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Electric vehicle charging equity and accessibility: A comprehensive United States policy analysis

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... The prioritization of corridor sites has previously been critiqued. Carlton and Sultana [25] pointed out a grey area overlooked by the Justice40 framework, where the National Electric Vehicle Infrastructure (NEVI) program was fully, and the Charging and Fueling Infrastructure (CFI) Discretionary Grant Program was primarily, focused on alternative fuel corridors for charger installation, leading to issues of overconcentration. In the U.S., census tracts located near corridors are likely to have 2.7 times more overall public chargers and 5.3 times more fast chargers [25]. ...
... Carlton and Sultana [25] pointed out a grey area overlooked by the Justice40 framework, where the National Electric Vehicle Infrastructure (NEVI) program was fully, and the Charging and Fueling Infrastructure (CFI) Discretionary Grant Program was primarily, focused on alternative fuel corridors for charger installation, leading to issues of overconcentration. In the U.S., census tracts located near corridors are likely to have 2.7 times more overall public chargers and 5.3 times more fast chargers [25]. This gap is even more pronounced in rural areas than in urban ones [15], [25]. ...
... In the U.S., census tracts located near corridors are likely to have 2.7 times more overall public chargers and 5.3 times more fast chargers [25]. This gap is even more pronounced in rural areas than in urban ones [15], [25]. The limitations of state-centric programs underscore the shortcomings of a reformist orientation in equity analysis, emphasizing the need for community-led and justice-driven alternatives [25], [26]. ...
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This study explores the integration of AI in transportation electrification planning in Austin, TX, focusing on the use of Geospatial AI (GeoAI), Generative AI (GenAI), and Large Language Models (LLMs). GeoAI enhances site selection, localized GenAI models support meta-level estimations, and LLMs enable scenario simulations. These AI applications require human oversight. GeoAI outputs must be evaluated with land use data, GenAI models are not always accurate, and LLMs are prone to hallucinations. To ensure accountable planning, human planners must work alongside AI agents. Establishing a community feedback loop is essential to audit automated decisions. Planners should place Community Experience (CX) at the center of Urban Planning AI.
... Similar to gas stations, public chargers are mainly operated by private vendors. However, expanding the charging infrastructure and installing additional public chargers often requires government funding (Carlton and Sultana 2024). This expansion typically involves a high level of coordination across multiple government agencies, such as transportation, energy, and environmental departments, along with public engagement efforts involving a range of stakeholders, including advocacy groups, nonprofit organizations, and private vendors (TxDOT 2023). ...
... Living in urban or suburban areas is also related to the issue of unequal access to public EV charging (Jiao et al. 2024b). In fact, Carlton and Sultana (2024) reported that 60-80% of the census tracts in the U.S. do not have adequate access to public EV chargers. This has sparked a normative debate among scholars about how to effectively address and mitigate the issue of distributional inequality. ...
... While measuring accessibility inequality has been of keen interest to scholars, this does not mean that other conceptual frameworks have been neglected. Sufficietarian philosophical approaches have also been applied in policy initiatives, setting thresholds or baselines that should be met, such as in federal policies like Justice40 in the U.S. (Carlton and Sultana 2024). Soltani Mandolakani and Singleton (2024) further explored the application of equity and justice theories, showing how different theoretical frameworks, when applied in practice, can lead to varying policy outcomes. ...
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Public electric vehicle charging stations (EVCSs) are vital for boosting EV adoption. This study investigates Seoul’s public EV charging patterns, taking into account the surrounding urban built environment. We collected built-environment data from land-use maps, Point of Interest (POI) data, and panorama images near public EVCS. The computer-vision technique was used to extract scene features from panorama images. We conducted a spatiotemporal analysis of public EVCS usage. The built-environment factors underwent dimensionality reduction and were assessed for outliers. Descriptive analysis revealed afternoon peak charging times and variations between chargers. Additional peaks are observed in the weekday late evening for chargers located near mega-retail stores. Public EVCS in Seoul were utilized more on weekdays than on weekends. Public EVCS in central business districts saw the most significant usage, with potential cases of overuse. An analysis of the built environment around the chargers showed unique characteristics, with some forming identifiable clusters. The most used public EVCS had more parking areas than other POIs, matching visual observations. Computer visioning mainly recognized highways, parking lots, and crosswalks as common features near the chargers. Outlier test results generally defined fast chargers in the central business district area as outliers. The results also demonstrated that built-environment measures from POI data and computer vision can be used in a complementary manner. Our study offers empirical findings to enhance the understanding of public EV charging usage. We demonstrated the use of POI data and computer-vision techniques to quantify the built environment.
... It has been widely adopted in planning practice and policy-making, due to its interpretability and comparability. In the few existing studies on the accessibility of charging infrastructure in recent years, most have primarily focused on China [7,22,27], Europe [8,28], and the United States [29][30][31][32], which are the top three countries (regions) globally in terms of charging infrastructure distribution [2]. Based on the content of these studies, they can be divided into two aspects, according to scale differences. ...
... Based on the content of these studies, they can be divided into two aspects, according to scale differences. On one hand, some research measures the unequal distribution of charging infrastructure across regions, such as between countries or within domestic regional differences, as well as the urban-rural divide [14,28,30]. On the other hand, some studies focus on measuring facility inequality within cities, often using communities or census tracts as the basic unit of analysis [7,22,27,29]. ...
