preprint journal article

A Choice Experiment Survey of Drayage Fleet Operator Preferences for Zero-Emission Trucks

Abstract

Many U.S. states are supporting the transition of the heavy-duty vehicle (HDV) sector to zero-emission vehicles (ZEVs), with California leading the way through its policy and regulatory initiatives. Within various HDV fleet segments, California’s drayage fleets face stringent targets, requiring all vehicles newly registered in the Truck Regulation Upload, Compliance, and Reporting System to be ZEVs starting January 2024, and all drayage trucks in operation to be zero-emission by 2035. Understanding fleet operator behavior and perspectives is crucial for achieving these goals; however, it remains a critical knowledge gap. This study investigates the preferences and influencing factors for ZEVs among drayage fleet operators in California. A stated preference choice experiment survey was conducted, developed based on previous qualitative studies and literature reviews. With participation from 71 fleets of various sizes and alternative fuel adoption status, there were 648 choice observations in a dual response design collected, consisting of a forced choice between ZEVs and a free choice between ZEVs and status quo alternatives. Multinomial logit model analyses revealed driving range and purchase costs as significant factors for ZEV adoption, with charging facility construction costs also critical in hypothetical choices between ZEVs and status quo alternatives. Fleet or organization size also influenced ZEV choices, with large fleets more sensitive to operating costs and small organizations more sensitive to off-site stations. These findings enhance understanding in this area and provide valuable insights for policymakers dedicated to facilitating the transition of the HDV sector to zero-emission.

preprint journal article

Charging Infrastructure Decisions by Heavy-duty Vehicle Fleet Operators: An Exploratory Analysis

Abstract

Insufficient charging/fueling infrastructure poses a major challenge to achieving U.S. policy goals for transitioning the heavy-duty vehicle (HDV) sector to zero-emission vehicles. Addressing the infrastructure needs of HDV fleet operators, who are key demand-side stakeholders, is crucial for developing effective solutions and strategies. This study investigates these needs through a fleet survey of California’s drayage sector, focusing on battery electric trucks. Key aspects examined include preferences for charging locations, access types, charging duration, time-of-day for charging, and innovative solutions like Truck-as-a-Service. Analyzing responses from 53 companies with varying fleet sizes, annual revenues, and operational characteristics, the study employed a comprehensive exploratory approach, utilizing descriptive analysis, thematic analysis, and hypothesis testing. Findings reveal that while most fleets preferred on-site charging, about a quarter, primarily smaller fleets with five or fewer trucks, preferred both on-site and off-site options. Private access was often favored for on-site facilities, though some respondents recognized the benefits of shared access for expanding operational coverage. The study also identified a need for faster charging solutions at both off-site and on-site locations, particularly for long-haul or mixed operations. Time-of-day preferences varied widely, driven by the need for efficient operations. Furthermore, a small proportion of participating fleets preferred Truck-as-a-Service over traditional procurement, predominantly among smaller fleets or those with lower revenues. The comprehensive research findings contribute to a deeper understanding of charging infrastructure needs and offer practical insights for policy practitioners and industry stakeholders committed to advancing zero-emission infrastructure. ​​

preprint journal article

Small and Large Fleet Perceptions on Zero-emission Trucks and Policies

Abstract

Given that small fleets (defined as those with 20 or fewer vehicles) represent a considerable portion of the heavy-duty vehicle (HDV) sector, understanding their perspectives, along with those of large fleets, on zero-emission vehicles (ZEVs) and related policies is crucial for achieving the U.S. HDV sector’s ZEV transition goals. However, research focusing on small fleets or comparing both segments has been limited. Focusing on California’s drayage sector with stringent ZEV transition targets, this study investigates the awareness and perceptions of small and large fleet operators on ZEV technologies and policies established to promote ZEV adoption. Using a fleet survey, we obtained 71 responses from both small and large fleets. We employed a comprehensive exploratory approach, utilizing descriptive analysis, hypothesis testing, and thematic analysis. Findings reveal that both segments generally rated their ZEV knowledge as close to neutral, with about a third reporting limited awareness of the ZEV policy. Both segments highlighted various adoption barriers, including challenges with infrastructure, costs, and operational compatibility. Business strategies under the ZEV policy differed significantly: small fleets planned to delay or avoid ZEV procurement, with some considering relocation, while large fleets were more proactive, with many already having procured or preparing to procure ZEVs. Both segments voiced concerns about the disproportionate impact on small fleets. The findings enhance our understanding of equity issues in ZEV adoption across fleet segments and offer valuable insights for policymakers committed to a more equitable distribution of the impacts. ​​

policy brief

How Did Transit Service Adjustments During the Pandemic Impact Job Accessibility in the San Francisco Bay Area?

Publication Date

January 1, 2025

Author(s)

Phoebe Ho, Johanna Zmud, Joan Walker

Abstract

This study examined geographic and temporal patterns in service adjustments and evaluated their job accessibility impacts for three major San Francisco Bay Area transit agencies between 2020 and 2023: the Alameda-Contra Costa Transit District (AC Transit), the San Francisco Bay Area Rapid Transit District (BART), and the San Francisco Municipal Transportation Agency (MUNI). This retrospective analysis can help transit agencies develop equitable service strategies in the event of future disruptions.

published journal article

Demand-side challenges and research needs on the road to 100% zero-emission vehicle sales

