How Car Sharing affects Safety
Carshare may, relative to private auto travel, confer some safety benefits. For example,users generally have to go through a screening process to sign up for the programs and establish valid licenses. Safe driving behavior does, of course, vary by individual; a study of Australian carshare users found that infrequent users, users in households that owned other cars, and users that had fewer previous accidents, chose more expensive vehicle insurance, and had been licensed for longer, were less likely to be in a vehicle crash [1]. To enhance safety, the study recommended establishing incentives for carshare users with more driving experience and more extensive insurance [1].
More research may be necessary to better establish safety differences among carshare users, whether carshare users travel more safely relative to private vehicle owners, and if so, what the mechanisms are that promote additional precautions while driving.
How Car Sharing affects Health
Carsharing may reduce air pollution (and thus provide public health benefits) by complementing public transit use and providing a substitute for private car-ownership. While some people use carsharing to replace public transit, more people increase their public transit and non-motorized trips (like walking and biking) after joining carsharing [1]. A case study of carsharing in Palermo showed a 25 percent reduction in particulate matter (PM10) and 38 percent reduction in carbon dioxide emissions from the shift from private to shared cars [2]. Survey-based estimates have shown that a carshare vehicle tends to replace roughly 15 private vehicles [3], [4].
Carsharing may have also provided public health benefits related to the COVID-19 pandemic. At the beginning of the COVID-19 pandemic public transit was seen as high-risk for exposure, and people with high incomes disproportionately switched from public transit to cars [5], [6], [7]. Carsharing may have provided an alternative for people without a private vehicle, as surveys show that car sharing was preferred over public transit and taxis due to reduced exposure risk [8].
Areas for further research include the impact of carsharing on access to healthcare and other basic needs and services, as well as accessibility of carsharing across groups.
How Car Sharing affects Land Use
Carshare is particularly useful for people who either live in car-dependent areas and cannot afford a private vehicle, or for urban car-less people who enjoy a diverse array of transportation options that they supplement with driving for trips that require longer-distances, multiple stops, or more storage capacity [1], [2]. Carshare benefits from economies of scale in densely populated cities, and firms can more easily adjust their prices and grow their network flexibly according to consumer demand. Carshare is particularly effective when parking is scarce, there are transit hubs nearby, and land uses are mixed [3]. In lower-density areas, carshare can be more challenging to implement, as people are more likely to enjoy plentiful parking, own their own cars, and have fewer alternatives to driving that would make them more likely to choose to forgo private vehicles [4].
How Car Sharing affects Municipal Budgets
The limited research on carsharing and municipal budgets largely focuses on the tax burden of services in a community. High sales taxes on carshare program might, in the short term, bolster city budgets, but may in the longer run limit the financial sustainability of carshare programs. In a cost-benefits analysis of carshare sales taxes, one study found that sales tax revenue for carshare reservations typically exceeded the nominal sales tax rate [1]. An update to this study found that in keeping with this trend, as retail taxes increased, base price rates for carsharing dropped between 2021-2016, and, as a result, limited the long term sustainability and growth of the carshare sector [2]. Research is significantly lacking in understanding the benefits or costs to city governments and municipal budgets from such services, and how to balance municipal interests with long term sustainability and profitability of services.
How Car Sharing affects Social Equity
By shifting mobility costs to a per-trip basis, carshare offers benefits for users in two categories: those with a car seeking to drive less (by offering access to a private vehicle without the need for ownership), and those without a car seeking to drive more (by reducing the upfront costs of private automobility). Carshare users tend to be car-less yet relatively affluent [1], which can be explained in part by where carshare stations are placed. Studies find that carshare stations are more likely to be located in higher-income neighborhoods with higher-than-average rates of employment and levels of education [2], [3]. Early carshare adopters tended to be white [4]. However, as the market has matured, recent evidence suggests that after controlling for income, Black and Asian travelers are more likely to use carshare than white travelers [5]. Carshare programs with public subsidies that enable reduced rates for eligible low-income residents are a promising policy solution; they can help people who could most benefit from additional automobility, while expanding carshare stations for all users [6].
How Car Sharing affects Transportation Systems Operations
Carsharing can increase the efficiency of the transportation system by allowing multiple individuals to access a single vehicle that uses a single parking space [1]. As with many transportation modes, carsharing serves different needs under different conditions within a broader transportation system. For example, carsharing works well in communities with low vehicle ownership rates [2] or co-located with bus services and areas that have mobility constraints in accessing metro services [3]. Additional research is needed to determine what specific pricing conditions and when and how public or privately-operated carsharing can be sustainable.