... Within cities, considering the competition between units and the supply capacity of facilities, population density and the number of chargers (or charging capacity) are used to represent the demand and supply levels of charging behavior. In terms of research methodologies, the two-step floating catchment area (2SFCA) model, the Gaussian-based two-step floating catchment area (G2SFCA) model, and the least-cost path algorithm have been utilized in recent years to examine spatial differences in EVCS accessibility [7,8,27,29,30,33]. Among these methods, the 2SFCA model and its improved variants account for regional competition and the supply capacity of service facilities, often using population density and service capacity metrics (e.g., number of charger, station charging capacity, and number of vehicle turnover) to represent the demand and supply levels of charging behavior [7,8,33]. ...
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The deployment of electric vehicle charging stations (EVCSs) is crucial for the large-scale adoption of electric vehicles and the sustainable energy development of global cities. However, existing research on the spatial distribution of EVCSs has provided limited analysis of spatial equity from the perspective of supply–demand relationships. Furthermore, studies examining the influence of the built environment on EVCS accessibility are scarce, and often rely on single methods and perspectives. To explore the spatial characteristics of EVCS accessibility and its influencing factors, using multi-source urban spatial data, this study initially employs the Gaussian two-step floating catchment area (G2SFCA) method to measure and analyze the spatial distribution characteristics of EVCS accessibility in Guangzhou, China, with consideration of supply–demand relationships. Subsequently, it integrates the MGWR and random forest (RF) models to comprehensively investigate the impact mechanism of the built environment on EVCS accessibility from the perspectives of spatial heterogeneity and non-linear relationship. The results show that the EVCS accessibility exhibits a “ higher in the west and lower in the east, with extreme core concentration” distribution pattern, and has significant spatial autocorrelation. The built-environment variables exhibit different scale effects and spatial non-stationarity, with widespread non-linear effects. Among them, the auto service, distance to regional center, and distance to subway station play important roles in influencing EVCS accessibility. These findings offer important guidance for the efficient and equitable layout of EVCSs in high-density cities.
... Recent policies and technological advancements have not only reduced EV costs and extended their driving ranges (Onstad, 2024) but also expanded the charging infrastructure, significantly increasing adoption rates (The White House, 2021 Despite this progress, the placement of EV charging stations often favors affluent urban areas, neglecting lower-demand rural and inner-city regions (Khan et al., 2022). This mismatch hinders accessibility for about 60-80% of U.S. census tracts that lack public charging facilities, contradicting federal equity objectives (Carlton and Sultana, 2024). The Biden-Harris administration aims to install 500,000 EV charging stations, emphasizing the need for equitable distribution to support all communities, especially those in rural areas where there is a strong proenvironmental commitment but inadequate infrastructure (Huether, 2021;The White House, 2021). ...
... Studies show a strong pro-environmental commitment in rural areas, suggesting high potential for EV adoption (Berenguer, Corraliza and Martín, 2005). Despite this, the market-driven placement of EV charging stations (EVSE) frequently neglects lower-demand rural and inner-city areas, leading to inadequate infrastructure that doesn't support mobility needs (Mortimer et al., 2022;Carlton and Sultana, 2024). Additionally, even as charging corridors expand fast charging access, about 60-80% of U.S. census tracts still lack public charging facilities, indicating a disconnect with federal equity objectives (Carlton and Sultana, 2024). ...
... Despite this, the market-driven placement of EV charging stations (EVSE) frequently neglects lower-demand rural and inner-city areas, leading to inadequate infrastructure that doesn't support mobility needs (Mortimer et al., 2022;Carlton and Sultana, 2024). Additionally, even as charging corridors expand fast charging access, about 60-80% of U.S. census tracts still lack public charging facilities, indicating a disconnect with federal equity objectives (Carlton and Sultana, 2024). ...
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1 The transition to electric vehicles (EVs) to reduce greenhouse gas (GHG) emissions has been a 2 large part of climate policy. EV adoption relies on the charging stations that provide EVs with 3 power. Where public charging stations are placed impacts their utility, and unadvised planning 4 could risk furthering the transportation infrastructure divide between rural and urban areas. This 5 study examines the travel patterns of urban and rural areas to establish the varied need for 6 charging stations and measures the equity of the existing public charging station sites. The use of 7 job access as a measure of rurality reveals both the longer daily mileage traveled by people in 8 rural areas and the influence of job accessibility on trip miles. Public charging stations, or 9 electric vehicle supply equipment (EVSE), however, are concentrated in urban areas and still 10 inaccessible for many consumers. Both the current lack of stations and the higher expected 11 demand for public stations based on travel patterns highlight that more charging stations are 12 especially needed in rural areas. These findings underline the need for policy decisions on the 13 funding and placement of charging stations to be made with care to provide more equal access to 14 EVSE and foster EV adoption everywhere. 15 16
... This creates unequal access and limits EV adoption in disadvantaged areas (Zhou et al. 2022). Approximately 60-80% of U.S. census tracts lack public charging stations, contradicting federal goals of equitable access (Carlton and Sultana 2024). The Pacific Northwest National Laboratory (PNNL) defines an equitable energy system as one that provides economic, health, and social benefits to all individuals, regardless of ability, race, or socio-economic status (Tarekegne et al. 2021). ...
... Tailored EVSE strategies are necessary to address these disparities and encourage broader adoption (Hennessy and Syal 2023;Hsu and Fingerman 2020;Jonas and Macht 2024;Reck 2020). While there is a strong commitment to environmental sustainability, market-driven approaches to EVSE infrastructure frequently overlook rural and underserved urban areas (Berenguer et al. 2005;Carlton and Sultana 2024;Mortimer et al. 2022). To democratize EV adoption and ensure all communities benefit, policy frameworks must incorporate equity and justice, prioritizing access for lower-income and underserved regions (Bauer 2021;Soltani Mandolakani and Singleton 2024). ...
