Zero Emission Vehicles

This report is available at no cost from the National Renewable Energy Laboratory (NREL) at www.nrel.gov/publications. U.S. Department of Energy (DOE) reports produced after 1991 and a growing number of pre-1991 documents are available free via www.OSTI.gov. Cover photo from iStock 1184915589. NREL prints on paper that contains recycled content.

The transition to sustainable transportation is a critical challenge for Small Island Developing States (SIDS), which face unique constraints related to energy resources, high fuel costs, and climate change vulnerability. While battery electric buses (BEBs) are increasingly seen as a viable solution, research comparing their operational and economic performance with diesel and compressed natural gas (CNG) buses in SIDS remains scarce. This study addresses this gap by employing a novel methodology that integrates real-world telematics data from a pilot fleet of diesel and CNG buses with a comprehensive cost-benefit analysis (CBA) in a Caribbean SIDS. The analysis reveals that approximately 80% of daily routes are within the range of a representative BEB, supporting overnight depot charging as a feasible strategy. However, route-specific assessments suggest that certain high-demand routes may require opportunity charging to ensure operational efficiency. The financial modelling under various fuel and electricity price scenarios demonstrates significant cost savings for BEBs over their operational lifespan, with competitive payback periods that justify the higher initial investment. Furthermore, BEBs show a substantial reduction in greenhouse gas emissions compared to diesel and CNG alternatives, reinforcing their environmental benefits. These findings provide valuable, data-driven insights for SIDS policymakers and transportation planners, highlighting the viability of BEBs as a cost-effective and environmentally sustainable alternative for public transportation systems in resource-constrained environments.

Developing more sustainable public transportation modes has become one of the key elements for mitigating the energy and environmental issues that are related to the global transportation sector, especially high capacity public transportation modes such as bus and subway systems. In this study, the expected environmental implications of Fuel Cell Electric Buses (FCEBs) in Australia during the next 25 years were determined. For this purpose, ARIMA and Exponential Smoothing models were developed to predict the expected GHG emissions and the annual kilometres that will be travelled by buses in 2050. The expected Greenhouse Gas (GHG) emissions produced by buses were determined, based on different scenarios (0% FCEBs penetration, 50% FCEBs penetration, 100% FCEBs penetration). The results of the study concluded that a slight increase in the annual travelled distance by buses in Australia is expected over the next 25 years, with a total increase of 6.9% during the period 2022-2050. Moreover, over time, the environmental implications of FCEBs will become more significant, due to the acceleration in the development of more eco-friendly hydrogen production methods, which could lead to a substantial decrease of up to 89% in GHG emissions, with a 100% transition to FCEBs by 2050 compared to 2022.

This paper presents a twofold modelling exercise to investigate the implementation of battery electric buses (BEBs) in a full transit network. First, using three BEB concepts: flash, opportunity, and overnight, a real-time simulation model is developed for a full transit BEBs operation in order to (1) quantify the energy demands, (2) design the required infrastructure of the charging station, (3) test the transit operation feasibility, and (4) generate the charging load profile. Simulation results show that flash and opportunity BEBs are more feasible for full transit BEBs operation, however they suffer from high and intermittent power demands. Second, the generated charging load profile for each BEB operation is utilized to study its impact on the utilization and lifetime of the transformers, and the operation of the local distribution grid. Results indicate that the operation of overnight electric buses is more feasible as it relates to their impacts on the substation transformer and distribution feeders overloading, voltage regulation and quality aspects, and operation of voltage control devices. Collectively, findings from this study highlight that the selection of BEBs in a full network transit operation hinges on achieving feasible operation while reducing impacts on utility grid. Insights derived from this work can help optimize the implementation of BEBs in transit context.

Public transport services, particularly bus services, play an important role in a sustainable transportation system. However, despite various efforts, bus ridership has decreased. The appearance of shared and on-demand vehicle services is one of the main reasons for this issue. In addition, bus tourism services have been successfully developed to meet the exigent needs of tourists. Therefore, a new level of daily bus service is necessary to adapt to the changing demands of customers. Bus interaction (BI) plays an important role in bus services. Nevertheless, the conventional concept of BI mainly refers to users, physical interaction, and safety, but it does not address non-users, non-physical interactions, service quality, and other aspects. This study aims to elaborate on a new concept of bus services. Based on this, we developed a theoretical framework for BI. A meta-analysis was then conducted to identify the achievements and untouched aspects. The results of this study provide three main contributions. First, an unprecedented novel concept of BI is defined, including 13 types of interactions. Second, a comprehensive theoretical framework of BI is established based on the relationships between eight sustainable bus system sub-aspects and 13 BI types. Third, based on the theoretical framework and findings of the reviewed studies, a common finding comprehensive framework of BI is completed, which is accompanied by 1) key findings of the 13 BI types, 2) conclusions of traffic conditions affecting BI research, 3) BI research gaps, and 4) 16 main suggestions for future BI research.