Abstract

Most net-zero emissions targets require electrification of the entire light-duty vehicle fleet, and before that the electrification of all new vehicle sales. This paper reviews literature on demand-side issues related to achieving 100% zero-emissions vehicle sales, focusing on plug-in electric vehicles (PEVs). It discusses potential demand-side challenges to increasing PEV sales and related research gaps, including consumer factors (perceptions, knowledge, and consumer characterises), demand-focused policy (incentives), infrastructure, and energy prices. While global PEV sales have substantially increased in recent years, several challenges remain: some demographic groups are currently underrepresented among PEV buyers (e.g. renters, lower income buyers), some car drivers are resistant to PEVs, incentives are influential but have predominantly benefited higher-income new-car buyers and are being phased out, infrastructure is not sufficiently developed or equally distributed, infrastructure is not user friendly, and some households lack charging access. Some issues identified may be related to the early stage of the PEV market, though they will need to be addressed to reach higher PEV sales and PEV fleet shares. Finally, it outlines areas where more research is needed to understand and guide the PEV transition.

policy brief

Debt Burden from Automobile Loans Exacerbates Racial Inequality in California’s Communities

Abstract

Automobiles can greatly enhance access to employment and other opportunities. However, many households do not have the resources to purchase a vehicle outright and must rely on automobile loans. This increases the total cost of owning a vehicle, particularly for non-white consumers who may have to pay higher purchase prices and/or higher interest rates due to discriminatory lending practices. The effects of high household debt—of which automobile loans are one component—are magnified in lower income neighborhoods, leaving residents with fewer resources to invest in the local economy. The research team used the University of California Consumer Credit Panel, a dataset from Experian, which tracks every loan and borrower in California, to examine how and why automobile loan debt varies from place to place in the state and its consequences. They specifically tested whether total automobile debt, debt burden (the ratio of automobile debt to income), and automobile loan delinquencies in 2021 disproportionately affected non-white neighborhoods.

policy brief

Assessing the Shift to Remote and Hybrid Work in California throughout the COVID-19 Pandemic

Abstract

Beginning in 2020, many in-person activities were replaced by virtual activities as a response to the COVID-19 pandemic. This affected fundamental elements of transportation systems such as trip frequency, commute distance, origins, and destinations. For example, remote work and study were widely adopted among workers and students. Still, the ways that the pandemic affected individuals’ work arrangements across different phases of the pandemic and the extent to which full remote work and hybrid work induced by the pandemic might persist in the future are unclear. In addition, recent studies are not conclusive regarding the ways changes in work arrangements do/will impact travel patterns and trip making.

policy brief

What Matters Most to Drayage Companies When Considering a Zero-Emission Truck: Insights from Small and Large Fleet Operators

Abstract

Drayage trucks (i.e., heavy-duty trucks that move containers and bulk freight between ports and rail facilities, distribution centers, and other nearby locations) are a critical part of port operations, however, they also adversely affect air quality. In California, drayage fleets are facing strict regulatory pressure under the Advanced Clean Fleets (ACF) regulations. Starting in January 2024, all newly registered drayage trucks in the CARB Online System must be zero emission vehicles (ZEVs), so either a battery electric truck (BET) or hydrogen fuel cell electric truck (HFCET). By 2035, every drayage truck operating in California must be zero-emission.
To successfully meet this policy goal, it is important to understand the viewpoints of drayage fleet operators. However, there is limited knowledge about how fleets of various sizes, especially small fleets with 20 or fewer vehicles (which make up 70% of the sector), are responding to ZEVs and related policies. To bridge this gap, the study team surveyed both small and large drayage fleet operators at the Ports of Los Angeles and Long Beach, with 71 companies participating. As part of the survey, fleet operators were asked to choose a preferred truck under different scenarios. In the first scenario, they chose between different ZEV trucks; in the second scenario, they chose between ZEVs, diesel, or natural gas trucks, shedding light on potential reasons which fleets might delay ZEV adoption if they still prefer diesel or natural gas trucks. The team analyzed around 650 choice observations using statistical models to explore these preferences, as well as other survey items regarding their perceptions.

policy brief

On-Road Motor Vehicles No Longer Dominate Ozone Formation

Abstract

The amount of traffic on California’s roadways decreased by approximately fifty percent during the COVID-19 pandemic lockdown in March and April of 2020. Conventional wisdom led to the expectation that reduced traffic would result in reduced ozone (O3) concentrations—ozone being a main component of smog—yet ozone concentrations increased during this period. Internal combustion vehicles emit oxides of nitrogen (NOx) and volatile organic compounds (VOCs). These emissions are precursors for ozone formation, but the relationship between these precursor emissions and the final ozone concentration is complex. The ratio of NOx/VOCs determines if the ozone formation will be “NOx-limited” or “NOx-rich”. Major NOx reductions are required to reduce ozone concentrations when the atmosphere is NOx-rich. Small NOx reductions in a NOx-rich atmosphere can actually increase ozone concentrations.

To inform ongoing efforts to reduce ambient O3 concentrations, this brief highlights findings from research that collected and analyzed air pollution measurements in urban locations adjacent to major freeways in the City of Sacramento and the City of Redlands—both during and after COVID-19 stay-at-home orders. The results provide an updated estimate for how many more years of NOx control will be required before O3 benefits are realized.

published journal article

Connected Automated Vehicle Impacts in Southern California Part-I: Travel Behavior and Demand Analysis

Abstract

Connected and automated vehicle (CAV) technologies attracted extensive attention in the past decade. As CAV brings convenience to travel, people’s travel behaviors and patterns might change significantly. Existing models, however, cannot comprehensively evaluate the impacts on transportation systems. This study adopted an activity-based approach to evaluate the comprehensive CAV impacts on the transportation system in Southern California. A stated preference survey was conducted and captured people’s behavior changes associated with CAV deployment. The model prediction demonstrated that the total trip number increased by 9%, with a 13% growth in total car-like mode travel distance. Among all trip purposes, work trips contributed to 49% of total trip number growth and 75% of the increased car-like mode travel distance. The advanced CAV technology alone wouldn’t directly benefit future transportation systems and it is still critical to have appropriate policy interventions in place.