Refine Your Search

Search Results

Viewing 1 to 6 of 6
Technical Paper

Cost Effective Annual Use and Charging Frequency for Four Different Plug-in Powertrains

Vehicles with electrified powertrains, such as hybrid electric vehicles (HEVs), plug-in HEV (PHEVs), and AEVs (all-electric vehicles using grid-supplied battery energy exclusively), are potentially marketable because of low operating costs, but each comes with a significant initial cost penalty in comparison to a conventional vehicle (CV) powered by an internal combustion engine. Accordingly, a high rate of utilization is necessary for cost effectiveness. This paper examines the projected future (2020) cost effectiveness of several alternative powertrains within a standard compact sedan glider: an AEV and a set of selected input-split and output-split HEV and PHEV powertrains with various battery power and energy storage capabilities. Vehicle performance and consumption rates of fuel and electricity were estimated using vehicle simulations, and vehicle prices were estimated using cost models.
Technical Paper

Evaluating Commercial and Prototype HEVs

In recent years, vehicle manufacturers have made great progress in developing and demonstrating commercially available and prototyped hybrid electric vehicles (HEVs). These vehicles include commercially available gasoline hybrid cars (Toyota Prius and Honda Insight) and Partnership for the Next Generation Vehicle (PNGV) diesel hybrid prototypes (Ford Prodigy, GM Precept, and DaimlerChrysler ESX3). In this paper, we discuss tested and claimed fuel benefits and performance of these commercial and prototyped HEVs relative to conventional vehicles (CVs) that are otherwise similar to these HEVs, except for hybridization. We also describe a reverse-engineering approach to de-hybridize or “conventionalize” these five existing commercial and prototyped HEVs. Because these commercial and prototyped HEVs represent a variety of technological choices, configurations, and development stages, this analysis gives us in-depth knowledge about how each of these vehicles achieves high efficiency.
Technical Paper

Hybrid Options for Light-Duty Vehicles

Hybrid electric vehicles (HEVs) offer great promise in improving fuel economy. In this paper, we analyze why, how, and by how much vehicle hybridization can reduce energy consumption and improve fuel economy. Our analysis focuses on efficiency gains associated solely with vehicle hybridization. We do not consider such other measures as vehicle weight reduction or air- and tire-resistance reduction, because such measures would also benefit conventional technology vehicles. The analysis starts with understanding the energy inefficiencies of light-duty vehicles associated with different operation modes in U.S. and Japanese urban and highway driving cycles, with the corresponding energy-saving potentials.
Technical Paper

Lifecycle Analysis for Freight Transport

This paper evaluates the total lifecycle impacts for hauling freight long distances over land in the United States. The dominant modes of surface freight transport in the United States are large motor trucks (tractor-semitrailer combinations) and trains. These vehicles account for a significant portion of the transportation sector's petroleum usage and atmospheric emissions (among which nitrogen oxides and particulate matter are especially important). The objective of this paper is to evaluate the potential for reductions in energy use (in particular, petroleum use) and atmospheric emissions that result from freight transport, possibly as the result of research and development on improved technology or alternative fuels, such as Fischer-Tropsch diesel and natural gas, or from mode shifts in competitive markets. The impacts examined include energy use, both in toto and the petroleum fraction, and emissions of greenhouse gases and nitrogen oxides and particulate matter.
Technical Paper

Scenario Analysis of Hybrid Class 3-7 Heavy Vehicles

The effects of hybridization on heavy-duty vehicles are not well understood. Heavy vehicles represent a broader range of applications than light-duty vehicles, resulting in a wide variety of chassis and engine combinations, as well as diverse driving conditions. Thus, the strategies, incremental costs, and energy/emission benefits associated with hybridizing heavy vehicles could differ significantly from those for passenger cars. Using a modal energy and emissions model, we quantify the potential energy savings of hybridizing commercial Class 3-7 heavy vehicles, analyze hybrid configuration scenarios, and estimate the associated investment cost and payback time.
Technical Paper

Total Fuel Cycle Impacts of Advanced Vehicles

Recent advances in fuel-cell technology and low-emission, direct-injection spark-ignition and diesel engines for vehicles could significantly change the transportation vehicle power plant landscape in the next decade or so. This paper is a scoping study that compares total fuel cycle options for providing power to personal transport vehicles. The key question asked is, “How much of the energy from the fuel feedstock is available for motive power?” Emissions of selected criteria pollutants and greenhouse gases are qualitatively discussed. This analysis illustrates the differences among options; it is not intended to be exhaustive. Cases considered are hydrogen fuel from methane and from iso-octane in generic proton-exchange membrane (PEM) fuel-cell vehicles, methane and iso-octane in spark-ignition (SI) engine vehicles, and diesel fuel (from methane or petroleum) in direct-injection (DI) diesel engine vehicles.