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The transition to electric vehicles (EVs) to reduce greenhouse gas (GHG) emissions has been a large part of climate policy. EV adoption relies on the charging stations that provide EVs with energy. The placement of public charging stations impacts their utility, and unadvised planning could risk furthering the transportation infrastructure divide between rural and urban areas. This study provides an unconventional perspective on the problem. It is argued that the provision of public charging stations, or electric vehicle supply equipment (EVSE), should be considered in the context of the differential ability to substitute private vehicle travel by other modes or land use reforms. We first examine the travel patterns of urban and rural areas, sequentially excluding non-private vehicle then shopping journeys replaceable by online purchases, to establish the varied need for charging stations and measure the equity of the existing public charging station sites. The use of job access as a measure of rurality reveals both the longer daily mileage traveled by people in rural areas and the influence of job accessibility as a proxy for amenity access. An equity framework is formulated based on the classic Lorenz curve, with an extension to jointly consider job and EVSE access via a Cobb-Douglas-style production function. We characterize the state of equity in this production function for the United States as of 2024.
... On the contrary, we consider it a conversion factor because users' ability to pay determines the degree to which they can leverage charging infrastructure, engage in desired activities, and effectively use electrical equipment. Income is the primary measure of financial capacity in EV charging, transport, and energy research (Carlton & Sultana, 2024;Pereira et al., 2017;Sovacool et al., 2018). Across these fields, higher income consistently correlates with better access to charging, activities, and energy. ...
... It also encompasses the influence of design elements and building layouts (microenvironment) in the ease of infrastructure installation and service use, and weather (natural environment) effects on charging access and use. While the spatial distribution of public charging infrastructure is widely studied in literature (Carlton & Sultana, 2024;Hsu & Fingerman, 2021;Khan et al., 2022), our review reveals that there are opportunities for future research to delve deeper into the microenvironment and natural environment effects on charging access. ...
... The pivotal role of EV charging infrastructure in supporting personal vehicle electrification has motivated a growing body of research on its accessibility. Numerous case studies have examined this issue across leading EV markets, including the United States [26,11,15], China [29], and Europe [14], as well as at more localized scales such as California [17,33], Texas [20], Washington [13], and New York City [21]. While these studies are unified in their goal of addressing charging access as a critical concern, they differ considerably in their quantitative frameworks for defining and evaluating accessibility, reflecting diverse methodological choices and regional contexts. ...
... Distance-based measures offer an alternative to count-based approaches by assessing accessibility in terms of the travel distance or travel time between individuals and the nearest EVCS. For example, Carlton et al. [11] calculated travel time to the nearest EVCS for each pixel across the contiguous United States and aggregated the results to the census tract level. Similarly, Lou et al. [26] leveraged a disaggregated dataset of 121 million U.S. household locations to compute the shortest distance to up to five nearby EVCSs for each household. ...
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Electric vehicle (EV) charging infrastructure is crucial for advancing EV adoption, managing charging loads, and ensuring equitable transportation electrification. However, there remains a notable gap in comprehensive accessibility metrics that integrate the mobility of the users. This study introduces a novel accessibility metric, termed Trajectory-Integrated Public EVCS Accessibility (TI-acs), and uses it to assess public electric vehicle charging station (EVCS) accessibility for approximately 6 million residents in the San Francisco Bay Area based on detailed individual trajectory data in one week. Unlike conventional home-based metrics, TI-acs incorporates the accessibility of EVCS along individuals' travel trajectories, bringing insights on more public charging contexts, including public charging near workplaces and charging during grid off-peak periods. As of June 2024, given the current public EVCS network, Bay Area residents have, on average, 7.5 hours and 5.2 hours of access per day during which their stay locations are within 1 km (i.e. 10-12 min walking) of a public L2 and DCFC charging port, respectively. Over the past decade, TI-acs has steadily increased from the rapid expansion of the EV market and charging infrastructure. However, spatial disparities remain significant, as reflected in Gini indices of 0.38 (L2) and 0.44 (DCFC) across census tracts. Additionally, our analysis reveals racial disparities in TI-acs, driven not only by variations in charging infrastructure near residential areas but also by differences in their mobility patterns.
... However, multi-criteria decision-making process often requires substantial input from policymakers and experts, which can introduce subjective biases (Carlton and Sultana, 2024). While domain knowledge is crucial, it is susceptible to biases and subjective interpretations. ...
... However, this approach poses challenges, as decision-makers often struggle to determine binary thresholds. Since CEJST relies on hard thresholds (Carlton and Sultana, 2024) to standardize its analysis, its omission of critical indicators (e.g., race) and binary thresholds compromise the objectivity and inclusivity of its outputs. ...
Article
This paper introduces a unified, data-driven multi-criteria equity metric designed to address inequities in Electric Vehicle Charging Station (EVCS) accessibility and Electric Vehicle (EV) adoption. Existing studies predominantly focus on macro-level factors and rely on single-criterion or context-specific approaches, limiting their applicability to dynamic, multi-dimensional challenges. Additionally, current equity evaluations often involve inherent subjectivity, complicating decision-making processes. Focusing on the Dallas-Fort Worth area, this study advances the field by transitioning from city-level to census tract-level analysis. The proposed framework utilizes dimension reduction techniques to construct a unified equity metric and high-resolution clustering analysis to identify EV-related socio-demographic typologies. These typologies-EV developed, EV developing, and EV underdeveloped/disadvantaged-are validated against disadvantaged communities (DACs) defined by the Climate and Economic Justice Screening Tool (CEJST), mapped EV/EVCS distributions, and their corresponding socio-demographic radar plots. The data-driven equity metric has advantages in unity, objectivity, adaptability, and robustness compared to existing metrics. By identifying micro-level inequities, the framework provides tailored policy recommendations for each typology, supporting equitable EV infrastructure planning.
