Air Pollution, Greenhouse Gas, and Traffic Externality Benefits and Costs of Shifting Private Vehicle Travel to Ridesourcing Services

Abstract

On-demand ridesourcing services from transportation network companies (TNCs), such as Uber and Lyft, have reshaped urban travel and changed externality costs from vehicle emissions, congestion, crashes, and noise. To quantify these changes, we simulate replacing private vehicle travel with TNCs in six U.S. cities. On average, we find a 50–60% decline in air pollutant emission externalities from NOx, PM2.5, and VOCs due to avoided “cold starts” and relatively newer, lower-emitting TNC vehicles. However, increased vehicle travel from deadheading creates a ∼20% increase in fuel consumption and associated greenhouse gas emissions and a ∼60% increase in external costs from congestion, crashes, and noise. Overall, shifting private travel to TNCs increases external costs by 30–35% (adding 32–37 ¢ of external costs per trip, on average). This change in externalities increases threefold when TNCs displace transit or active transport, drops by 16–17% when TNC vehicles are zero-emission electric, and potentially results in reduced externalities when TNC rides are pooled.

Shared mobility and vehicle lifetimes – implications for the carbon footprint

“…Such services could replace individual car ownership, but they may also increase driving distances because of empty travel. This risk is evident for current taxis and ride sourcing services [15][16][17] as well as in simulations of future transport systems using shared autonomous vehicles 11,14 . In the next section, we explore how empty travel could impact the carbon footprint when simultaneously considering the possible influence that increased driving intensity might have on the lifetime of vehicles.…”

“…Simulation studies of shared autonomous vehicles have found that empty travel could increase the total vehicle travel distance by 10% to 100% in urban areas compared to the intended travel distance (i.e., the distance traveled by the car to transport a passenger or a group of passenger from one point to another) 11,14 . Empirical studies show a level of around 60% for taxi rides 15 and 40% for ridesourcing services 16,17 on top of the intended travel distance.…”

Electrifying New York City Ride-Hailing fleets: An examination of the need for public fast charging

“…Ride-hailing electrification has gained momentum in recent years as regulators have set aggressive targets for fleet electrification (California Air Resources Board, 2018). Successful fleet electrification would help reduce the negative externalities associated with ride-hailing, such as increased emissions (Anair et al, 2020;Ward et al, 2021). Major ride-hailing companies, most notably Uber and Lyft, have responded by setting aggressive goals of their own; both companies have pledged to fully electrify their fleets by 2030 (Khosrowshahi, 2020;Lyft, 2020).…”

Understanding the Recovery of On-Demand Mobility Services in the COVID-19 Era

“…Third, the pandemic can alter the competition and substitution among different travel modes. Without proper investigation and intervention, such competition may lead to unwanted results such as additional congestion and pollution (Ward et al 2021;Qian et al 2020a). Finally, we need a framework to understand how the transportation systems recover during disruptions such as COVID-19 which do not physically impact the infrastructure but lead to significant changes in the ridership.…”