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The Intergovernmental Panel on Climate Change (IPCC) has concluded that climate change is caused by human activities. This case study presents findings on the vehicle use by the Department of Health in Ekurhuleni, Gauteng province, South Africa. The objectives of this study are to estimate the carbon dioxide equivalent emissions of government fleet vehicles and to identify mitigation measures to reduce the vehicle carbon emissions. Both the World Resource Institute Greenhouse Gas Protocol (GHGP) and the United Kingdom Department of Environmental Forestry and Rural Affairs (DEFRA) methodologies were used. The study revealed that the government fleet vehicles emitted 1362 t CO2e for a five year period (2010 − 2014), which is equivalent to $ 9 071 of the South African carbon tax. Various measures to reduce CO2e emissions were recommended, money saving from fuel and potential revenue generating opportunities were identified, including the use of hybrid vehicles. [ABSTRACT FROM AUTHOR]

A revolution is underway in transportation, with a variety of electric vehicles rapidly coming to the fore. The switch from internal combustion engines to electric motors will change the world in many ways and is expected to help reduce the world’s carbon dioxide emissions. Inspired by this vision, leaders in China, France, and Britain have all proclaimed that they will effectively ban cars that aren’t electric by about 2040, while Volvo says all of its vehicles will be powered by electric motors in a few years. Other automakers have also announced that they are headed that way. But how far along is this revolution really? What challenges still need to be overcome to gain truly widespread acceptance on a scale that can combat climate change? Will the costs and the benefits of these new vehicles be equally spread among countries and companies? And while we all benefit in the long term, who will be the winners and the losers in our short-term world where Wall Street thinking predominates? [ABSTRACT FROM PUBLISHER]

Fuel-speed curves (FSC) are used to account for the aggregate effects of congestion on fuel consumption in transportation scenario analysis. This paper presents plausible FSC for conventional internal combustion engine (ICE) vehicles and for advanced vehicles such as hybrid electric vehicles, fully electric vehicles (EVs), and fuel cell vehicles (FCVs) using a fuel consumption model with transient driving schedules and a set of 145 hypothetical vehicles. The FSC shapes show that advanced power train vehicles are expected to maintain fuel economy (FE) in congestion better than ICE vehicles, and FE can even improve for EV and FCV in freeway congestion. In order to implement these FSC for long-range scenario modeling, a bounded approach is presented which uses a single congestion sensitivity parameter. The results in this paper will assist analysis of the roles that vehicle technology and congestion mitigation can play in reducing fuel consumption and greenhouse gas emissions from motor vehicles. [ABSTRACT FROM AUTHOR]

Assessment has become a central aspect of engineering education for evaluating student learning, attaining accreditation, and ensuring accountability. However, the final step of the assessment process, which requires assessment results be used to redesign courses and programmes, is appreciably underdeveloped in the literature. As such, this work suggests a process, based on the engineering problem-solving method, to analyse and act on problems and successes identified in the assessment results. The process is illustrated through an application to Colorado State University's new programme for Hybrid-Electric Vehicle Engineering, for which the redesign process was originally created. Readers will benefit by simplifying and systematising the essential aspect of the assessment process – application to course redesign – for use in both research and practice applications. [ABSTRACT FROM AUTHOR]

The sustainable development of vehicle propulsion systems that have mainly focused on reduction of fuel consumption (i.e. CO2emission) has led, not only to the development of systems connected with combustion processes but also to legislation and testing procedures. In recent years, the low carbon policy has made hybrid vehicles and fully electric vehicles (H/EVs) popular. The main virtue of these propulsion systems is their ability to restore some of the expended energy from kinetic movement, e.g. the braking process. Consequently new research and testing methods for H/EVs are currently being developed. This especially concerns the critical ‘use-cases’ for functionality tests within dynamic events for both virtual simulations, as well as real-time road tests. The use-case for conventional vehicles for numerical simulations and road tests are well established. However, the wide variety of tests and their great number (close to a thousand) creates a need for selection, in the first place, and the creation of critical use-cases suitable for testing H/EVs in both virtual and real-world environments. It is known that a marginal improvement in the regenerative braking ratio can significantly improve the vehicle range and, therefore, the economic cost of its operation. In modern vehicles, vehicle dynamics control systems play the principal role in safety, comfort and economic operation. Unfortunately, however, the existing standard road test scenarios are insufficient for H/EVs. Sector knowledge suggests that there are currently no agreed tests scenarios to fully investigate the effects of brake blending between conventional and regenerative braking as well as the regenerative braking interaction with active driving safety systems (ADSS). The paper presents seven manoeuvres, which are considered to be suitable and highly informative for the development and examination of H/EVs with regenerative braking capability. The critical manoeuvres presented are considered to be appropriate for examination of the regenerative braking mode according to ADSS. The manoeuvres are also important for investigation of regenerative braking system properties/functionalities that are specified by the legal requirements concerning H/EVs braking systems. The last part of this paper shows simulation results for one of the proposed manoeuvres that explicitly shows the usefulness of the manoeuvre. [ABSTRACT FROM AUTHOR]