This report evaluates the market status and potential freight market penetration of zero emission vehicles (ZEVs) and near ZEVs in the medium and heavy duty class within the California market. It evaluates alternative technologies, primarily battery electric, fuel cell, and hybrid technologies, and compares them to existing gasoline, diesel, and natural gas vehicles used in comparable applications. Refueling infrastructure requirements and logistics planning are considered along with vehicle technology. The report’s primary focus is on intra-urban, as opposed to long haul, deployment scenarios. Intra-urban scenarios produce the greatest potential for reduction of pollutant exposure while minimizing problems associated with the reduced range of some developing vehicle technologies. In California, there are currently 2080 hybrid, 300 medium duty and 40 heavy duty electric vehicles in demonstration or revenue service. There are currently plans to deploy several dozen heavy duty fuel ce...

Author(s): Ioannou, Petros; Giuliano, Genevieve; Dessouky, Maged; Chen, Pengfei; Dexter, Sue | Abstract: The current freight transportation network is highly unbalanced as routing decisions are made by individual users without coordination. Certain routes may become congested when chosen based on current traffic information without any anticipation that if other users do the same, these routes are no longer the best. This project developed a centrally coordinated load balancing system that considers all user demands and generates individual routes that balance freight loads across the network by minimizing cost. It is initially assumed that all vehicles are diesel and then gradually increases zero emissions vehicles such as electric trucks for a mixed fleet of trucks. The electric trucks add additional constraints due to limitation of range and charging time of batteries. As the number of electric trucks increases, the emissions reduce as expected; however, the cost of charging does...

Author(s): Ioannou, Petros; Giuliano, Genevieve; Dessouky, Maged; Chen, Pengfei; Dexter, Sue | Abstract: The current freight transportation network is highly unbalanced as routing decisions are made by individual users without coordination. Certain routes may become congested when chosen based on current traffic information without any anticipation that if other users do the same, these routes are no longer the best. This project developed a centrally coordinated load balancing system that considers all user demands and generates individual routes that balance freight loads across the network by minimizing cost. It is initially assumed that all vehicles are diesel and then gradually increases zero emissions vehicles such as electric trucks for a mixed fleet of trucks. The electric trucks add additional constraints due to limitation of range and charging time of batteries. As the number of electric trucks increases, the emissions reduce as expected; however, the cost of charging does...

Although many municipalities have climate action plans with targets and goals, effective climate action still faces significant implementation gaps. Implementation can falter due to barriers for the deployment of low-carbon solutions, as well as the lack of cultural, systemic, and psychological support for such solutions. Cultural drivers and perceptions shape citizens' behaviors and can perpetuate carbon-intensive lifestyles. This paper focuses on measures in climate action planning in the Metro Vancouver region of Canada regarding transportation, which remains the largest single source of greenhouse gas emissions and has a low chance of reaching its emissions-reductions targets. Shifting towards greater sustainability will entail a challenge of transformative change, involving shifts in systems, behaviors, worldviews, and cultures. In implementation, the full complexity of the climate action challenge becomes most evident. A scoping review of climate action documentation and semi-structured interviews are used to examine (1) barriers to effective implementation, (2) socio-cultural perceptions and approaches to public engagement and (3) novel areas for transformational action. The study found a need to reweight the focus of climate action, which is predominantly set on techno-managerial efforts, also to include communication, narratives and broader systems change, which are the key barriers to low-carbon urban mobility.

In the transportation sector, electric battery bus (EBB) deployment is considered to be a potential solution to reduce global warming because no greenhouse gas (GHG) emissions are directly produced by EBBs. In addition to the required charging infrastructure, estimating the energy consumption of buses has become a crucial precondition for the deployment and planning of electric bus fleets. Policy and decision-makers may not have the specific tools needed to estimate the energy consumption of a particular bus network. Therefore, many state-of-the-art studies have proposed models to determine the energy demand of electric buses. However, these studies have not critically reviewed, classified and discussed the challenges of the approaches that are applied to estimate EBBs’ energy demands. Thus, this manuscript provides a detailed review of the forecasting models used to estimate the energy consumption of EBBs. Furthermore, this work fills the gap by classifying the models for estimatin...