... Similar findings from U.S. studies show that the availability of EV charging stations is not determined by population density [18,22], but is correlated with median household income [18,[22][23][24] age [22], percentage of white-identifying population [18], and the presence of highways within a zip code area [15,18]. Extended this analysis, where central residents have better access to medium and quick chargers, showed that higher education levels, income, and private housing are linked to more equitable EV charging access. ...
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Electric vehicles (EVs) are rapidly gaining popularity due to their environmental benefits, such as reducing greenhouse gas emissions. Considering the sociodemographic factors that influence the adoption of EVs is essential when developing equitable and efficient transportation policies. This article leverages the National Household Travel Survey (NHTS) 2022 data to analyze the sociodemographic factors influencing the adoption of EVs in the U.S. A binary logistic regression model and three machine learning models were employed to predict EV ownership in the U.S. The results of the regression model suggested that the Pacific division leads in EV adoption, most likely due to legislation and improved infrastructure, while regions such as East South Central suffer from lower EV adoption. The findings indicate that higher household income and home ownership significantly correlate with increased EV adoption. In contrast, renters and rural households exhibit lower adoption rates suggesting an increase in charging facilities in these regions can promote EV adoption. The Random Forest model outperforms others with an accuracy of 82.72%, suggesting its robustness in handling complex relationships between variables. Policy implications include the need for financial incentives for low-income households and increased charging infrastructure in rural and underserved urban areas to promote equitable EV adoption.
... Providing electric mobility solutions to diverse communities can lead to a more inclusive environmental movement, with the advantages of reduced emissions and sustainable living shared by everyone (Pan et al. 2021). This underscores the significance of equitable planning for EV charging infrastructure (Li et al. 2022), especially as the United States embarks on a new era of EV planning bolstered by substantial governmental grant support (Carlton and Sultana 2024). ...
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The transportation sector significantly contributes to greenhouse gas emissions, highlighting the need to transition to Electric Vehicles (EVs) to reduce fossil fuel dependence and combat climate change. The US government has set ambitious targets for 2030, aiming for half of all new vehicles sold to be zero-emissions. Expanding EV charging stations is crucial for this transition, but social equity presents a significant challenge. The Justice40 program mandates that at least 40% of benefits be allocated to disadvantaged communities, ensuring they benefit from federal investments. Given the current concentration of EV ownership in affluent areas, merely installing charging stations in disadvantaged neighborhoods may not suffice. This article explores crowdfunding as a novel method to finance EV charging infrastructure, engaging, and empowering underserved communities. The paper concludes with a hypothetical case showing financing benefits for disadvantaged communities, exploring crowdfunding variations, and scaling to develop equitable EV charging networks.
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Achieving sustainable development goals requires transformative approaches, with transportation offering significant decarbonization potential. While electric vehicle (EV) research has grown rapidly, early studies focused on bibliometric trends or impact of policies on EV adoption, neglecting the reverse dynamic—how research shapes policy. This paper fills this gap by analyzing how EV research influences policy using a methodological framework. A dataset of 44,246 Scopus articles, cross-referenced with Overton database quantifies the policy impact of EV research, identifying key contributors such as influential journals (Transportation Research Part A & D, Energy Policy), authors, and countries. Our findings reveal that articles on cost comparisons, environmental metrics, and integration solutions hold significant policy influence despite low traditional citation counts. Topic modeling highlights policy resonance in studies on battery technology, emission reduction, and grid integration. This work advocates for multi-metric approaches, combining bibliometric and policy impact assessments, to advance science-policy studies and drive societal change.
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The world is running out of time to avoid cataclysmic climate impacts. Therefore, determining which decarbonisation strategies are more effective and inclusive in reducing anthropogenic dependency on fossil fuels is vital for governments’ decisions on investment. This research argues that the electrification of private automobility is neither effective nor equitable. Considering the current electricity mix of the grid, this electrification merely shifts the CO2 emissions and other pollutants from urban to rural areas. The strategy of private automobility electrification does not look beyond the problem of tailpipe emissions and hence cannot eliminate the deficiencies of the car-dependent system that require system-wide solutions, such as traffic congestion and road accidents. Prioritising this strategy not only maintains existing inequities but also increases social injustice and delays the implementation of more effective interventions. We argue that using private EVs structurally violates the biosphere and human communities in three ways: (1) production of inequities, (2) pollution and waste, and (3) the space of the exception (the ‘Electric Vehicle Bubble’). Finally, we conclude that eradicating private automobility is necessary to realise climate and transport justice. Focusing on inclusive strategies, such as supporting public transportation, shared mobility, and active travel modes, instead of offering incentives for EVs, are the means of progressive redistribution of wealth and can satisfactorily meet people’s basic needs and governmental climate targets.
