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In recent years alternative automobile power technologies have received increased attention from OEM's, special interest groups, and the public. Plausible power technologies now include internal combustion engines, batteries, fuel cells, and a variety of hybrid technologies. The merits of each of these technologies as a means to move personal and fleet transportation into the next century have been highly debated. One technology that has emerged as a viable alternative to the internal combustion engine is the fuel cell. Considering arguments on all sides of the debate, the authors describe the results of a systematic, focused examination of the sustainability of fuel cells for transportation and discuss strategies for sustainable technology design. Sustainable technologies are those that contribute to preserving or improving societal quality, the environment, and the economy for future generations.

The use of a soy-based diesel fuel (biodiesel) has potential advantages over the use of a conventional petroleum diesel fuel including: Reduced dependence on foreign petroleum Lowering of greenhouse gas emissions Less air pollution and related public health risks in urban areas A life cycle study performed by the U.S. Department of Energy's National Renewable Energy Laboratory, the U.S. Department of Agriculture's Office of Energy and Ecobalance (completed in May 1998) helped to quantify the environmental benefits of the “cradle-to-grave” production and use of biodiesel. The study showed, for example, that substituting 100% biodiesel for petroleum diesel in urban buses reduced the life cycle emissions of carbon dioxide (CO2) by 78%. The study also pointed out some trade-offs of using biodiesel including increased life cycle hydrocarbon and NOx emissions.

An increase in engine and vehicle efficiency usually requires an increase in the severity of contact at the interfaces of many critical components. Examples of such components include piston rings and cylinder liners in the engine, gears in the transmission and axle, bearings, etc. These components are oil-lubricated and require enhancement of their tribological performance. Argonne National Laboratory (ANL) recently developed a carbon-based coating with very low friction and wear properties. These near-frictionless-carbon (NFC) coatings have potential for application in various engine components for performance enhancement. This paper presents our study of the tribological performance of NFC-coated steel surfaces when lubricated with fully formulated and basestock synthetic oils. The NFC coatings reduced both the friction and wear of lubricated steel surfaces. The effect of the coating was much more pronounced in tests with basestock oil.

The sulfur content in diesel fuel has a significant effect on diesel engine emissions, which are currently subject to environmental regulations. It has been observed that engine particulate and gaseous emissions are directly proportional to fuel sulfur content. With the introduction of low- sulfur fuels, significant reductions in emissions are expected. The process of sulfur reduction in petroleum-based diesel fuels also reduces the lubricity of the fuel, resulting in premature failure of fuel injectors. Thus, another means of preventing injector failures is needed for engines operating with low- sulfur diesel fuels. In this study, we evaluated a near-frictionless carbon (NFC) coating (developed at Argonne National Laboratory) as a possible solution to the problems associated with fuel injector failures in low-lubricity fuels.

During the past years advances in fuel efficiency of car engines did not result in the expected reduction in overall fuel consumption of new car generations. One reason is the increasing vehicle weight. In an overall–weight analysis of an automobile the engine and as part of it, the crankcase represents a single component with a high weight reduction potential. This paper discusses weight reduction strategies using lightweight materials and modern design approaches. The application of lightweight materials for new crankcase concepts implies comprehensive design considerations to achieve weight reductions as close as possible to the potential of the selected material. A specific approach for inline and V–engine crankcase concepts is discussed in detail. Engine weight reduction can also be achieved through substituting large and therefore heavy engines with small high performance engines.

The ULSAB-Advanced Vehicle Concepts Program is focused on the development of steel applications for vehicles to be produced beginning in the year 2004. A “holistic” total vehicle development approach will be applied, including styling, package, closures, suspension, etc. The understanding of the interactions of all vehicle subsystems, their optimization in respect to size, mass, and performance, will lead the program to an optimized steel intensive vehicle concept. Benchmarking will provide the data for building the basis of the target setting, after which the program target will be established and guidelines for the design will be created. The ULSAB-AVC Program concentrates on the design of two size lightweight vehicles: One size fitting in the most popular European C-class (so-called Golf class); and the second size similar to the North American PNGV class (Partnership for a New Generation of Vehicles*).