A large-scale adoption of electric buses (EBs) is a promising solution to mitigate greenhouse gas emissions from the transportation sector. In the upcoming decades, the development of EB technologies will be initiated worldwide, including in Malaysia. Government policies to support EB deployments have been widely established. Therefore, Malaysia’s National Automotive Policy has stated a roadmap of policies to promote a national groundwork accordingly. Following the elaboration of Malaysia’s goals for EBs deployments by 2014 and 2020, there are crucial associated topics for EBs implementation, including EB innovations and technologies adoption. This study presents a deep discussion about the groundwork of EB innovations that have been initiated in Malaysia to meet the roadmap targets. This paper also comprehensively reviews the technical specifications of EB innovation technologies, including Electric Bus Innovation Malaysia, Malaysia Automotive Institute, and Go Auto prototypes. In ...

Low-emission alternative bus technologies are of increasing interest to bus fleet operators due to the reduced environmental impact and potential for lower operating costs. However, with uncertainty regarding the total cost of ownership of new technologies and life cycle impacts beyond the typical well-to-wheel boundary, stakeholders may not have the necessary specific tools or evidence to evaluate life cycle impacts. The aim of this paper is to develop a novel framework to assist decision-makers in assessing the uncertainty of the life cycle impacts of alternative bus technologies. The Technology Impact Forecasting methodology was employed, integrating a life cycle model, to investigate whole life cycle impacts in an exploratory assessment environment, allowing for the analysis and trade-off evaluations of alternative drivetrain technologies and operational scenarios. This research provides a comprehensive novel framework for addressing uncertainty in whole life cycle costs and GHG emissions for the manufacture, use, maintenance and infrastructure phases of diesel and battery electric buses. Eleven scenarios are assessed in the framework, evaluating combinations of battery technologies, well-to-tank pathways, charging infrastructure and auxiliary demands. For every battery electric bus scenario, there is an 80% confidence that life cycle GHG emissions are mitigated by 10% to 58% compared to the baseline diesel bus, but life cycle costs are 129% to 247% higher. Opportunity charged electric buses employing a lithium-titanate battery are the most effective scenario for mitigating GHG emissions per additional cost of the new technology to the operator. The framework highlights a key trade-off between dependence on battery capacity and high-power charging infrastructure for battery electric bus technologies. The framework enables stakeholders to make technology adoption and resource allocation decisions based on the risk of a scenario and provides a level of confidence in a technologies' ability to mitigate whole life cycle impacts.

This report could not have been completed without the assistance of numerous individuals during this comprehensive review of California's Innovative Clean Transit regulation. The authors would like to extend our most sincere thanks to the project team from California Air Resources Board-especially Yachun Chow, Jing Guo, Bo Yang, Shirin Barfjani, and Annmarie Rodgersfor continuous leadership, support, and guidance throughout the project and for numerous thorough reviews of this report. Additional thanks go to contributors from the National Renewable Energy Laboratory (NREL), including Leslie Eudy (formerly of NREL) for initiating this effort and laying all the groundwork that would become the basis for this comprehensive review, and Alex Schroeder for providing valuable project management and technical guidance. Additional contributions were made by the University of California, Berkeley's Zachary Wu and Emily Rogers, who supported our interviews with zero-emission bus (ZEB) industry stakeholders and provided additional analysis and literature review. We also greatly appreciate the input from numerous stakeholders in the ZEB industry-including transit agencies, bus manufacturers, technology providers, electric utilities, and fuel suppliers-for participating in interviews and providing valuable information to the authors for this report. Finally, a big thank you goes to the California Transit Association, especially Michael Pimentel, and its ZEB Task Force members for providing input on the direction of the comprehensive review and ensuring California transit agency perspectives are well represented.

Transportation systems play a critical role in economic development and social connectivity. However, they are also significant contributors to greenhouse gas emissions and environmental degradation. To achieve sustainable development goals, there is a growing need to harness the principles of physics and geography to design and implement sustainable transportation systems. This paper examines the interplay between physics, geography, and sustainable transportation, highlighting the application of physics principles in energy-efficient technologies, the influence of geography on transportation patterns, and the importance of sustainable transportation planning. By integrating physics and geography, we can develop innovative solutions that reduce emissions, enhance energy efficiency, and improve urban sustainability.