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Background Mapping geographical accessibility to health services is essential to improve access to public health in sub-Saharan Africa. Different methods exist to estimate geographical accessibility, but little is known about the ability of these methods to represent the experienced accessibility of the population, and about the added-value of sophisticated and data-demanding methods over simpler ones. Here we compare the most commonly used methods to survey-based perceived accessibility in different geographical settings. Methods Modelled accessibility maps are computed for 12 selected sub-Saharan African countries using four methods: Euclidean distance, cost-distance considering walking and motorized speed, and Kernel density. All methods are based on open and large-scale datasets to allow replication. Correlation coefficients are computed between the four modelled accessibility indexes and the perceived accessibility index extracted from Demographic and Health Surveys (DHS), and compared across different socio-geographical contexts (rural and urban, population with or without access to motorized transports, per country). Results Our analysis suggests that, at medium spatial resolution and using globally-consistent input datasets, the use of sophisticated and data-demanding methods is difficult to justify as their added value over a simple Euclidian distance method is not clear. We also highlight that all modelled accessibilities are better correlated with perceived accessibility in rural than urban contexts and for population who do not have access to motorized transportation. Conclusions This paper should guide researchers in the public health domain for knowing strengths and limits of different methods to evaluate disparities in health services accessibility. We suggest that using cost-distance accessibility maps over Euclidean distance is not always relevant, especially when based on low resolution and/or non-exhaustive geographical datasets, which is often the case in low- and middle-income countries.
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Background Hospital length of stay (LOS) is a key indicator of hospital care management efficiency, cost of care, and hospital planning. Hospital LOS is often used as a measure of a post-medical procedure outcome, as a guide to the benefit of a treatment of interest, or as an important risk factor for adverse events. Therefore, understanding hospital LOS variability is always an important healthcare focus. Hospital LOS data can be treated as count data, with discrete and non-negative values, typically right skewed, and often exhibiting excessive zeros. In this study, we compared the performance of the Poisson, negative binomial (NB), zero-inflated Poisson (ZIP), and zero-inflated negative binomial (ZINB) regression models using simulated and empirical data. Methods Data were generated under different simulation scenarios with varying sample sizes, proportions of zeros, and levels of overdispersion. Analysis of hospital LOS was conducted using empirical data from the Medical Information Mart for Intensive Care database. Results Results showed that Poisson and ZIP models performed poorly in overdispersed data. ZIP outperformed the rest of the regression models when the overdispersion is due to zero-inflation only. NB and ZINB regression models faced substantial convergence issues when incorrectly used to model equidispersed data. NB model provided the best fit in overdispersed data and outperformed the ZINB model in many simulation scenarios with combinations of zero-inflation and overdispersion, regardless of the sample size. In the empirical data analysis, we demonstrated that fitting incorrect models to overdispersed data leaded to incorrect regression coefficients estimates and overstated significance of some of the predictors. Conclusions Based on this study, we recommend to the researchers that they consider the ZIP models for count data with zero-inflation only and NB models for overdispersed data or data with combinations of zero-inflation and overdispersion. If the researcher believes there are two different data generating mechanisms producing zeros, then the ZINB regression model may provide greater flexibility when modeling the zero-inflation and overdispersion.
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Education researchers often study count variables, such as times a student reached a goal, discipline referrals, and absences. Most researchers that study these variables use typical regression methods (i.e., ordinary least-squares) either with or without transforming the count variables. In either case, using typical regression for count data can produce parameter estimates that are biased, thus diminishing any inferences made from such data. As count-variable regression models are seldom taught in training programs, we present a tutorial to help educational researchers use such methods in their own research. We demonstrate analyzing and interpreting count data using Poisson, negative binomial, zero-inflated Poisson, and zero-inflated negative binomial regression models. The count regression methods are introduced through an example using the number of times students skipped class. The data for this example are freely available and the R syntax used run the example analyses are included in the Appendix. Available freely at: http://pareonline.net/getvn.asp?v=21&n=2
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President Biden has committed to a “whole of government approach” to address environmental and climate justice, which includes directing resources to historically underserved and overburdened populations. The Justice40 program is one of the signature programs in these efforts, requiring that 40 percent of the benefits of designated programs be targeted to disadvantaged communities. Because many federal spending programs that are part of the Justice40 initiative involve the transfer of funds from federal agencies to state governments, the Biden Administration will need the assistance of state officials if the initiative is to achieve its stated objectives. In this article, we study early state implementation of Justice40 in the area of transportation, focusing on the federal highway program and the new National Electric Vehicle Infrastructure (NEVI) program. Our analysis of interviews with state officials and state NEVI plans reveals only modest differences between states in Justice40 implementation based on the partisanship of gubernatorial leadership, despite outspoken resistance to the initiative from many Republican governors. We also find that states that have made previous policy and institutional commitments to allocate resources in a manner similar to Justice40 are generally more receptive to this federal initiative.
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Passenger vehicles are an essential form of transportation and contribute significantly to greenhouse gas emissions and criteria air pollution. The health and climate effects associated with their use disproportionately impact low-income communities and people of color. A shift from conventional vehicles to zero-emission vehicles is essential to meet climate targets and reduce inequities. The transition to clean transportation is an opportunity to uplift underserved and marginalized communities while building a sustainable transportation system. We assess justice in California’s transition to electric passenger vehicles by analyzing publicly available data on electric vehicle adoption and rebate use to measure justice in three areas: distribution of electric vehicles, allocation of state incentives, and the social and historical context of redlining. We find electric vehicle adoption and rebate use are lower in low-income and Latino-majority ZIP codes and in formerly redlined neighborhoods, indicating that California’s electric vehicle transition has not been just thus far.
