In the past, the committee has been critical of the PNGV systems analysis team for not providing systematic evaluations of candidate technologies in terms of their potential initial costs, the total cost of vehicle ownership, weight impacts, and effects on the infrastructure. The lack of analyses seems to have had a minimal impact, however, on the selection of a configuration for the concept demonstration vehicles because only a limited number of technologies had reached a level of maturity that would justify their selection. It is not surprising, therefore, that all three USCAR partners chose configurations with major weight reductions, reduced aerodynamic drag, reduced accessory loads, low rolling resistance tires, low-loss transmissions, CIDI engines, and parallel hybrid configurations that allow some regeneration of braking energy (see Appendix F). But studies evaluating economic viability for the consumer market have not yet been done.

Vehicles that meet all PNGV targets for aerodynamics, weight reduction, and low rolling resistance are currently projected to achieve less than 65 mpg with any of the nonhybrid combustion engine power trains being considered. Therefore, they would save, at most, about 3,300 gallons of fuel over the lifetime of the vehicle (see Table 6-1). Although 65 mpg falls short of the 80 mpg target, which would nominally save about 3,725 gallons of fuel, the nonhybrid vehicle has the potential to provide 85 percent of the target fuel savings. Assuming that the vehicle meets the PNGV requirements for emissions, safety, size, comfort, range, and driveability, it is appropriate to consider whether it meets the requirement for "equivalent cost of ownership." The principal elements of the cost of ownership are initial cost and lifetime fuel and maintenance costs. This nonhybrid vehicle would have similar complexity to existing diesel power train vehicles, suggesting that they would require no substantial change in maintenance costs and that the initial cost, assuming PNGV component cost targets were met, would increase by less than the value of lifetime fuel savings. Consequently, the total cost of ownership for the nonhybrid vehicle could be lower than the cost for today's baseline conventional vehicle.

Even in the most optimistic projection, a hybrid vehicle is estimated to offer about a 20 percent improvement in fuel economy. For an HEV, the 80 mpg target, therefore, would save less than 425 gallons of fuel over the lifetime of the vehicle over a nonhybrid vehicle with a fuel economy of 65 mpg. But the HEV would be more complex because of its motor/generator, battery, power conversion electronics, and switch gear and electronic controls, and even the most optimistic cost targets for HEVs are still in excess of the fuel savings by approximately an order of magnitude, not including the anticipated additional maintenance costs for the additional components. The cost of ownership would appear to increase markedly for the hybrid vehicle unless these are offset by

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