The electrification of transportation sector represents a promising approach to reduce transit-related greenhouse gas emissions. However, both transportation and power utility sectors retain various challenges in facilitating the seamless integration of battery electric bus (BEB) fleet systems. Among those challenges, the lack of appropriate simulation tools to model, design, and optimize BEB fleet systems is the most salient. Accordingly, this paper proposes a new mathematical formulation to model BEB fleet systems. The model considers the operational requirements of public bus transit systems and the energy consumption characteristics of BEBs. The proposed transit model is then integrated with the power distribution system model to develop an integrated utility-transit problem formulation for the optimal design of BEB systems. The formulated optimization problem aims at determining the optimal configuration parameters of BEB fleet systems that include the bus battery capacity, chargers rated power, and the total number of installed chargers in the charging station. The developed utility-transit model is formulated as a mixed integer nonlinear programming problem (MINLP) and is solved using the Basic Open-Source Nonlinear Mixed INteger Programming (BON-MIN) optimization solver. Real-world transit system data are used to validate the efficacy of the proposed integrated utility-transit model. The simulation results indicate that consideration of both power distribution and transit networks operation requirements significantly impact the choice of the BEBs configuration. Index Terms-Battery electric bus (BEB), charging schedule, electric bus transit networks, on-route charging, power distribution systems (PDS). NOMENCLATURE A. Indices b, r Indices for transit network buses/routes. a, j Indices for bus' assignments/trips. t, d Indices for time steps. i Indices for nodes/branches in power distribution system (PDS). B. Sets B, R, A Set of transit network buses, routes and assignments, respectively.

Diesel-powered, human-driven buses currently dominate public transit options in most U.S. cities, yet they produce health, environmental, and cost concerns. Emerging technologies may improve fleet operations by cost-effectively reducing emissions. This study analyzes both battery-electric buses and self-driving (autonomous) buses from both cost and qualitative perspectives, using the Capital Metropolitan Transportation Authority’s bus fleet in Austin, Texas. The study predicts battery-electric buses, including the required charging infrastructure, will become lifecycle cost-competitive in or before the year 2030 at existing U.S. fuel prices ($2.00/gallon), with the specific year depending on the actual rate of cost decline and the diesel bus purchase prices. Rising diesel prices would result in immediate cost savings before reaching $3.30 per gallon. Self-driving buses will reduce or eliminate the need for human drivers, one of the highest current operating costs of transit agencies...

This paper presents a twofold modelling exercise to investigate the implementation of battery electric buses (BEBs) in a full transit network. First, using three BEB concepts: flash, opportunity, and overnight, a real-time simulation model is developed for a full transit BEBs operation in order to (1) quantify the energy demands, (2) design the required infrastructure of the charging station, (3) test the transit operation feasibility, and (4) generate the charging load profile. Simulation results show that flash and opportunity BEBs are more feasible for full transit BEBs operation, however they suffer from high and intermittent power demands. Second, the generated charging load profile for each BEB operation is utilized to study its impact on the utilization and lifetime of the transformers, and the operation of the local distribution grid. Results indicate that the operation of overnight electric buses is more feasible as it relates to their impacts on the substation transformer and distribution feeders overloading, voltage regulation and quality aspects, and operation of voltage control devices. Collectively, findings from this study highlight that the selection of BEBs in a full network transit operation hinges on achieving feasible operation while reducing impacts on utility grid. Insights derived from this work can help optimize the implementation of BEBs in transit context.

The TransitCenter Equity Dashboard tracks how well public transit systems in seven densely populated urban regions in the United States serve their riders and how changes to transit service affect riders over space, time, and cost constraints. The dashboard presents a series of charts and interactive maps that can be used to evaluate variations in transit accessibility and equity. It was created using publicly available data and primarily open-source software. All measures can be accessed by users seeking to conduct their own analyses. Results demonstrate differences in agency responses to COVID-19 as well as baseline transit service levels provided to different demographic groups.

This volume reports the first results of the Observatory on the Transformations of the Italian Automotive Ecosystem. The main focus is on the consequences of the technology acceleration following the European legislation that has decreed the end of the sales of the production of endothermic motors in 2035. The Observatory was founded by CAMI - Department of Management of Ca' Foscari University of Venice and Motus-E, the association of industrial operators that promote electric vehicles. It seeks to identify the key variables to assess whether and to what extent the current technological development is shaping the evolution of the automotive ecosystem, and ultimately whether it represents an opportunity or a threat for incumbents. The main objective of the Observatory is to produce and identify scientific evidence on the ecosystem of mobility to be made available to economic, entrepreneurial, political-institutional and scientific networks. The Observatory is based on a database composed of companies belonging to the industrial chain of road mobility (supply chain for cars, motorcycles, micro-mobility, buses, trucks, as well as companies providing engineering services, components and after-market services and infrastructure for electric and similar refuelling and charging). The technological evolution of recent years is affecting the drive-train of vehicles, which will be subject to radical changes starting from the abandonment of internal combustion engine technology. In this scenario it is no longer enough to continue analysing the ‘traditional supply chain’, but a broader analysis is needed that takes into account the entire mobility ecosystem. Electric mobility is, to date, the most mature technology to replace the endothermic engine and will involve: a radical change in the technological base; an expansion of the boundaries of the automotive supply chain involving those of digitalisation and services; the need for complementary asset development.