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The utilization of electric vehicle (EV) charging equipment is a key driver of charging station economics, but current trends and factors related to the utilization of public charging infrastructure in the United States are not well understood. This study analyzes EV charging data from 3,705 nationwide public Level 2 (L2) and direct current fast charging (DCFC) stations over 2.5 years (2019–2022), observing utilization patterns over time. Regression analysis is used to assess the relationships between station utilization and several contextual and environmental factors. We conclude that local EV adoption is a strong indicator of utilization; L2 station utilization decreases with the size of the local charging network, while DCFC stations are less affected; and increased charging power has a greater effect on utilization for DCFC stations than L2. This study fills a critical research gap by reporting updated public charging station utilization statistics and analysis for the U.S. market.
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Many communities have been marginalised in the ongoing policy and planning debates surrounding transportation electrification, even though well allocated charging infrastructure is essential for the environmental and societal benefits of Electric Vehicles (EVs) to be realised. This scoping review aims to synthesise the current state of knowledge and gaps surrounding transportation equity in EV charging research. Following PRISMA-Scr protocols, a literature search is conducted to locate articles that explicitly or implicitly discuss EV charging equity. Our review finds that research on charging equity is nascent and lacking in clear normative evaluations of equity compared to the wider body of transportation equity literature. Only slightly more than one-in-four of an identified 37 articles discuss equity and justice explicitly. Equity perspectives in charging research are dominated by North American and European perspectives, with limited perspectives from the rest of the world. Charging incentivisation schemes and planning efforts may not be equity focused and may favour wealthier individuals, and there are differences in the charging needs and desires of high adoption groups compared to low adoption groups. These findings, however, often come from geographically and philosophically limited contexts and there are gaps in the literature for new methodological and topical contributions to this area. ARTICLE HISTORY
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Supporting the adoption of zero-emission vehicle (ZEVs), including plug-in electric vehicles (EVs), has become a priority for governments due to their ability to reduce petroleum demand, improve air quality, and reduce carbon dioxide (CO2) emissions. Optimal strategies to accelerate EV adoption must weigh the relative value of alternative policy mechanisms to consumers, including public charging infrastructure and vehicle purchase subsidies. We use a historically validated light-duty vehicle consumer choice tool, the ADOPT model, to simulate personal light-duty vehicle adoption and related emissions in California. ADOPT is updated to incorporate a quantification of the tangible value of public charging infrastructure, allowing us to simulate the impact of investments in public charging infrastructure and vehicle purchase subsidies under different scenarios. We show that both policies result in increased EV adoption, with the most effective policy varying depending on vehicle technology assumptions. Under conservative technology improvement assumptions, infrastructure investments are most effective in promoting EV sales and reducing CO2 emissions, while under optimistic technology improvement assumptions a combination of infrastructure and subsidies best supports EV sales and CO2 emission reductions.
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Background In 2015, the Lancet Commission on Global Surgery proposed timely access to surgical care facilities as an indicator of preparedness in surgical systems. Since then, several African and South American countries have mapped the population coverage for their surgical facilities. However, these estimates are missing for India, despite its large population, geographical scope, and sociodemographic diversity. We conducted a nationwide analysis of timely access to surgical care in India and point to rural–urban disparities. Methods We extracted a nationwide dataset of 20 802 geolocated surgical care facilities from the IndoHealMap project. We obtained accessibility motorised friction surface raster data cropped for India from the Malaria Atlas Project Explorer. We calculated the travel times from each grid cell (equivalent to 1 km²) in India to its nearest surgical facility under the optimal speed estimation by means of the Djikstra least-cost algorithm. District-level and state-level rural and urban populations were estimated through raster-based analysis via data from WorldPop, Urban-Rural Catchment Areas, and GADM version 3.6. The primary endpoint of the analysis was the proportion of population within 2 h of their nearest surgical care facility at national, state, and district levels. Wilcoxon tests adjusted for multiple comparisons (Holm-Bonferroni correction) were used to investigate rural-urban differences at a 5% significance level. Findings The motorised travel-times distribution is highly right-skewed, depicting that a large number of areas in India were within 2 h of their nearest surgical facility. At the national level, 99·2% of the rural population had timely access to surgical care facilities, compared with 99·8% of the urban population. However, less than 80% of the rural population in the northern and northeast regions had timely access to care. The rural regions had a significantly smaller proportion of residents with timely access to surgical care compared with their and urban counterparts at the district level (n=1299, effect size=0·57; p<0·001) and state level (n=71, effect size=0·51; p<0·001) analyses. Interpretation Our findings should be considered upper-bound estimates for geographical access because they assume readily available motorised transport and optimal travel speeds, which might not always be the case. These first-ever estimates can inform India's National Surgical, Obstetric, and Anesthesia Plan and which locations should be focused on for upcoming surgical facilities. Funding No funding to declare.
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Access to and affordability of electric vehicle (EV) charging infrastructure are the two prominent barriers for EV adopttion. While major efforts are underway in the United States to roll-out public EV charging infrastructure, persistent social disparities in EV adoption call for interventions. In this paper, we analyze the existing EV charging infrastructure across New York City (NYC) to identify such socio-demographic and transportation features that correlate with the current distribution of EV charging stations. Our results demonstrate that population density is not correlated with the density of EV chargers, hindering New York’s EV adoption and decarbonization goals. On the contrary, the distribution of EV charging stations is heavily skewed against low–income, Black–identifying, and disinvested neighborhoods in NYC, however, positively correlated to presence of highways in a zip code. The results underscore the need for policy frameworks that incorporate equity and justice in the roll-out of EV charging infrastructure.
