by Natalie Chyba | Dec 1, 2011 |
Authors: Elliot Martin, Susan Shaheen Date: December 01, 2011 Abstract: This paper evaluates the greenhouse gas (GHG) emission impacts that result from individuals participating in carsharing organizations within North America. The authors conducted 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....
by Natalie Chyba | Nov 15, 2011 |
Authors: Mingquan Wang, Elliot Martin, and Susan Shaheen Date: November 15, 2011 Abstract: The rapid motorization of China raises questions about the potential for alternative mobility solutions, such carsharing (short-term auto use), in developing mega cities like Shanghai, with a population of over 17 million people. While motor vehicle demand is increasing rapidly, there are many aspects of urban transportation in Shanghai (and China more broadly) that separate it from the urban environments in which carsharing has traditionally thrived. For example, the taxi plays a much more prominent role in the transportation system of Shanghai and Beijing than it does in most North American and European cities. Carsharing has also traditionally thrived in environments in which the broader population has experience with both driving and automotive ownership, which is relatively lacking in Shanghai. To evaluate carsharing’s potential in Shanghai, the authors comparatively analyze the size and competitiveness of the taxi systems of key carsharing cities in Europe, North America, and Asia and highlight some core distinctions between Shanghai and other major cities where carsharing has thrived. To further explore the potential response of citizens to carsharing, the authors conducted a survey (N=271) of a subpopulation in Shanghai. The survey analysis shows that those interested in carsharing are younger, more likely to be educated, have longer commutes, and own fewer cars than those not interested in carsharing. Following analysis of the survey data, the authors conclude with a discussion of the implications of these results for the development of the carsharing industry in Shanghai. View...
by Natalie Chyba | Nov 1, 2011 |
Authors: Elliot Martin and Susan Shaheen Date: December 1, 2011 Abstract: By July 2011, North American carsharing had grown to an industry of nearly 640,000 members since its inception on the continent more than 15 years ago. Carsharing engenders changes in member travel patterns both towards and away from public transit and non-motorized modes. This study, which builds on the work of two previous studies, evaluates this shift in travel based on a 6281 respondent survey completed in late-2008 by members of major North American carsharing organizations. Across the entire sample, the results showed an overall decline in public transit use that was statistically significant, as 589 carsharing members reduced rail use and 828 reduced bus use, while 494 increased rail use and 732 increased bus use. Thus for every five members that use rail less, four members use rail more, and for every 10 members that ride a bus less, almost nine members ride the bus more. The people increasing and decreasing their transit use are fundamentally different in terms of how carsharing impacts their travel environment. This reduction, however, is also not uniform across all organizations; it is primarily driven by a minority (three of eleven) of participating organizations. At the same time, members exhibited a statistically significant increase in travel by walking, bicycling, and carpooling. Across the sample, 756 members increased walking versus a 568 decrease, 628 increased bicycling versus a 235 decrease, and 289 increased carpooling versus a decrease of 99 study participants. The authors found that 970 members reduced their auto commuting to work, while 234 increased it. Interestingly, when these shifts are combined across modes, more...
by Natalie Chyba | Dec 1, 2010 |
Authors: Susan Shaheen, Adam Cohen, and Elliot Martin Date: December 01, 2010 Abstract: 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 (n425) 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. View...
by Natalie Chyba | Jun 1, 2010 |
Authors: Susan Shaheen and Elliot Martin Date: June 01, 2010 Abstract: This report presents the results of a study evaluating the greenhouse gas (GHG) emission changes that result from individuals participating in a carsharing organization. The principle of carsharing is simple: individuals gain the benefits of private vehicle use without the costs and responsibilities of ownership. Carsharing is most common in major urban areas where transportation alternatives are easily accessible. Individuals typically access vehicles by joining an organization that maintains a fleet of cars and light trucks deployed in lots located within neighborhoods, public transit stations, employment centers, and colleges/universities. In this study, the authors conducted a survey of carsharing members across the country to develop a robust estimate of GHG emission impacts resulting from carsharing. The results illustrate the annualized change in GHG emissions among members within the largest carsharing organizations across Canada and the United States. GHG emissions from transportation are lower due to carsharing. The average change in emissions across all respondents is -0.58 t GHG per household per year for the observed impact, and -0.84 t GHG per household per year for the full impact. However, it is important that this result is understood in the context of the broad diversity of carsharing impacts. While carsharing does facilitate lower emissions, the reduction is not generalizable across all members or even a majority of members. Rather, carsharing as a system facilitates large reductions in the annual emissions of some households, which compensate for the collective small emission increases of other households. The results also show that respondent households exhibit significant reductions in vehicle ownership after joining carsharing....
