As electric vehicles gain traction researchers discover e-taxi tipping point

There are nearly two-dozen major cities worldwide investing in electric taxis, with many more to follow. But numerous studies have shown that these e-taxis operate at a disadvantage as compared to internal combustion engine (ICE) powered taxis because of such adoption challenges as charging times and queue delay, which cut into the drivers’ need to earn fares. Charging time even for Class III chargers can take 30 minutes, and while there are thousands of charging stations in Chinese cities like Shenzhen, in the U.S. such facilities are sparse.

What will it take to get taxi fleets to make the switch? Joseph Chow, a professor in the Department of Civil and Urban Engineering and deputy director of NYU Tandon’s C2SMART University Transportation Center, and Jaeyoung Jung, a sustainability analyst at the Ford Motor Company, have found the answer by executing an innovative set of simulations.

Using data from New York City’s Department of Transportation, the researchers confirmed earlier predictions that e-taxis cannot easily compete with ICE vehicles, but that there are ways to mitigate this economic imbalance favoring gasoline.

The study, Effects of Charging Infrastructure and Non-Electric Taxi Competition on Electric Taxi Adoption Incentives in New York City, which was published in Transportation Research Record, the journal of the Transportation Research Board, is the first to use statistical modeling to identify the inflection points for adoption in factors like charging station availability and percentage of e-taxis in operation versus ICE taxis.

Using an established taxi simulation model to evaluate the New York City Taxi and Limousine Commission’s own charging station design proposal, the team was able to quantify the subsidy requirements of operating an e-taxi in a setting like NYC and analyze the contribution that factors like charging station availability and charging time have on the incentives needed to encourage fleet owners to adopt e-taxis. The researchers also identified the number of charging stations and locations that would make the infrastructure portion of the subsidy negligible.

Among other key takeaways, the researchers found that incentives designed to nudge fleets to adopt e-taxis need to be applied to entire fleets, rather than on a vehicle-by-vehicle basis, because if only part of a fleet is subsidized, the subsidy may not cover the additional cost gap that arises from the competitive advantage gained by ICE or gas/electric vehicles operating in the same market.

Chow said the other critical factor is perhaps the most obvious one: if cities don’t build it, the e-fleets won’t come. “The results show why individual incentives won't work unless sufficient charging infrastructure is available.”