UC Davis Institute of Transportation Studies

Total cost of ownership (TCO) studies are generally used as a tool to understand how and when plug-in electric vehicle (PEV) technology will reach cost parity with conventional fuel vehicles. Post cost-parity, the PEV market should be able to sustain without government intervention. The researchers present here a detailed analysis of vehicle manufacturing costs and market-level TCO accounting for technology uncertainties, behavioral heterogeneity, and key decision parameters of automakers. Using the estimates of the vehicle manufacturing costs, they estimate the cost of electrification of California’s LDV fleet to achieve the state’s net-zero emission goal by 2045. The results suggest that PEVs may not be cost competitive even in 2030 without stronger policy support and automakers initiative. Moreover, TCO is not a single number, and the cost of electrification will vary across the population based on the cost of vehicles available in the market, their charging capabilities at home and public, and energy costs. The TCO estimates and the cost of fleet electrification analysis not only has important implications for policymakers but can also offer a foundation for understanding the effect of market dynamics on the cost-competitiveness of the PEV technology.

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There is a need to optimally allocate curb space-one of the scarcest resources in urban areas-to the different and growing needs of passenger and freight transport. Although there are plenty of linear miles of curbside space in every city, the growing adoption of ride-hailing services and the rise of e-commerce with its residential deliveries, and the increased number of micro-mobility services, have increased pressure on the already saturated transportation system. Traditional curbside planning strategies have relied on land-use based demand estimates to allocate access priority to the curb (e.g., pedestrian and transit for residential areas, commercial vehicles for commercial and industrial zones). In some locales, new guidelines provide ideas on flexible curbside management, but lack the systems to gather and analyze the data, and optimally and dynamically allocate the space to the different users and needs. This study conducted a comprehensive literature review on several topics related to curb space management, discussing various users (e.g., pedestrians, bicycles, transit, taxis, and commercial freight vehicles), summarizing different experiences, and focusing the discussion on Complete Street strategies. Moreover, the authors reviewed the academic literature on curbside and parking data collection, and simulation and optimization techniques. Considering a case study around the downtown area in San Francisco, the authors evaluated the performance of the system with respect to a number of parking behavior scenarios. In doing so, the authors developed a parking simulation in SUMO following a set of parking behaviors (e.g., parking search, parking with off-street parking information availability, double-parking). These scenarios were tested in three different (land use-based) sub-study areas representing residential, commercial and mixed-use.

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This report highlights key themes from a series of ten interviews with U.S. cities with micromobility programs in their jurisdictions (Atlanta, GA; Austin, TX; Chicago, IL; District of Columbia; Denver, CO; Los Angeles, CA; Oakland, CA; Portland, OR; San Diego, CA; Seattle, WA). The research aims to shed light on both the regulatory process and identify best practices for dockless bike and scooter sharing policy. The following themes emerged among the cities interviewed: a) Data-sharing requirements for scooters and dockless bikes are critical for evaluation and monitoring for compliance with policies like equitable distributional requirements; b) Clear parking regulations for dockless bikes and scooters must balance flexibility and preserve community space ; c) Fines are effective tools to reduce bad behavior from users of micromobility devices, e.g., incorrect parking, or reckless riding behavior; and d) Clear classifications of micromobility devices will allow cities to target guidance and update regulations over time to improve clarity and outcomes. Finally, the paper concludes that more research is needed to refine these findings in this new and rapidly growing micromobility marketplace.

The Mechanistic-Empirical Pavement Design Guide (MEPDG) is a comprehensive tool developed in 2002 by the American Association of State Highway and Transportation Officials (AASHTO) to analyze and design both flexible and rigid pavements. The models in the MEPDG are implemented in software called Pavement ME, a program calibrated using Long-Term Pavement Performance (LTPP) sections from throughout the United States, including some from California. The MEPDG recommends that nationally calibrated models be validated using local data, and if necessary, recalibrated, which makes sense when considering the climate and materials differences between California and the rest of the nation. The first step in recalibrating Pavement ME is to perform a sensitivity analysis to identify which variables are most important and to look for results that do not match expected performance. The factorial for the sensitivity analysis was designed to identify sensitivity and is not the factorial to be used for the development of design tools. This report presents the results of a sensitivity analysis showing the effects of design input variables controlled by the designer, and those not known to the designer. The sensitivity analysis shows that the overall jointed plain concrete pavements (JPCP) performance prediction by Pavement ME is reasonable. The distresses predicted by Pavement ME did not show any unexpected trends for any of the variables considered in this sensitivity analysis. Over the course of this study, no major issues were identified in running Pavement ME. The next steps are to complete the calibration using California pavement management system data and then to develop the design tool with the calibrated Pavement ME coefficients.

This report presents evidence that gasoline prices have a larger effect on demand for battery electric vehicles (BEVs) than do electricity prices in California. A spatially-disaggregated panel dataset of monthly BEV registration records was matched to detailed records of gasoline and electricity prices in California from 2014-2017, and the matched data was used to estimate the effect of energy prices on BEV demand. Two distinct empirical approaches (panel fixed-effects and a utility-border discontinuity) yield remarkably similar results: a given change in gasoline prices has roughly four times the effect on BEV demand as a similar percentage change in electricity prices.

