Elliot Martin

Impact of Carsharing on Household Vehicle Holdings: Results from North American Shared-Use Vehicle Survey

Carsharing has grown considerably in North America during the past decade and has flourished in metropolitan regions across the United States and Canada. The new transportation landscape offers urban residents an alternative to automobility, one without car ownership. As car-sharing has expanded, there has been a growing demand to understand its environmental effects. This paper presents the results of a North American carsharing member survey (N = 6,281). A before-and-after analytical design is established with a focus on carsharings effects on household vehicle holdings and the aggregate vehicle population. The results show that carsharing members reduce their vehicle holdings to a degree that is statistically significant. The average number of vehicles per household of the sample drops from 0.47 to 0.24. Most of this shift constitutes one-car households becoming carless. The average fuel economy of carsharing vehicles used most often by respondents is 10 mi/gal more efficient than the average vehicle shed by respondents. The median age of vehicles shed by carsharing households is 11 years, but the distribution covers a considerable range. An aggregate analysis suggests that carsharing has taken between 90,000 and 130,000 vehicles off the road. This equates to 9 to 13 vehicles (including shed autos and postponed auto purchases) taken off the road for each carsharing vehicle.

Greenhouse Gas Emission Impacts of Carsharing in North America

This paper evaluates the greenhouse gas (GHG) emission impacts that result from individuals participating in carsharing organizations within North America. The authors con ducted an online survey with members of major carsharing organizations and evaluated the change in annual household emissions (e.g., impact) of respondents that joined carsharing. The results show that a majority of households joining carsharing are increasing their emissions by gaining access to automobiles. However, individually, these increases are small. In contrast, the remaining households are decreasing their emissions by shedding vehicles and driving less. The collective emission reductions outweigh the collective emission increases, which implies that carsharing reduces GHG emissions as a whole. The results are reported in the form of an observed impact, which strictly evaluates the changes in emissions that physically occur, and a full impact, which also considers emissions that would have happened but were avoided due to carsharing. The mean observed impact is -0.58 t GHG/year per household, whereas the mean full impact is -0.84 t GHG/year per household. Both means are statistically significant. We present a sensitivity analysis to evaluate the robustness of the results and find that the overall results hold across a variety of assumptions. The average observed vehicle kilometers traveled (VKT) per year was found to decline by 27%. We conclude with an evaluation of the annual aggregate impacts of carsharing based on current knowledge of the industry membership population.

China's Hangzhou Public Bicycle: Understanding Early Adoption and Behavioral Response to Bikesharing

Over the past 20 years, China has experienced a steady decline in bicycle use. To address this trend, Chinas central and local government for urban transportation created Public Transit Priority to encourage public transport initiatives. As part of this effort, the government of the city of Hangzhou launched Hangzhou Public Bicycle in 2008. This service allows members to access a shared fleet of bicycles. As of March 2011, Hangzhou Public Bicycle operated 60,600 bicycles with 2,416 fixed stations in eight core districts. To understand factors leading to bikesharing adoption and barriers to adoption, the authors conducted an intercept survey in Hangzhou between January and March 2010. Two separate questionnaires were issued to bikesharing members and nonmembers to identify key differences and similarities between these groups. In total, 806 surveys were completed by 666 members and 140 nonmembers. The authors found that bikesharing was capturing modal share from bus transit, walking, autos, and taxis. Approximately 30% of members had incorporated bikesharing into their most common commute. Members indicated that they most frequently used a bikesharing station closest to either home (40%) or work (40%). These modal shifts suggested that bikesharing acted as both a competitor and a complement to existing public transit. Members exhibited a higher rate of auto ownership than nonmembers. This finding suggested that bikesharing was attractive to car owners. Recommendations for improving bikesharing in Hangzhou included adding stations and real-time bike and parking availability technologies, improving bike maintenance and locking mechanisms, and extending operational hours.