The electrification of transportation sector represents a promising approach to reduce transit-related greenhouse gas emissions. However, both transportation and power utility sectors retain various challenges in facilitating the seamless integration of battery electric bus (BEB) fleet systems. Among those challenges, the lack of appropriate simulation tools to model, design, and optimize BEB fleet systems is the most salient. Accordingly, this paper proposes a new mathematical formulation to model BEB fleet systems. The model considers the operational requirements of public bus transit systems and the energy consumption characteristics of BEBs. The proposed transit model is then integrated with the power distribution system model to develop an integrated utility-transit problem formulation for the optimal design of BEB systems. The formulated optimization problem aims at determining the optimal configuration parameters of BEB fleet systems that include the bus battery capacity, chargers rated power, and the total number of installed chargers in the charging station. The developed utility-transit model is formulated as a mixed integer nonlinear programming problem (MINLP) and is solved using the Basic Open-Source Nonlinear Mixed INteger Programming (BON-MIN) optimization solver. Real-world transit system data are used to validate the efficacy of the proposed integrated utility-transit model. The simulation results indicate that consideration of both power distribution and transit networks operation requirements significantly impact the choice of the BEBs configuration. Index Terms-Battery electric bus (BEB), charging schedule, electric bus transit networks, on-route charging, power distribution systems (PDS). NOMENCLATURE A. Indices b, r Indices for transit network buses/routes. a, j Indices for bus' assignments/trips. t, d Indices for time steps. i Indices for nodes/branches in power distribution system (PDS). B. Sets B, R, A Set of transit network buses, routes and assignments, respectively.

This study investigates the impacts of vehicular, operational, topological, and external parameters on the energy consumption (EC) of battery-electric buses (BEBs) in transit operation. Furthermore, the study develops a data-driven prediction model for BEB energy consumption in transit operation that considers these four parameters. A Simulink energy model is developed to estimate the EC rates and validated using the Altoona’s test real-world data. A full-factorial experiment is used to generate 907,199 scenarios for BEB operation informed by 120 real-world drive cycles. A multivariate multiple regression model was developed to predict BEB’s EC. The regression model explained more than 96% of the variation in the EC of the BEBs. The results show the significant impacts of road grade, the initial state of charge, road condition, passenger loading, driver aggressiveness, average speed, HVAC, and stop density on BEB’s energy consumption, each with a different magnitude. The study concl...

The electrification of transportation sector represents a promising approach to reduce transit-related greenhouse gas emissions. However, both transportation and power utility sectors retain various challenges in facilitating the seamless integration of battery electric bus (BEB) fleet systems. Among those challenges, the lack of appropriate simulation tools to model, design, and optimize BEB fleet systems is the most salient. Accordingly, this paper proposes a new mathematical formulation to model BEB fleet systems. The model considers the operational requirements of public bus transit systems and the energy consumption characteristics of BEBs. The proposed transit model is then integrated with the power distribution system model to develop an integrated utility-transit problem formulation for the optimal design of BEB systems. The formulated optimization problem aims at determining the optimal configuration parameters of BEB fleet systems that include the bus battery capacity, chargers rated power, and the total number of installed chargers in the charging station. The developed utility-transit model is formulated as a mixed integer nonlinear programming problem (MINLP) and is solved using the Basic Open-Source Nonlinear Mixed INteger Programming (BON-MIN) optimization solver. Real-world transit system data are used to validate the efficacy of the proposed integrated utility-transit model. The simulation results indicate that consideration of both power distribution and transit networks operation requirements significantly impact the choice of the BEBs configuration. Index Terms-Battery electric bus (BEB), charging schedule, electric bus transit networks, on-route charging, power distribution systems (PDS). NOMENCLATURE A. Indices b, r Indices for transit network buses/routes. a, j Indices for bus' assignments/trips. t, d Indices for time steps. i Indices for nodes/branches in power distribution system (PDS). B. Sets B, R, A Set of transit network buses, routes and assignments, respectively.