Hybrid electric vehicles (HEV's) offer additional flexibility to enhance the fuel economy and emissions of vehicles. The Real-Time Control Strategy (RTCS) presented here optimizes efficiency and emissions of a parallel configuration HEV. In order to determine the ideal operating point of the vehicle's engine and motor, the control strategy considers all possible engine-motor torque pairs. For a given operating point, the strategy predicts the possible energy consumption and the emissions emitted by the vehicle. The strategy calculates the “replacement energy” that would restore the battery's state of charge (SOC) to its initial level. This replacement energy accounts for inefficiencies in the energy storage system conversion process. User- and standards-based weightings of time-averaged fuel economy and emissions performance determine an overall impact function. The strategy continuously selects the operating point that is the minimum of this cost function.

There is a growing awareness of the business value of sustainable practices. Life cycle tools can be used to design and continually improve future vehicles as well as provide bottom line cost savings, increase the recycled content and recyclability of products, and reduce the hazardous substance content in products. Data collection and management procedures as well as advanced life cycle technologies and tools have been developed and implemented at some corporations to meet the global market demands to increase the recycled content and recyclability of automobiles and to reduce the hazardous substance content in automobiles. Voluntary take-back legislation in Europe, as well as strict domestic and international labeling and reporting requirements for plastics and hazardous substances have prompted automotive manufacturers to aggressively evaluate (1) the regulated substances contained in their automobiles and (2) the recyclability of their automobiles.

A Ford Explorer has been totally powered by internal combustion engine (ICE).fueled by hydrogen (H2) gas. H2 gas was generated on-board by a patented H2 generation technology - a safe, ambient temperature chemical reaction with a water based solution. The novel feature of this system is that H2 gas is safely generated on-board the vehicle as needed without resorting to bulky, pressurized cylinders. The entire H2 generation system easily fits within the engine compartment and beneath the floor of the vehicle making this one of the few practical zero emission vehicles that has room for 5 passengers and cargo while offering competitive performance and driving range to current SUVs.

A simulation has been developed at the Japan Automobile Research Institute to predict the fuel economy of HEVs, which are currently being developed in the advanced clean energy vehicle research and development project of MITI/NEDO (ACE Project). The ACE Project includes six types of HEV. The effect of hybrid components efficiency on fuel economy was evaluated by sensitivity coefficient. The results show that the fuel economy of HEVs can improve that of the base vehicle by two times. The sensitivity coefficient of the battery is largest in the FCEV, while that of the motor is largest in the series or series/parallel HEVs.

A discussion of the need for and the advantages of fuel cell systems and technologies is presented as is a description of the multi– / inter–disciplinary efforts currently underway at Virginia Polytechnic Institute and State University (Virginia Tech) for fuel cell system development. As part of these efforts, the Virginia Tech GATE (Graduate Automotive Technology Education) Center for Automotive Fuel Cell Systems is collaborating in research and education with both government and industry. The current focus of the center is the development of research, laboratory and educational programs in support of the design and implementation of fuel cell systems technology in advanced vehicles. Five GATE Fellowships are being funded by the DoE at the center starting Fall of 1999.

A detailed component performance, ratings, and cost study was conducted on series and parallel hybrid electric vehicle (HEV) configurations for several battery pack and main electric traction motor voltages while meeting stringent Partnership for a New Generation of Vehicles (PNGV) power delivery requirements. A computer simulation calculated maximum current and voltage for each component as well as power and fuel consumption. These values defined the peak power ratings for each HEV drive system's electric components: batteries, battery cables, boost converter, generator, rectifier, motor, and inverter. To identify a superior configuration or voltage level, life cycle costs were calculated based on the components required to execute simulated drive schedules. These life cycle costs include the initial manufacturing cost of components, fuel cost, and battery replacement cost over the vehicle life.