This project investigated changes in travel behavior by owners of partially automated electric vehicles. Partial automation can control vehicle speed and steering using sensors that monitor the external environment. The researchers used review results from survey responses including 940 users of partial automation, of which 628 who have Tesla Autopilot and 312 with systems from other automakers. Autopilot users report using automation more than users of other partial automation systems. Autopilot has the largest impact on travel, notably 36% of Autopilot users reporting more longdistance travel. Respondents who are younger, have a lower household income, use automation in a greater variety of traffic, roads, and weather conditions, and those who have pro-technology attitudes and outdoor lifestyles are more likely to report doing more long-distance travel. The project used propensity score matching to investigate whether automation leads to any increase in respondents’ annual vehicle miles travelled. For simplicity, the researchers focused only on the impact of Tesla Autopilot and found that automation results in an average of 4,884 more miles being driven per year.

The purpose of this report is to provide a research-driven analysis of options that can put California on a pathway to achieve carbon-neutral transportation by 2045. The report comprises thirteen sections. Section 1 provides an overview of the major components of transportation systems and how those components interact. Section 2 discusses the impacts the COVID-19 pandemic has had on transportation. Section 3 discusses California’s current transportation-policy landscape. These three sections were previously published as a synthesis report. Section 4 analyzes the different carbon scenarios, focusing on “business as usual” (BAU) and Low Carbon (LC1). Section 5 provides an overview of key policy mechanisms to utilize in decarbonizing transportation. Section 6 is an analysis of the light-duty vehicle sector, section 7 is the medium- and heavy-duty vehicle sectors, section 8 is reducing and electrifying vehicle miles traveled, and section 9 is an analysis of transportation fuels and their lifecycle. The following sections are an analysis of external costs and benefits: section 10 analyzes the health impacts of decarbonizing transportation, section 11 analyzes equity and environmental justice, and section 12 analyzes workforce and labor impacts. Finally, future research needs are provided in section 13. The study overall finds that cost-effective pathways to carbon-neutral transportation in California exist, but that they will require significant acceleration in a wide variety of policies.

For the market introduction of electric vehicles to be successful, first-time adopters need to make continual purchases of the vehicles. Discontinuance, the act of abandoning a new technology after once being an adopter, has implications for market growth and could prevent electric vehicles from ever reaching 100% market share. Using results from five surveys of electric vehicle owners, the researchers examine discontinuance among battery electric and plug-in hybrid electric vehicle adopters. In this sample, discontinuance occurs at a rate of 21% for plug-in hybrid adopters and 19% for battery electric vehicle adopters. They show that discontinuance is related to dissatisfaction with convenience of charging, owning household vehicles with lower efficiencies, being a later adopter of PEVs, not having Level 2 (220V) charging from home, and not being male. Despite consumers overcoming initial barriers of PEVs, it appears some barriers, notably their refueling style, resurface during ownership and eventually become a barrier to continuing with PEV ownership.

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Zero-emission vehicles are seen as key technologies for reducing freight- related air pollution and greenhouse gas emissions. California’s 2016 Sustainable Freight Action Plan established a target of 100,000 zero-emission freight vehicles utilizing renewable fuels by 2030. Hydrogen fuel cell vehicles are a promising zero-emission technology, especially for applications where batteries might be difficult to implement, such as heavy-duty trucks, rail, shipping and aviation. However, California’s current hydrogen infrastructure is sparse, with about 25 stations, primarily sited to serve fuel cell passenger vehicles and buses. New infrastructure strategies will be critical for implementing hydrogen freight applications. The researchers analyzed hydrogen infrastructure requirements, focusing on hydrogen fuel cells in freight applications, using a California-specific EXCEL-based scenario model developed under the Sustainable Transportation Energy Pathways program (STEPS) at the Institute of Transportation Studies at UC Davis (Miller et al, 2017). Hydrogen vehicle adoption and demand was estimated for trucks, rail, shipping, and aviation, for a range of scenarios out to 2050.

The public mandate to engage the public in transportation planning processes is in the process of becoming more rigorous and democratic. Transportation agencies are recognizing the limitations of past modes of engagement and seek to connect more dynamically with the public, particularly with historically marginalized communities. Doing this work well is a topic of interest to a growing number of transportation professionals. This study identified four successful engagement processes with historically marginalized communities in California by surveying transportation professionals. Stakeholders at each site were interviewed and public documents from the processes were reviewed to identify common themes for positive public inclusion. Interviewees included community leaders, transportation staff, and consultants. Interviews were coded and analysis was conducted using a mobility justice and critical race studies framework. Ten key themes of successful community engagement with historically marginalized communities were identified. These themes are: (1) trust is crucial; (2) treat community-based organizations as equal partners; (3) pay community partners fairly; (3) let community-based organizations decide what good community engagement is; (5) translate technical jargon; (6) engage in community concerns beyond the scope of the project; (7) address major community concerns such as displacement, policing, and youth development; (8) know local histories of transportation injustice; (9) include the community in the final reporting process; and (10) follow-up on planning with implementation in a timely manner.