service, and with lower lifetime costs than vehicle ownership for most consumers.

The ITF report also explores important questions about the interactions between shared mobility and other rapidly advancing technologies:

  • Autonomous vehicles: The shared mobility system evaluated in the study assumes that the shared taxis and taxi-buses would be driven by human drivers. Autonomous vehicles are not a prerequisite for a comprehensive system of shared mobility.
  • Electric vehicles: The study is bullish on the potential to integrate electric vehicles into a shared mobility system, finding that “the use of electric vehicles is compatible with the job they have to perform as shared taxis” and that the requirements for new charging stations – and the investment that would be required to build them – are relatively low.

So far, so good. But a few caveats are in order. First, most American cities are very different from Lisbon. In its recent recommendations (PDF) on autonomous vehicles, the National Association of City Transportation Officials (NACTO) recommended replicating the Lisbon modeling work in an American city. Given the transformative potential seen in the Lisbon exercises, that would seem to be a high priority for U.S. transportation research.

Second, even the best modeling exercises can’t replicate real life, and so the ultimate results of such a switch might not be quite so rosy. Finally, the involvement of corporate partners in this particular study should cause one to look at the results with a critical eye.

The biggest caveat, however, is that the Lisbon analysis puts forward a vision of a fully realized reality – one in which all private cars have been raptured out of our cities and replaced instantaneously with shared vehicles. In reality, as the authors note, we will need to navigate a transition from our current urban transportation system to a new system based on shared rides and vehicles.

That transition is likely to be challenging, to say the least.

According to the ITF analysis, the real societal benefits of the shared mobility system don’t begin to kick in until more than 40 percent of all private car trips in the city have been eliminated (though benefits accrue rapidly once 60 percent or more of private car trips are replaced). That suggests a few things:

1)      Policy-makers would need to use carrots and sticks in order to spur this transition along. It will not just happen. Discounted access to the shared mobility system, restrictions or fees on private vehicle travel and other measures would likely be needed for cities to get this system up and running.

2)      Inherently, those “carrots” would require the investment of societal resources that might currently be spent on other things, while the “sticks” would impose costs on real constituencies. If you think transit agencies subsidizing Uber rides, or cities taking a few parking spaces for carsharing are controversial, you ain’t seen nothing yet. Political courage and a sense of vision and commitment would be essential to making this work.

3)      During the transition period – which may last for several years or more – nothing will seem to get much better. Vehicle travel and congestion will not fall, while parking demand might drop just a bit. Maintaining costly and/or politically difficult commitments during this transitional period of minimal benefits would require patience.

4)      Needless to say, the system’s success requires a heavy cultural lift: convincing Americans to forego private vehicle ownership. Is that culture change possible? The following tweet, which tore up Twitter earlier this month, suggests that it might be, though it is still likely to be difficult:


The transition to a fully shared system of mobility is not the only possible pathway to a sustainable, efficient transportation system. Our May report, A New Way Forward, describes a variety of pathways cities might use to get there. Still, the ITF study gives us a detailed picture of the heaven that might be if we were to embrace a new transportation paradigm less dependent on personal car ownership. Urban leaders, policy-makers and advocates should take a good, hard look at the ITF study, and imagine how shared mobility might be integrated into a locally generated vision of a new transportation future.