In this article, the regenerative braking control of a permanent magnet motor/generator in a light fuel cell hybrid electric vehicle is presented. The control strategies for motoring and regenerative braking operations of a permanent magnet motor are explained in detail based on a hybrid power system control. Based on the proposed method, a simulation is performed to verify the approach. In addition, a prototype experimental test-bed is built for experimental verification, and the results are discussed. [ABSTRACT FROM AUTHOR]

This article addresses the problem of maintaining a stable rectified DC output from the three-phase AC generator in a series-hybrid vehicle powertrain. The series-hybrid prime power source generally comprises an internal combustion (IC) engine driving a three-phase permanent magnet generator whose output is rectified to DC. A recent development has been to control the engine/generator combination by an electronically actuated throttle. This system can be represented as a nonlinear system with significant time delay. Previously, voltage control of the generator output has been achieved by model predictive methods such as the Smith Predictor. These methods rely on the incorporation of an accurate system model and time delay into the control algorithm, with a consequent increase in computational complexity in the real-time controller, and as a necessity relies to some extent on the accuracy of the models. Two complementary performance objectives exist for the control system. Firstly, to maintain the IC engine at its optimal operating point, and secondly, to supply a stable DC supply to the traction drive inverters. Achievement of these goals minimises the transient energy storage requirements at the DC link, with a consequent reduction in both weight and cost. These objectives imply constant velocity operation of the IC engine under external load disturbances and changes in both operating conditions and vehicle speed set-points. In order to achieve these objectives, and reduce the complexity of implementation, in this article a controller is designed by the use of Genetic Programming methods in the Simulink modelling environment, with the aim of obtaining a relatively simple controller for the time-delay system which does not rely on the implementation of real time system models or time delay approximations in the controller. A methodology is presented to utilise the miriad of existing control blocks in the Simulink libraries to automatically evolve optimal control structures. [ABSTRACT FROM AUTHOR]

This paper analyses the feasibility of incorporating electric or hybrid vehicles in intermodal transport for the transportation of containers in the pre- and post haulage (PPH) operation. In Europe, the intermodal transport market is being strongly supported, as it is seen as one of the keystones of a sustainable mobility system policy. The introduction of environmentally friendly electric/hybrid vehicles for the pre- and post haulage operation would mean a further enhancement leading to a more complete ecological intermodal transport chain. PPH operations are usually no longer than 30 km, and, hence, could possibly be handled by electric or hybrid vehicles. Hybrid electric vehicles (HEV) combine electric and other drive systems, such as internal combustion engines, gas turbines and fuel cells. Hybrid electric vehicles merge the zero pollution and high efficiency benefits of electric traction with the high fuel energy density benefits of an energy source or thermal engine. The use of electrically driven vehicles for goods distribution has already been successfully proven in international demonstration projects, such as ELCIDIS. Transport of intermodal units (such as ISO containers), however, requires electric/hybrid heavy-duty goods vehicles, which are not readily available on the market, but for which the technology exists. Different possibilities are assessed as to their technical, financial, organizational and environmental feasibility and suitability. This analysis is based on a typical mission for pre-and post haulage operations, such as type of trips, distance, frequency, urban/suburban, etc. [ABSTRACT FROM AUTHOR]

Models of integrated vehicle systems are essential for designing hybrid vehicles by means of simulation-based optimization. Given the complexity of hybrid vehicle systems, designing is a time consuming process that requires the evaluation of a large number of different design configurations. Modelling and simulation can significantly reduce the design time through efficient design evaluations and reduced number of prototypes built. This work presents the development and reduction of an integrated hybrid vehicle model composed of an engine, drivetrain, hydraulics and vehicle dynamics subsystems. For model development the bond graph formulation is used because it facilitates the integration of component/subsystem models in different energy domains, supports hierarchical modelling and allows straightforward manipulation of the model. The model is configured for a medium size military truck, and implemented in the 20SIM modelling and simulation environment. After developing the model, an energy-based model reduction methodology is applied in order to generate a reduced vehicle model that provides more design insight. The generated reduced system model for the hybrid truck (compared to the full model) produces almost identical predictions, has almost half the size and calculates the system response 2.5 times faster. This computationally efficient reduced model can be used for vehicle design studies to further reduce the development time. [ABSTRACT FROM AUTHOR]

The internal combustion engine is one of the most persistent established technologies in today's world. However, its dominance may be eroding due to stringent air pollution standards set since the early 1990s, particularly in California. Several technologies have been proposed to replace the conventional engine, most notably the fuel-cell vehicle (FCV). Despite vast support from the automotive industry for this long-term technology, another technology is opening the market as we speak: the hybrid electric vehicle (HEV). Based on a sociotechnical analysis of these technologies, we show that the HEV should not be overlooked as a candidate for the dominant design in the automotive industry in favour of the FCV. Based on this analysis, we conclude with an outlook on the possibilities of the FCV and implications for policy-makers in encouraging sustainable mobility. [ABSTRACT FROM AUTHOR]