Honeywell is developing a 50-kW, high efficiency PEM fuel cell stack system (FCSS) for use in light-duty vehicle transportation under sponsorship from the Department of Energy (DOE) and the South Coast Air Quality Management District. The performance goals of the FCSS include weight, volume, cost, efficiency, and transient performance. The project includes design, testing, and delivery of the FCSS to DOE. A conceptual system design is presented including trade study results and the technology gaps that must be bridged to meet the DOE goals.

IGT and its subcontractors, Superior Graphite Corporation and Stimsonite Corporation identified moldable blends of graphites, resins, and additives and produced a molded composite graphite bipolar separator plate that is equivalent in function and performance to state-of-the-art machined graphite plates. Complicated flow field designs can be formed by molding. Applications for patents for the blended components have been submitted and PEM Plates, LLC was formed to commercialize the production of the molded graphite bipolar separator plates. Material and production costs for commercial quantities of the plates are estimated to be within $10 / kW, depending on the complexity of the design of the bipolar plate and fuel cell stack.

Advanced battery safety is of concern for the successful commercialization of these technologies. The USABC (United States Advanced Battery Consortium) and PNGV (Partnership for a New Generation of Vehicles) are developing high power battery systems for use in electric and hybrid/electric vehicle applications. Part of the objectives of these programs is to establish and verify testing procedures regarding the safety and abuse resistance of particular batteries or battery technologies. This paper will discuss the status of abuse testing procedures that have been developed for battery systems. The goal of these tests is to determine the extent to which defined abuse conditions contribute to venting, rupture, release of hazardous substances, fire, smoke or uncontrolled energy releases. Areas of abuse testing that have been identified are (1) mechanical, (2) electrical, and (3) thermal.

The commonly known technology of field weakening for permanent-magnet (PM) motors is achieved by controlling the direct-axis current component through an inverter. Without using mechanical variation of the air gap, a new machine approach for field weakening of PM machines by direct control of air-gap fluxes is introduced. The demagnetization situation due to field weakening is not an issue with this new method. In fact, the PMs are strengthened at field weakening. The field-weakening ratio can reach 10:1 or higher. This technology is particularly useful for the PM generators and electric vehicle drives.

Hydrogen fuel cell powered systems might soon replace the conventional combustion engines used in today's vehicles. Fuel cells hold a great deal of promise for mobile applications including vehicles because they are environmentally friendly and can provide an alternative power supply. They may prove to be the keystone in making traditional electric vehicles a feasible everyday and long-range alternative to conventional combustion driven vehicles. One example of this type of electric vehicle is the New Jersey Venturer, which was equipped with a PEM fuel cell system to demonstrate the use of this new technology.

The objective of this paper is to discuss the challenge of increasing complexity in automotive electronics and the advanced semiconductor solutions which are being developed to simplify these systems. The main areas which are discussed are the increase in throughput / performance requirements, future implementations of multiplexed communications systems which provide high dependability, increasing memory requirements and the challenge of increased sensor implementation.

Because of the inherent advantageous energy conversion features of a fuel cell power system, it is a prime candidate technology to meet the national needs for a high mileage, low emission automotive engine replacement that can be realized with both near term and future fuels. This paper provides an overview of efforts to develop such an automotive power system and summarizes early data related to system integration efforts to attain U.S. Department of Energy (DOE) program goals for performance, emissions and multi-fuel operation. Efforts to date have led to the first testing of an integrated fuel cell power system utilizing gasoline.

The U.S. Department of Energy (DOE) and the U.S. automotive industry are collaborating on research and development of advanced compression ignition direct injection (CIDI) engine technology and polymer electrolyte membrane (PEM) fuel cells for automotive applications. Under the auspices of the Partnership for a New Generation of Vehicles (PNGV), the partners are developing technologies to power an automobile that can achieve up to 80 miles per gallon (mpg), while meeting customer needs and all safety and emissions requirements. Research on enabling technologies for CIDI engines is focusing on advanced emissions control to meet the proposed stringent Environmental Protection Agency emissions standards for oxides of nitrogen (NOx) and particulate matter (PM) in 2004, while retaining the high efficiency and other traditional advantages of CIDI engines.