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Hybrid electric vehicles (HEVs) may have key fuel economy and emissions advantages over current conventional vehicles, but they have drawbacks such as frequent engine starts that can slow down market penetration of HEVs. First, the hydrocarbon emissions due to the numerous engine starts would make newly developed HEV powertrains even more demanding on the emission control system. Second, frequent starts may make the engine deteriorate quickly. This study is an attempt to gain a better understanding of the engine start characteristics of two limited-production HEVs (Toyota Prius and Honda Insight). Using fast-response (5 ms) hydrocarbon and NO (nitric oxide) analyzers, the transient emissions were measured in the engine exhaust ports during cold and hot engine starts. On the basis of the experimental findings, several recommendations were made to improve performance and emissions of future HEVs.

The Cooperative Automotive Research for Advanced Technology (CARAT) program is designed to accelerate the commercialization of innovative technologies that will overcome barriers to achieving the goals of the Partnership for a New Generation of Vehicles Program. Aimed at harnessing the creativity and capabilities of American small businesses and colleges and universities, this unique technology R&D program seeks to develop and bring advanced technologies into use in production vehicles at a faster rate. CARAT's focus is developing and commercializing technology that overcomes key technical barriers preventing the production of vehicles with ultra-high fuel efficiency. CARAT begins with technologies that already have a firm technical basis and, through a unique three-stage process, ends with fully validated technologies ready for mass production. The program is open to all U.S. entrepreneurs and small businesses, colleges, and universities.

The 1994 Hybrid Electric Vehicle Challenge provided the backdrop for collecting data and developing testing procedures for hybrid electric vehicle technology available at colleges and universities across North America. The data collected at the competition was analyzed using the HEV definitions from the draft SAE J1711 guidelines. The energy economy, percentage of electrical to total energy used, and acceleration performance was analyzed for any correlation between the over-the-road data and the commuter-sustaining, commuter-depleting, and reserve-sustaining hybrid vehicles. The analysis did not provide any direct correlation between over-the-road data and the three hybrid types. The analysis did show that the vehicle configurations provide the best information on vehicle performance. It was also clear that a comprehensive data analysis system along with a well-defined testing procedure would allow for a more complete analysis of the data.

The U.S. Department of Energy sponsored several student engineering competitions in 1993 that provided useful information on electric and hybrid electric vehicles. The electrical energy usage from these competitions has been recorded with a custom-built digital meter installed in every vehicle and used under controlled conditions. When combined with other factors, such as vehicle mass, speed, distance traveled, battery type, and type of components, this information provides useful insight into the performance characteristics of electrics and hybrids. All the vehicles tested were either electric vehicles or hybrid vehicles in electric-only mode, and had an average energy economy of 7.0 km/kWh. Based on the performance of the “ground-up” hybrid electric vehicles in the 1993 Hybrid Electric Vehicle Challenge, data revealed a 1 km/kWh energy economy benefit for every 133 kg decrease in vehicle mass.

The Natural Gas Vehicle (NGV) Challenge '92, was organized by Argonne National Laboratory. The main sponsors were the U.S. Department of Energy the Energy, Mines, and Resources - Canada, and the Society of Automotive Engineers. It resulted in 20 varied approaches to the conversion of a gasoline-fueled, spark ignited, internal combustion engine to dedicated natural gas use. Starting with a GMC Sierra 2500 pickup truck donated by General Motors, teams of college and university student engineers worked to optimize Chevrolet V-8 engines operating on natural gas for improved emissions, fuel economy, performance, and advanced design features. This paper focuses on the results of the emission event, and compares engine mechanical configurations, engine management systems, catalyst configurations and locations, and approaches to fuel control and the relationship of these parameters to engine out and tailpipe emissions of regulated exhaust constituents.

A follow-up to the 1989 Society of Automotive Engineers (SAE) Methanol Marathon called the Methanol Challenge was held in April 1990. One of a series of engineering student competitions using alternative fuels organized and conducted by the Center for Transportation Research at Argonne National Laboratory, the Methanol Challenge pushed the technology for dedicated M85 (85% methanol, 15% hydrocarbon fuel) methanol passenger cars to new levels. The event included complete federal exhaust emissions, cold-start and driveability, performance, and fuel economy testing. Twelve teams of student engineers from the United States and Canada competed in the Challenge using Chevrolet Corsicas donated by General Motors (GM) to the schools. The winning car, from the University of Tennessee, simultaneously demonstrated extremely low emissions, dramatically increased performance, and significantly improved fuel economy.

The introduction of ceramic engine components and ceramic-intensive engines for transportation applications will significantly affect the U.S. economy and the state of International competition in this advanced-technology field. A worldwide Delphi survey of more than 150 experts in this field provided data on the expected timing and rate of that led to market penetration projections. By the mid-1990s, according to the projections, a substantial number of ceramic engine components will be in production and ceramic-intensive engines will be introduced. Annual energy savings impacts are projected to be 380 trillion Btu, worth $5.5 billion, in 2010. The U.S. gross national product (GNP) could differ by $42 billion (in 1986 dollars) in 2001, depending on whether the U.S. or another nation leads in manufacturing engine ceramics.

A study is described that was conducted to provide a realistic technical and economic assessment of the use of advanced ceramic materials technology for heat engines in transportation applications. Key results from a worldwide Delphi survey are presented on the expected timing and rate of market development for ceramic engine components and engines. These results show that, by the mid 1990s, a substantial number of ceramic engine components will be in production and ceramic-intensive engines will be introduced. Also presented in the study are benefits and barriers to the use of ceramic technology in heat engines and other relevant factors influencing its rate of adoption. A modeling approach is presented that uses the survey data to produces a series of market penetration curves for individual ceramic engine components for light- and heavy-duty applications under different scenarios.

The development of high-strength structural ceramics has many implications for advanced engine technology. Turbocharger rotors are an ideal early application of structural ceramics and are already in production in small volumes. Aside from the technical achievement this represents, what are the measurable benefits to employing this new technology to production vehicles from the manufacturer's and drivers point of view? This paper examines the results of a number of back-to-back performance tests of production vehicles equipped with ceramic and conventional turbochargers. The purpose was to more clearly quantify the benefits of this advanced turbo-charger technology. A variety of acceleration tests were conducted by both independents and manufacturers. In addition, personal observations are included from more than 20,000 miles and a year of experience driving a production turbocharged car with a ceramic turbocharger.