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Electric vehicles (EVs) are considered a substitute for fossil-fueled vehicles due to rising fossil fuel prices and accompanying environmental concerns, and their use is predicted to increase dramatically shortly. However, the widespread use of EVs and their large-scale integration into the energy system will present several operational and technological hurdles. In the energy industry, an innovative solution known as the EVs smart parking lot (SPL) is introduced to handle EV charging and discharging electricity and energy supply challenges. This paper investigates social equity access and mobile charging stations (MCSs) for EVs, where the owner of MCSs is the EV parking lot. Accordingly, a new self-scheduling model for SPLs is presented in this paper that incorporates scheduling of the MCSs as temporary charging infrastructures while considering social equity access and optimizes SPL energy generation and storage schedule. The main objectives of this research are to (i) develop MCSs accessibility measures and quantify the equity impacts of MCSs locations by modeling prioritized demand based on several indices; (ii) determine the optimal set-points of SPL components (i.e., combined heat and power (CHP), photovoltaic system, electrical and heat-energy storage, and MCSs) to manage electrical peak demand and to maximize the economic benefits of SPLs. Results indicate that the proposed demand prioritization function model can meet the required EV charging demands for prioritized events, and the self-scheduling model for SPLs satisfies the charging demand of the EVs in the SPL location. Also, the social equity access to the EV charging stations is satisfied by analyzing the operation of MCSs around the prioritized demand of the prioritized events and social equity access indices.
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Vehicle electrification, automation, and shared mobility – also referred to as the transportation three revolutions (3Rs) – are the emerging trends in future mobility. This study performed a comprehensive integrated analysis to investigate the potential future development of passenger transportation in the United States. A technical-economic mobility model, a chemical transport model, and a health impact assessment tool were utilized. This study first adopted several assumptions for vehicle sales under the impact of the 3Rs, and made projections to 2050 for vehicle stocks, distance travel, energy use, and carbon dioxide (CO2) emissions. This study then quantified the impacts of changing emissions on concentrations of fine particulate matter and associated health benefits. Compared to a projected 2050 business-as-usual case, the wide use of electrification could lead to reductions of ~50% in petroleum consumption and ~75% in CO2 emissions, and obtain health benefits of 5500 prevented premature deaths, corresponding to $58 billion annually. The net energy impacts of automation are highly uncertain, and the improved efficiency from automation might be offset by an increase in travel. Sharing would bring additional benefits. The combination of the 3Rs could maximize the energy savings, carbon mitigations, and health benefits. The results of this study suggest that policies/incentives are needed to promote the transition from single-occupied conventional vehicles to shared electric vehicles.
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This study introduces an integrated modeling framework to evaluate long-term national corridor charging infrastructure requirements in the United States to support the growing inter-city charging demand with the rapid growth in the battery electric vehicle (BEV) market. The core model is an optimization model that considers spatial and temporal dimensions and models heterogeneous behaviors between travelers. The model also introduces the travelers’ inconvenience cost function by linking travelers’ acceptance of the charging infrastructure with exogenous technology and social factors. The inconvenience cost function simulates mode choice between BEVs and alternative modes by heterogenous travelers. We applied the framework to assess the inter-regional charging infrastructure requirements for the entire U.S. mainland interstate highway network. We evaluated impacts on the infrastructure design and its public acceptance with changes in policy, technology, and demographic characteristics, and we also quantified the importance of modeling full-scale inter-regional charging infrastructure requirements compared to the conventional regional level analyses.
Chapter
Transportation equity is a way to frame distributive justice concerns in relation to how social, economic, and government institutions shape the distribution of transportation benefits and burdens in society. It focuses on the evaluative standards used to judge the differential impacts of policies and plans, asking who benefits from and is burdened by them and to what extent. Questions of transportation equity involve both sufficientarian and egalitarian concerns with both absolute levels of wellbeing, transport-related poverty and social exclusion as well as with relative levels of transport-related inequalities. Ultimately, the study of transport equity explores the multiple channels through which transport and land use policies can create conditions for more inclusive cities and transport systems that allow different people to flourish, to satisfy their basic needs and lead a meaningful life. Transportation equity issues broadly encompass how policy decisions shape societal levels of environmental externalities and what groups are more or less exposed to them, as well as how those decisions affect the lives of different groups in terms of their ability to access life-enhancing opportunities such as employment, healthcare and education. Equity is a crucial part of a broader concern with transport and mobility justice. The call for transport justice goes beyond distributive concerns, and yet justice cannot be achieved without equity.
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Access terminology is evolving since its inception by Hansen in 1959. Accounting accessibility is central to multiple disciplines such as geography, transportation, health, economics, social sciences, etc. Developing indicators to measure access is a common practice and usually favor specific dimensions of access based on application. Although measuring accessibility and developing related indicators is a common practice, there are missing links in the indicator development, planning process, its implementation and related policy-making. Due to many available indicators, each differing in context, the practicality of implementation and their transferability is generally lost. Current work focuses on extracting commonalities between indicators and understanding how the contextual focus of indicators’ have changed over time to measure access. Requirements for improved access related policies, developing realistic measures and future research directions based on gaps in the identified access measures are suggested.
