Driverless taxis, driverless buses, and the future urban mobility mix
Antonio Loro is an urban planner who focuses on the planning implications of emerging road vehicle automation technologies. He has conducted research with TransLink and Metrolinx on the potential impacts of automated vehicles, and is currently with the Ministry of Transportation of Ontario. This article was written by Antonio Loro in his personal capacity. The views expressed in this article are the author's own and do not necessarily represent the views of the previously mentioned organizations.
As efforts to develop automated vehicles continue to speed forward, researchers have begun to explore how driverless taxis in particular could play a prominent role in the future mix of urban transportation options. Some of these early findings raise the provocative argument that driverless taxis (or self-driving or fully-automated taxis, if you prefer) could hugely reduce or even eliminate the need for buses and trains. However, careful interpretation of this research reveals that vehicles with high passenger capacities (bus and rail transit, in other words) could be superseded by lower-capacity vehicles only where there is plenty of road space to spare. Where road lanes are in shorter supply, buses and trains – which could themselves get a huge productivity boost from automation – will continue to be indispensable for moving large volumes of passengers. In such cases, driverless taxis, especially share taxis, will be ideally suited to complement higher-capacity transit, generally by focusing on areas with a surplus of road space. And in the near-term, even before such advanced automation is perfected, automated buses could start improving mobility for large numbers of urban travelers.
Researchers have begun to explore future scenarios where vehicle automation technologies have advanced to a level that enables taxis to drive without human intervention through the full network of urban roads. Recently, the ITF (International Transport Forum), a think tank within the OECD, modeled a number of scenarios to examine how these driverless taxis, once they are commonplace, could serve urban travelers on a typical weekday in Lisbon. Among the outputs of their model, one is particularly attention-grabbing: even in a scenario where 8% of trips go by foot or bike, none go by transit, and the remaining 92% go by driverless taxis that serve single passengers, ITF researchers say that the number of taxis needed would be less than a quarter of the number of cars currently in use in the Portuguese capital. Such a reduction in the size of the overall fleet of cars in the city would greatly diminish parking demand. Unsurprisingly, though, in order to serve so many trips, the fleet of taxis would be used very intensively, and the total vehicle kilometres traveled (VKT) in the city would more than double.