High‐resolution mapping of motor vehicle carbon dioxide emissions

A fuel-based inventory for vehicle emissions is presented for carbon dioxide (CO2) and mapped at various spatial resolutions (10 km, 4 km, 1 km, and 500 m) using fuel sales and traffic count data. The mapping is done separately for gasoline-powered vehicles and heavy-duty diesel trucks. Emission estimates from this study are compared with the Emissions Database for Global Atmospheric Research (EDGAR) and VULCAN. All three inventories agree at the national level within 5%. EDGAR uses road density as a surrogate to apportion vehicle emissions, which leads to 20–80% overestimates of on-road CO2 emissions in the largest U.S. cities. High-resolution emission maps are presented for Los Angeles, New York City, San Francisco-San Jose, Houston, and Dallas-Fort Worth. Sharp emission gradients that exist near major highways are not apparent when emissions are mapped at 10 km resolution. High CO2 emission fluxes over highways become apparent at grid resolutions of 1 km and finer. Temporal variations in vehicle emissions are characterized using extensive day- and time-specific traffic count data and are described over diurnal, day of week, and seasonal time scales. Clear differences are observed when comparing light- and heavy-duty vehicle traffic patterns and comparing urban and rural areas. Decadal emission trends were analyzed from 2000 to 2007 when traffic volumes were increasing and a more recent period (2007–2010) when traffic volumes declined due to recession. We found large nonuniform changes in on-road CO2 emissions over a period of ~5 years, highlighting the importance of timely updates to motor vehicle emission inventories.

PUBLIC BIKESHARING IN NORTH AMERICA: EARLY OPERATOR UNDERSTANDING AND EMERGING TRENDS

Public bikesharing, the shared use of a bicycle fleet by the public, is an innovative mobility strategy that has emerged recently in major North American cities. Typically, bikesharing systems position bicycles throughout an urban environment, within a network of docking stations, for immediate access. Bikesharing services with a basis in information technology (IT) began to emerge in North America approximately 5 years ago. Twenty-eight IT-based programs were deployed between 2007 and March 2013. Twenty-four are operational, two are temporarily suspended, and two are now defunct. This study examined the growth potential of bikesharing in North America on the basis of a survey of all 15 IT-based public bikesharing systems in operation in the United States and all four programs deployed in Canada as of January 2012. These programs accounted for 172,070 users and 5,238 bicycles in the United States and for 44,352 users and 6,235 bicycles in Canada. Early operator understanding of North American public bikesharing is reviewed and emerging trends for prospective program start-ups are discussed.

Carsharing Parking Policy: Review of North American Practices and San Francisco, California, Bay Area Case Study

Carsharing provides users access to a shared vehicle fleet for short-term use throughout the day, reducing the need for private vehicles. The provision of on-street and public off-street parking dedicated to carsharing is an important policy area confronting public agencies. As of July 2009, approximately 377,600 individuals were carsharing members in North America in about 57 metropolitan areas. Seventeen jurisdictions, one state (California), and eight public transit operators in North America have formal and informal carsharing parking policies, pilot projects, and proposed legislation. These policies, projects, and proposals are reviewed in this paper, along with a framework for carsharing parking policy that reflects three levels of government support. In addition, the authors examine carsharing parking policies in three jurisdictions in the San Francisco Bay Area in California that account for an estimated 50,000 carsharing members and 1,100 shared-use vehicles. Supporting this examination is an intercept survey on carsharing parking (n = 425) conducted in the Bay Area. Most people supported the conversion of some type of spaces for carsharing use, and 48% thought that carsharing organizations should compensate the city for on-street spaces. At the same time, converting most types of spaces was opposed by at least 20% of respondents. Neighborhood residents were generally more in favor of parking conversion for carsharing than people visiting the area for work or errands. Finally, a majority (61%) thought that nonprofits should have priority over for-profit organizations for carsharing spaces and should pay less than for-profit organizations.