Article
The cost to charge an electric vehicle (EV) varies depending on the price of electricity at different charging sites (home, workplace, public), vehicle use, region, and time of day, and for different charging power levels and equipment and installation costs. This paper provides a detailed assessment of the current (2019) levelized cost of light-duty EV charging in the United States, considering the purchase and installation costs of charging equipment and electricity prices from real-world utility tariffs. We find national averages of 0.15/kWhforbatteryEVsand0.15/kWh for battery EVs and 0.14/kWh for plug-in hybrid EVs in the United States. Costs, however, vary considerably (e.g., 0.08/kWhto0.08/kWh to 0.27/kWh for battery EVs) for different charging behaviors and equipment costs, corresponding to a total projected fuel cost savings between 3,000and3,000 and 10,500 compared with gasoline vehicles (over a 15-year time horizon). Regional heterogeneities and uncertainty on lifetime vehicle use and future fuel prices produce even greater variations.
Article
The successful market entry of plug-in electric vehicles (PEVs) is contingent on them being adopted by consumers, the first of which will be early adopters. The current understanding of these early adopters is based on small samples of PEV buyers gathered at one point in time. Here we present multi-year (2012–2017) questionnaire survey data on the socio-demographic profile of 11,037 PEV adopters in California. Latent class cluster analysis reveals four heterogeneous groups of PEV buyers. 49% are High income families, 26% Mid/high income old families, 20% Mid/high income young families, and about 5% are Middle income renters. Using the latent classes as input factors in Bass diffusion models we show that high income families may not continue to be the largest group of PEV adopters, while high income families are 49% of the PEV market today, they only represent 3.6% of California households. For market growth to continue the mid/high- and middle-income clusters need to begin adopting PEVs in greater numbers than they are doing today. Policymakers will need to consider the different needs these consumers have for infrastructure and incentives compared to high income families.
Article
The collection of big data, as an alternative to traditional resource-intensive manual data collection approaches, has become significantly more feasible over the past decade. The availability of such data, coupled with more sophisticated predictive statistical techniques, has contributed to an increase in attention towards the application of these data, particularly for transportation analysis. Within the transportation literature, there is a growing emphasis on developing sources of commonly collected public transportation data into more powerful analytical tools. A commonly held belief is that application of big data to transportation problems will yield new insights previously unattainable through traditional transportation data sets. However, there exist many ambiguities related to what constitutes big data, the ethical implications of big data collection and application, and how to best utilize the emerging data sets. The existing literature exploring big data provides no clear and consistent definition. While the collection of big data has grown and its application in both research and practice continues to expand, there is a significant disparity between methods of analysis applied to such data. This paper summarizes the recent literature on sources of big data and commonly applied methods used in its application to public transportation problems. We assess predominant big data sources, most frequently studied topics, and methodologies employed. The literature suggests smart card and automated data are the two big data sources most frequently used by researchers to conduct public transit analyses. The studies reviewed indicate that big data has largely been used to understand transit users’ travel behavior and to assess public transit service quality. The techniques reported in the literature largely mirror those used with smaller data sets. The application of more advanced statistical methods, commonly associated with big data, has been limited to a small number of studies. In order to fully capture the value of big data, new approaches to analysis will be necessary.
Article
This paper provides the first empirical analysis of the homeowner-renter gap for electric vehicles. Using newly-available U.S. nationally representative data, the analysis shows that homeowners are three times more likely than renters to own an electric vehicle. The gap is highly statistically significant, and remains even after controlling for income. For example, among households with annual income between 75,000and75,000 and 100,000, 1 in 130 homeowners owns an electric vehicle, compared to 1 in 370 renters. Additional controls do little to narrow the gap. The paper argues that this is a version of what economists have called the “landlord-tenant’’ problem, and briefly discusses potential policy implications.
Book
For the first time in half a century, real transformative innovations are coming to our world of passenger transportation. The convergence of new shared mobility services with automated and electric vehicles promises to significantly reshape our lives and communities for the better—or for the worse. The dream scenario could bring huge public and private benefits, including more transportation choices, greater affordability and accessibility, and healthier, more livable cities, along with reduced greenhouse gas emissions. The nightmare scenario could bring more urban sprawl, energy use, greenhouse gas emissions, and unhealthy cities and individuals. In Three Revolutions, transportation expert Dan Sperling, along with seven other leaders in the field, share research–based insights on potential public benefits and impacts of the three transportation revolutions. They describe innovative ideas and partnerships, and explore the role government policy can play in steering the new transportation paradigm toward the public interest—toward our dream scenario of social equity, environmental sustainability, and urban livability. Many factors will influence these revolutions—including the willingness of travelers to share rides and eschew car ownership; continuing reductions in battery, fuel cell, and automation costs; and the adaptiveness of companies. But one of the most important factors is policy. Three Revolutions offers policy recommendations and provides insight and knowledge that could lead to wiser choices by all. With this book, Sperling and his collaborators hope to steer these revolutions toward the public interest and a better quality of life for everyone.
Article
Electric vehicles are considered as one of the most effective technologies for reducing current greenhouse gas emissions from the transport sector. Although in many countries, local and national governments have introduced incentives and subsidies to facilitate the electric vehicle market penetration, in Sweden, such benefits have been limited. Results from a survey carried out among private owners of electric vehicles are presented in this paper, including the analysis of the respondents socio-demographic characteristics, reasons for choosing an electric vehicle, charging locations and driving preferences, among others. The main results characterize current electric vehicle drivers as male, well-educated, with medium-high income; electric vehicles are used mainly for private purposes and charged at home during night time. Furthermore, the paper presents an analysis of the impact of large-scale penetration of electric vehicles on existing power distribution systems. The findings presented in this paper provide important insights for assuring a sustainable large-scale penetration of electric vehicles by learning from the experiences of early adopters of the technology and by analyzing the impact of different EV penetration scenarios on the power distribution grid.