How Car Sharing affects Energy and Environment
Carshare’s emissions and fuel consumption depend on several factors, including the types of trips they are substituting for, how many new trips they generate, and how the vehicles are fueled. User demographics play a key role in determining these factors; for example, if people are primarily joining a carshare to shed their private car or delay purchasing one and thus reduce their overall car trips, then the program may reduce emissions [1]. If, however, users generally come from car-less or car-lite households, joining the carshare program may create more trips than subtract them, and thus may increase emissions. Carshare programs that use electric vehicles, such as BlueLA, reduce tailpipe emissions [2]. Electric carshare programs also expose users to cleaner vehicle types, and carshare users are more likely to later select electric cars when purchasing a vehicle than non-users [2]. However, even zero-emission vehicles generate fine air particulate emissions from tire friction, which worsens local air quality.
Carshares can offer emissions and energy savings by reducing net private automobile travel and by replacing more polluting private fleets with cleaner shared fleets. While some carshare trips replace public transit trips, in aggregate and when taking the life cycle energy and emissions impacts into account, carshares reduce net household greenhouse gas emissions [3]. One study found a majority of surveyed North American carshare users traveled more by car after joining the program, thus increasing emissions, but that those emissions increases were outweighed by emissions saved by users who gave up their personal cars [1]. Studies find that a carshare vehicle tends to replace approximately 15 private vehicles [4], [5]. Carshare vehicles may also be more fuel efficient than the overall private car fleet [6]. Another study, based on the same survey of North American carshare users, found a significant increase in walking, cycling and carpooling among people who joined a carshare [7].
While the market for zero emissions vehicles is growing, zero emission vehicles still exceed the budgets of some low-income potential drivers. Electric carshare programs offer a low-risk way to improve access to clean mobility among car-light or car-free households, without requiring users to pay the full costs of owning and maintaining their own electric vehicle [8].
In disadvantaged communities with especially high rates of air pollution, electric carshare programs may help reduce localized air pollution [9].
How Car Sharing affects Education and Workforce
Following the historical research gaps on carsharing, Shaheen [1] recommended longitudinal monitoring to better understand market developments and social and environmental impacts due to growth and policymakers’ interests. For a brief period of time, carshare literature focused on workforce development and labor conditions related to rebalancing in one-way carsharing systems [2]. Today, carsharing evolving with the rise of shared autonomous vehicles have created a gap in research. More research is needed to understand how drivers, barriers, and carsharing will be impacted with autonomous vehicles [3]. Chan and Shaheen [4] predict that carsharing in the next decade will include greater interoperability among services, technology integration and stronger policy support [4]. Understanding how carsharing will develop and its impact can help inform policy related to education and workforce development. However, literature explicitly related to education and workforce development was nonexistent which reveals a major research gap.
How Car Sharing affects Safety
Carshare may, relative to private auto travel, confer some safety benefits. For example,users generally have to go through a screening process to sign up for the programs and establish valid licenses. Safe driving behavior does, of course, vary by individual; a study of Australian carshare users found that infrequent users, users in households that owned other cars, and users that had fewer previous accidents, chose more expensive vehicle insurance, and had been licensed for longer, were less likely to be in a vehicle crash [1]. To enhance safety, the study recommended establishing incentives for carshare users with more driving experience and more extensive insurance [1].
More research may be necessary to better establish safety differences among carshare users, whether carshare users travel more safely relative to private vehicle owners, and if so, what the mechanisms are that promote additional precautions while driving.
How Car Sharing affects Health
Carsharing may reduce air pollution (and thus provide public health benefits) by complementing public transit use and providing a substitute for private car-ownership. While some people use carsharing to replace public transit, more people increase their public transit and non-motorized trips (like walking and biking) after joining carsharing [1]. A case study of carsharing in Palermo showed a 25 percent reduction in particulate matter (PM10) and 38 percent reduction in carbon dioxide emissions from the shift from private to shared cars [2]. Survey-based estimates have shown that a carshare vehicle tends to replace roughly 15 private vehicles [3], [4].
Carsharing may have also provided public health benefits related to the COVID-19 pandemic. At the beginning of the COVID-19 pandemic public transit was seen as high-risk for exposure, and people with high incomes disproportionately switched from public transit to cars [5], [6], [7]. Carsharing may have provided an alternative for people without a private vehicle, as surveys show that car sharing was preferred over public transit and taxis due to reduced exposure risk [8].
Areas for further research include the impact of carsharing on access to healthcare and other basic needs and services, as well as accessibility of carsharing across groups.
How Car Sharing affects Land Use
Carshare is particularly useful for people who either live in car-dependent areas and cannot afford a private vehicle, or for urban car-less people who enjoy a diverse array of transportation options that they supplement with driving for trips that require longer-distances, multiple stops, or more storage capacity [1], [2]. Carshare benefits from economies of scale in densely populated cities, and firms can more easily adjust their prices and grow their network flexibly according to consumer demand. Carshare is particularly effective when parking is scarce, there are transit hubs nearby, and land uses are mixed [3]. In lower-density areas, carshare can be more challenging to implement, as people are more likely to enjoy plentiful parking, own their own cars, and have fewer alternatives to driving that would make them more likely to choose to forgo private vehicles [4].