Carsharing in Shanghai, China: analysis of behavioral response to a local survey and potential competition

The rapid motorization of China raises questions about the potential for alternative mobility solutions, such as carsharing (short-term auto use), used in developing megacities such as Shanghai. Demand for motor vehicles is increasing rapidly, but many aspects of urban transportation in Shanghai and in China more broadly separate the city and the center from other urban environments in which carsharing has thrived traditionally. For example, the taxi is much more prominent in the transportation systems of Shanghai and Beijing than in most North American and European cities. Carsharing tends to thrive in environments in which the broad population has experience with driving and automobile ownership. This experience is lacking in Shanghai. To evaluate carsharings potential in Shanghai, the size and competitiveness of the taxi systems of key carsharing cities in Europe, North America, and Asia were compared. The analysis illustrated core distinctions between Shanghai and other major cities in which carsharing has thrived. To explore further the potential response of Shanghais citizens to carsharing, a survey was conducted (N = 271) of a subpopulation in Shanghai from November 2010 to February 2011. The survey analysis showed that those interested in carsharing were younger, more likely to be educated, had longer commutes, and owned fewer cars than those with no interest in carsharing. This paper concludes with a discussion of this studys implications for the development of a carsharing industry in Shanghai.

How Public Education on Ecodriving Can Reduce Both Fuel Use and Greenhouse Gas Emissions

Ecodriving, the concept of changing driving behavior and vehicle maintenance to affect fuel consumption and greenhouse gas (GHG) emissions in existing vehicles, has recently gained prominence in North America. One ecodriving strategy involves public education with information disseminated on the Internet. This paper presents the results of a study conducted from June to December 2010 that assessed the effectiveness of static, web-based information on ecodriving with controlled stated responses from approximately 100 faculty, staff, and students at the University of California, Berkeley. A comparison of the experimental and control groups revealed that exposure to ecodriving information influenced peoples driving behavior and maintenance practices. The experimental groups distributional shift in behavior was statistically significant, particularly for key practices, including lower highway cruising speed, adjustment of driving behavior, and proper tire inflation. Within the experimental group (N = 51), only 16% of respondents significantly changed their maintenance practices whereas 71% altered some driving practices; these data suggest that intentional alteration of driving behavior is easier than is planning better maintenance practices. A comparison of before-and-after surveys revealed that 57% of the experimental group improved their ecodriving behavior and that 43% made no change or worsened. Key characteristics of the drivers who improved included being female, living in smaller households, and owning a newer car with higher fuel economy. Although it was evident that not everyone modified behavior as a result of reviewing the website, even small shifts in behavior attributable to inexpensive dissemination of information could be deemed cost-effective in reducing fuel consumption and emissions.

Demand for Carsharing Systems in Beijing, China: An Exploratory Study

ABSTRACT Rising auto ownership in China brings significant urban and environmental challenges. Since China is still in the early stages of motorization, there are opportunities to introduce alternatives to personal vehicle ownership. The authors conducted a survey with 800 Beijing residents, collecting data on transportation patterns, automobile ownership, environmental attitudes, and carsharing response. Fifteen of those participants were selected to complete an in-depth questionnaire discussing how they would use carsharing services. This paper assesses the potential for carsharing systems within Beijing, China, based on this exploratory study. While the results suggest that carsharing models integrated into existing transit networks could become an important mobility option within Chinas rapidly growing cities, further study is recommended.

Smartphone App Evolution and Early Understanding from a Multimodal App User Survey

Travelers are increasingly turning to smartphone applications for an array of transportation functions. Four types of transportation apps have emerged: (1) mobility apps; (2) connected vehicle apps; (3) smart-parking apps; and (4) courier network service (CNS) apps. This chapter discusses the history and trends leading to the growth and development of transportation apps and summarizes key characteristics of 83 transportation apps identified through an Internet search cataloging transportation apps with more than 10,000 downloads each. Seventy-one percent of the 83 apps identified incorporated a real-time data function (e.g., traffic conditions, roadway incidents, parking availability, and public transit wait times). Additionally, the chapter reports on findings from a survey, conducted in spring 2016, of 130 app users who downloaded the RideScout mobility aggregator app (which ceased operations in August 2016). The survey, which asked respondents questions about their use of mobility aggregators more generally, sought to understand how multi-modal information apps shift travel behavior. The findings showed that most users of such apps would walk, drive alone, and carpool during a typical month. Fifty percent of respondents drove alone once or more per day. Twenty-five percent owned one vehicle, and 75% owned two or more vehicles. Thirty-nine percent of respondents reported that they drove less or much less due to the apps. Findings from the survey suggest that multi-modal app users do change their travel behavior in response to information provided, and they may contribute to a reduction in vehicle use.