This paper evaluates how gasoline prices influences the average fuel economy of the existing automobile fleet. Higher fuel price affects fleet composition in two ways: immediate purchase decisions of new, more fuel efficient, vehicles and scrappage of old fuel inefficient gas-guzzlers. Gasoline costs account for 65% of the total operating costs of driving an automobile. Rational forward-looking...

(Received: January 8, 2012; Accepted: Februray 8, 2012) Abstract: The power industry is confronting challenges with seemingly conflicting goals. They provide the economy of scale needed to minimize the cost of production. Consumers, including industry, rely on affordable, dependable electrical energy. It’s an important part of our economy and our daily lifestyle. However, reducing emission leve...

To meet increasingly stringent emission regulations modern internal combustion engines require highly accurate control of the air-to-fuel ratio. The performance of the conventional air-to-fuel ratio feedback loop is limited by the combustion delay between fuel injection and engine exhaust, and by the transport delay for the exhaust gas to propagate to the air-to-fuel ratio sensor location. The ...

A series hydraulic hybrid concept (SHHV) has been explored as a potential pathway to an ultra-efficient city vehicle. Intended markets would be congested metropolitan areas, particularly in developing countries. The target fuel economy was ~100 mpg or 2.4 l/100km in city driving. Such an ambitious target requires multiple measures, i.e. low mass, favorable aerodynamics and ultra-efficient power...

INTRODUCTION The fuel tax system used for financing the U.S. highway transportation infrastructure is becoming less effective and less equitable over time. While many people prefer the relatively less fuel-efficient sport utility vehicles, the general trend over time is toward more fuel efficiency. While the popularity of light trucks and SUVs has slowed the increase in average fuel economy for...

This paper compares four transportation energy conservation strategies using a comprehensive evaluation framework that takes into account how each strategy affects annual vehicle travel, and therefore mileage-related impacts such as traffic congestion, road and parking facility costs, and crashes. These mileage-related impacts tend to be large in magnitude compared with energy conservation bene...

Hybrid electric fuel cell vehicles are studied using a system perspective that explores the tradeoffs among fuel economy, acceleration, and other vehicle attributes. Design decisions are derived from an enterprise decision-making model that seeks to maximize profit. Uncertainties stemming from manufacturing variability, customer preferences, and market response to fuel price fluctuations are al...

This paper introduces an online and intelligent energy management controller to improve the fuel economy of a power-split plug-in hybrid electric vehicle (PHEV). Based on analytic analysis between fuelrate and battery current at different driveline power and vehicle speed, quadratic equations are applied to simulate the relationship between battery current and vehicle fuel-rate. The power thres...