How Car Sharing affects Municipal Budgets
The limited research on carsharing and municipal budgets largely focuses on the tax burden of services in a community. High sales taxes on carshare program might, in the short term, bolster city budgets, but may in the longer run limit the financial sustainability of carshare programs. In a cost-benefits analysis of carshare sales taxes, one study found that sales tax revenue for carshare reservations typically exceeded the nominal sales tax rate [1]. An update to this study found that in keeping with this trend, as retail taxes increased, base price rates for carsharing dropped between 2021-2016, and, as a result, limited the long term sustainability and growth of the carshare sector [2]. Research is significantly lacking in understanding the benefits or costs to city governments and municipal budgets from such services, and how to balance municipal interests with long term sustainability and profitability of services.
How Car Sharing affects Social Equity
By shifting mobility costs to a per-trip basis, carshare offers benefits for users in two categories: those with a car seeking to drive less (by offering access to a private vehicle without the need for ownership), and those without a car seeking to drive more (by reducing the upfront costs of private automobility). Carshare users tend to be car-less yet relatively affluent [1], which can be explained in part by where carshare stations are placed. Studies find that carshare stations are more likely to be located in higher-income neighborhoods with higher-than-average rates of employment and levels of education [2], [3]. Early carshare adopters tended to be white [4]. However, as the market has matured, recent evidence suggests that after controlling for income, Black and Asian travelers are more likely to use carshare than white travelers [5]. Carshare programs with public subsidies that enable reduced rates for eligible low-income residents are a promising policy solution; they can help people who could most benefit from additional automobility, while expanding carshare stations for all users [6].
How Car Sharing affects Transportation Systems Operations
Carsharing can increase the efficiency of the transportation system by allowing multiple individuals to access a single vehicle that uses a single parking space [1]. As with many transportation modes, carsharing serves different needs under different conditions within a broader transportation system. For example, carsharing works well in communities with low vehicle ownership rates [2] or co-located with bus services and areas that have mobility constraints in accessing metro services [3]. Additional research is needed to determine what specific pricing conditions and when and how public or privately-operated carsharing can be sustainable.
How Car Sharing affects Energy and Environment
Carshare’s emissions and fuel consumption depend on several factors, including the types of trips they are substituting for, how many new trips they generate, and how the vehicles are fueled. User demographics play a key role in determining these factors; for example, if people are primarily joining a carshare to shed their private car or delay purchasing one and thus reduce their overall car trips, then the program may reduce emissions [1]. If, however, users generally come from car-less or car-lite households, joining the carshare program may create more trips than subtract them, and thus may increase emissions. Carshare programs that use electric vehicles, such as BlueLA, reduce tailpipe emissions [2]. Electric carshare programs also expose users to cleaner vehicle types, and carshare users are more likely to later select electric cars when purchasing a vehicle than non-users [2]. However, even zero-emission vehicles generate fine air particulate emissions from tire friction, which worsens local air quality.
Carshares can offer emissions and energy savings by reducing net private automobile travel and by replacing more polluting private fleets with cleaner shared fleets. While some carshare trips replace public transit trips, in aggregate and when taking the life cycle energy and emissions impacts into account, carshares reduce net household greenhouse gas emissions [3]. One study found a majority of surveyed North American carshare users traveled more by car after joining the program, thus increasing emissions, but that those emissions increases were outweighed by emissions saved by users who gave up their personal cars [1]. Studies find that a carshare vehicle tends to replace approximately 15 private vehicles [4], [5]. Carshare vehicles may also be more fuel efficient than the overall private car fleet [6]. Another study, based on the same survey of North American carshare users, found a significant increase in walking, cycling and carpooling among people who joined a carshare [7].
While the market for zero emissions vehicles is growing, zero emission vehicles still exceed the budgets of some low-income potential drivers. Electric carshare programs offer a low-risk way to improve access to clean mobility among car-light or car-free households, without requiring users to pay the full costs of owning and maintaining their own electric vehicle [8].
In disadvantaged communities with especially high rates of air pollution, electric carshare programs may help reduce localized air pollution [9].
How Car Sharing affects Education and Workforce
Following the historical research gaps on carsharing, Shaheen [1] recommended longitudinal monitoring to better understand market developments and social and environmental impacts due to growth and policymakers’ interests. For a brief period of time, carshare literature focused on workforce development and labor conditions related to rebalancing in one-way carsharing systems [2]. Today, carsharing evolving with the rise of shared autonomous vehicles have created a gap in research. More research is needed to understand how drivers, barriers, and carsharing will be impacted with autonomous vehicles [3]. Chan and Shaheen [4] predict that carsharing in the next decade will include greater interoperability among services, technology integration and stronger policy support [4]. Understanding how carsharing will develop and its impact can help inform policy related to education and workforce development. However, literature explicitly related to education and workforce development was nonexistent which reveals a major research gap.