This paper presents a twofold modelling exercise to investigate the implementation of battery electric buses (BEBs) in a full transit network. First, using three BEB concepts: flash, opportunity, and overnight, a real-time simulation model is developed for a full transit BEBs operation in order to (1) quantify the energy demands, (2) design the required infrastructure of the charging station, (3) test the transit operation feasibility, and (4) generate the charging load profile. Simulation results show that flash and opportunity BEBs are more feasible for full transit BEBs operation, however they suffer from high and intermittent power demands. Second, the generated charging load profile for each BEB operation is utilized to study its impact on the utilization and lifetime of the transformers, and the operation of the local distribution grid. Results indicate that the operation of overnight electric buses is more feasible as it relates to their impacts on the substation transformer and distribution feeders overloading, voltage regulation and quality aspects, and operation of voltage control devices. Collectively, findings from this study highlight that the selection of BEBs in a full network transit operation hinges on achieving feasible operation while reducing impacts on utility grid. Insights derived from this work can help optimize the implementation of BEBs in transit context.

The transport sector in Latin America accounts for over one-third of CO2 emissions. Shifting passengers from private vehicles to high capacity public transit has been identified as critical to relieve congestion and decarbonize transport, and switching to cleaner bus technologies can provide additional benefits in mitigating greenhouse gas emissions while reducing noise and air pollution. The uptake of clean bus technologies in Latin America and the Caribbean is slower than in China, Europe, and the U.S.A. This paper focuses on deepening understanding of the financial barriers to adopting clean bus technologies by developing a cost-effectiveness analysis that (i) assesses the marginal cost of reducing an additional ton of CO2 when switching from diesel buses to clean bus options and (ii) identifies the main drivers that determine this cost. The methodology has been applied to Santiago, the capital city of Chile, and results show that, given the current context, compressed natural ga...

In the transportation sector, electric battery bus (EBB) deployment is considered to be a potential solution to reduce global warming because no greenhouse gas (GHG) emissions are directly produced by EBBs. In addition to the required charging infrastructure, estimating the energy consumption of buses has become a crucial precondition for the deployment and planning of electric bus fleets. Policy and decision-makers may not have the specific tools needed to estimate the energy consumption of a particular bus network. Therefore, many state-of-the-art studies have proposed models to determine the energy demand of electric buses. However, these studies have not critically reviewed, classified and discussed the challenges of the approaches that are applied to estimate EBBs’ energy demands. Thus, this manuscript provides a detailed review of the forecasting models used to estimate the energy consumption of EBBs. Furthermore, this work fills the gap by classifying the models for estimatin...

To improve the air quality in urban areas, diesel buses are getting replaced by battery electric buses (BEBs). This conversion introduces several challenges, such as the proper control of the charging process and a reduction in the operational costs, which can be addressed by introducing smart charging concepts for BEB fleets. Therefore, this paper proposes a real-time scheduling and optimization (RTSO) algorithm for the charging of multiple BEBs in a depot. The algorithm assigns a variable charging current to the different time slots the charging process of each BEB is divided to provide an optimal charging schedule that minimizes the charging cost, while satisfying the power limitations of the distribution network and maintaining the operation schedule of the BEBs. A genetic algorithm is used to solve the formulated cost function in real time. Several charging scenarios are tested in simulation, which show that a reduction in the charging cost up to 10% can be obtained under a dyn...

This study deals with the design and the evaluation of technological solutions for the electrification of public transport in urban areas. A Decision Support System (DSS) developed by ENEA † within the Research program on Electric System (RSE) has been adopted in order to verify the technical feasibility of several electric architectures of single bus lines and compare the investment and management costs, as well as the external costs due to vehicle emissions and noises, of the feasible solutions with respect to the conventional alternatives (Compressed Natural Gas, CNG, and diesel). The DSS has been applied to several bus lines located in the southwest area of the city of Rome, Italy, and covering different types of service: peripheral lines, main lines connecting suburbs with the city center and secondary lines going to the main metro stations. Input data for the DSS derived both by simulation and by open database available from the public transport operator in Rome (ATAC). Results show that a suitable electric architecture can be found for each of these lines with lower or comparable total costs with respect to the traditional alternatives. Finally, a sensitivity analysis has been performed considering several scenarios in terms of discount rate of recharge stations and batteries, battery's duration, price of conventional fuels.

The growing consumption of fossil fuels and its negative environmental consequences have been a major concern during the last few decades. In line with that, public transport operators face global pressure to replace diesel buses by battery-electric buses (BEBs) in many countries. However, BEBs need to be recharged several times throughout the day to avoid running out of energy due to their limited driving range and slow charging rate. Accordingly, operating BEBs is substantially more sensitive to unanticipated delays and excess energy consumption, which raises serious challenges with respect to charging schedules. Moreover, BEBs are only a truly sustainable alternative if they are powered by renewable energy generators (REGs), which have intermittent and uncertain generation. Thus, we design and propose a real-time decision support system to overcome these uncertainties and maximize the utilization of REGs and minimize the impact on the grid while guaranteeing a feasible operation ...

The penetration of e-mobility is growing thanks to the European guidelines on climate preservation regarding the reduction in CO2 emission. Governments are adapting their economic policies with the aim to incentivize e-mobility. At the same time, with a view to equality and accessibility, countries are working to introduce e-mobility services also for people with disabilities in order to improve the quality of their lives. The paper reports the deployment of an e-mobility service for persons with disabilities carried out in a project financed by Sapienza University of Rome. The project includes a feasibility study and a cost–benefit analysis in order to identify the optimal solution from a technical and environmental point of view for a sustainable e-mobility service for people with reduced mobility. A methodology to design a service based on optimal routes and electric vehicles with respect to energy consumption, time travel, energy and vehicle costs and quality of service is propo...

The Guangdong-Hong Kong-Macau Greater Bay Area (GD-HK-MO) also referred as Greater Bay Area (GBA), is a megalopolis, consisting of nine cities and two special administrative regions, i.e., Hong Kong and Macao in South China. GBA has a total population of approximately 71.2 million people representing about 5% of China’s total population with a combined regional GDP at USD 1642 billion in 2018, i.e. about 12% of GDP for the whole mainland China. Hong Kong acting as a window of China, plays a critical role in contributing to the growth of the GDP. Given the enormous scale of this regional economy and increasing collaboration among these GBA cities, it is utmost important to design a novel environmental impact assessment and emission measurements of the cross-border transportation among Hong Kong and various GBA cities with the aim of proposing countermeasures on carbon emissions of vehicles in the transport and logistics sector of the GBA. In the study, two modified gravity models are...

The Guangdong-Hong Kong-Macau Greater Bay Area (GD-HK-MO) also referred as Greater Bay Area (GBA), is a megalopolis, consisting of nine cities and two special administrative regions, i.e., Hong Kong and Macao in South China. GBA has a total population of approximately 71.2 million people representing about 5% of China’s total population with a combined regional GDP at USD 1642 billion in 2018, i.e. about 12% of GDP for the whole mainland China. Hong Kong acting as a window of China, plays a critical role in contributing to the growth of the GDP. Given the enormous scale of this regional economy and increasing collaboration among these GBA cities, it is utmost important to design a novel environmental impact assessment and emission measurements of the cross-border transportation among Hong Kong and various GBA cities with the aim of proposing countermeasures on carbon emissions of vehicles in the transport and logistics sector of the GBA. In the study, two modified gravity models are...

The Guidebook is a ready reckoner for transit agencies to help them adopt a calibrated approach to induct electric buses in their services. This is to ensure that the technology shift neither disrupts the quality of the bus service nor becomes burdensome for the transit agencies. Such a phased implementation hinges on several technical and financial considerations which are often inter-linked and limited by some constraints. To address this complex problem, the Guidebook suggests a six-step approach and two decision trees for transit agencies’ reference for route prioritization and implementation planning

Regulatory environment in the EU already mandates public transport providers (PTP) to detail their cost accounting to the level of each line they operate. Models used, however, fail to utilise the level of precision state of the art technology would allow for; therefore, state-owned providers become uncompetitive. Implementing new technologies such as electric buses have high investment costs; thus, reconsidering the cost structure of an operator is essential. The aim of this paper is to introduce an innovative cost calculation method for battery electric bus operation. The novelty of the model is its foundation on telemetric data generated by sensors hosted in electric buses and the consequent use of marginal consumption costs instead of averages based on aggregations. The model introduced focuses on the cost of energy consumption, examines influencing factors, such as the effect of meteorological externalities on auxiliary systems, and considers driving dynamics. Nonetheless, fix costs such as amortisation and labour costs are also accounted for to give a complete picture of per passenger numbers. The model developed was applied as a case study to prove its applicability. We found that the climbed elevation positively correlates, while the number of stops served at a given distance negatively correlates with the increase in consumption. The model is better suited for improving the operative competitiveness of PTPs rather than as a tool for regulatory compliance.

This report is available at no cost from the National Renewable Energy Laboratory (NREL) at www.nrel.gov/publications. U.S. Department of Energy (DOE) reports produced after 1991 and a growing number of pre-1991 documents are available free via www.OSTI.gov.

Electrifying bus transit has been deemed as an effective way to reduce the emissions of transit vehicles. However, some concerns about on-board battery hinder its further development. Recently, dynamic wireless power transfer (DWPT) technologies have been developed, which enable buses to charge in-motion and overcome the drawback (short service range) with opportunity charging. This paper proposes a mathematic model which optimizes the locations for DWPT devices deployed at stops and size of battery capacity for battery electric buses (BEB) in a multi-route network, which considers the battery’s service life, depth of discharge and weight. A tangible solution algorithm based on a genetic algorithm (GA) is developed to find the optimal solution. A case study based on the bus network from Xi’an China is conducted to investigate the relationship among optimized costs, greenhouse gas (GHG) emissions, battery service life, size of the battery capacity and the number of DWPT devices. The ...

This study investigates the impacts of vehicular, operational, topological, and external parameters on the energy consumption (EC) of battery-electric buses (BEBs) in transit operation. Furthermore, the study develops a data-driven prediction model for BEB energy consumption in transit operation that considers these four parameters. A Simulink energy model is developed to estimate the EC rates and validated using the Altoona’s test real-world data. A full-factorial experiment is used to generate 907,199 scenarios for BEB operation informed by 120 real-world drive cycles. A multivariate multiple regression model was developed to predict BEB’s EC. The regression model explained more than 96% of the variation in the EC of the BEBs. The results show the significant impacts of road grade, the initial state of charge, road condition, passenger loading, driver aggressiveness, average speed, HVAC, and stop density on BEB’s energy consumption, each with a different magnitude. The study concl...

The goal of Sustainable Development Electrification of Transit is to contribute to Canada’s capacity for investment, implementation, and assessment of Zero Electric Buses (ZEB). A sustainable transportation system is one that is safe, affordable, accessible, efficient and resilient, and that contributes minimal emissions of carbon and other pollutants.  The adoption of Zero-Emissions Bus (ZEB) buses fits squarely within a sustainable transit electrification strategy (STES). ZEB transit is identified by all levels of government in Canada and transit authorities as a critical step in meeting clean growth goals and zero-emissions targets. ZEB includes transit infrastructure, battery (BEB) and hydrogen (FCEB) as well as hybrid diesel buses across Canada. The research team analyzed Canadian and international literature, governmental, academic and industry data sources, and sought and characterized analytics tools that could support analysis and implementation of ZEB. These sources were stored in searchable databases and analyzed according to sub-themes relevant to Transportation Systems, Environmental, Economic, Social (including Equity and Health), ZEB and Analytic Technology categories. Data collection methods and types as well as equity considerations (GBA+) were considered for all sources. Stakeholder interviews and a workshop supplemented secondary source analysis. Researchers deployed a thematic analytics tool to derive key themes in literature and interviews. If achieved, impacts are far-reaching: reduction of emissions and particulates, improved quality of urban life through less pollution and noise, improved health of residents, more equitable and affordable reach and choice of transit, industry growth, and green job creation. Secondary benefits include densification and cost reduction of pollution-induced disease for the healthcare system.

The electricity generation/supply and transportation sectors are the two largest contributors to greenhouse gas (GHG) emissions in the U.S., and vehicle-to-grid (V2G) technology is a rapidly emerging solution to reduce these emissions with the adoption of battery-electric (BE) vehicles. Deployments of BE transit and school buses are expected to have larger battery capacities than passenger vehicles, making them more feasible candidates for V2G service. Five electricity generation regions are considered for cash flow analysis of BE and diesel transit and school buses over their entire respective lifetimes with the allowance of V2G services' net revenue. Besides, the environmental benefits of using the V2G system are studied in place of combustion power generation plants for the regulation services of each study region. Air emission externalities are another crucial issue for bus operations because buses are operated near highly populated areas, so these externalities are also studied in this research with the benefits of a V2G emission reduction potential taken into account. The analysis concluded that BE transit and school buses with V2G application have potential to reduce electricity generation related greenhouse-gas emissions by 1067 and 1420 tons of CO 2 equivalence (average), and eliminate $13,000 and $18,300 air pollution externalities (average), respectively.

The science supporting the sport of motorcycle riding is best understood by looking at multiple moving parts of the motorcycle. The following research features the all-electric, 2020 Zero Motorcycle Sr/S. The physics underlying motorcycle motion is specifically understood by examining key components of the motorcycle including: the energy source (the battery), the forces acting on the motorcycle, and the technology accessible to the motorcycle rider. By examining the relation between the rider's position on the motorcycle, earth's gravitational pull & friction, torque, and rider awareness, the reader of this paper will therefore understand fundamental physics of safe motorcycle riding.

Keith D. Patch combines his more than 25 years of broad-ranging energy, water and food-based technical and business management experience to highlight the current state of green hydrogen production and utilization. This involves end uses of demanding metropolitan bus and train transit applications, long-distance trucking, ocean-faring maritime, air travel, and other mobility vectors. Chemical/petrochemical/industrial uses are also addressed.