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Alternative fuel vehicles can play an important role in addressing the challenges of climate change, energy security, urban air pollution and the continued growth in demand for transportation services. The successful commercialization of alternative fuels for vehicles is contingent upon a number of factors, including vehicle cost and performance. Among fuel infrastructure issues, adequate refueling availability is one of the most fundamental to successful commercialization. A commonly cited source reports 164,300 refueling stations in operation nationwide. However, from the perspective of refueling availability, this nationwide count tends to overstate the number of stations required to support the widespread deployment of alternative fuel vehicles. In terms of spatial distribution, the existing gasoline station networks in many urban areas are more than sufficient. We characterize a sufficient level of urban coverage based upon a subset of cities served by relatively low-density station networks, and estimate that some 51,000 urban stations would be required to provide this sufficient level of coverage to all major urban areas, 33 percent less than our estimate of total urban stations. This improved characterization will be useful for engineering, economic and policy analyses.

During the first decades of the 20th century, a variety of gasoline refueling methods supported early US gasoline vehicles and successfully alleviated consumer concerns over refueling availability. The refueling methods employed included cans, barrels, home refueling outfits, parking garage refueling facilities, mobile stations, hand carts and curb pumps. Only after robust markets for gasoline vehicles had been firmly established did the gasoline service station become the dominant refueling method. The present study reviews this history and draws analogies with current and future efforts to introduce hydrogen as a fuel for vehicles. These comparisons hold no predictive power; however, there is heuristic value in an historical review of the first successful and large-scale introduction of a vehicle fuel. From an energy policy perspective, these comparisons reinforce the importance of a long-term and portfolio approach to support for technology development and innovation.

Tire purchasing and disposal impose considerable cost and waste burdens on private vehicle owners and fleet managers. This research investigates tire maintenance management practices and tire-related vehicle technologies that have the potential to relieve some of these burdens. We investigate behavior, attitudes, and practices of fleet personnel and individual drivers as they relate to tire attributes and technologies. Based on this research, we analyze and recommend critical practices that could improve tire purchasing, tire management, average tire life within existing vehicles in vehicle fleets. We evaluate the tire wear and energy use of various tire technologies and improved fleet tire management and find several fleet practices that offer substantial potential improvements in tire-related energy and waste consequences. Advancements in three particular areas – tire pressure monitoring, nitrogen as a tire inflation medium, and the selection of tires with lower rolling resistance – are commercially available and promising in terms of their potential benefits. Additionally, to demonstrate and empirically test the potential impact of nitrogen as an inflation medium for tires, we deploy several technologies on fleet vehicles, including data acquisition systems for retrieval of information from fleet vehicles and nitrogen inflation equipment at the California Department of General Services vehicle fleet facility. We develop the accompanying experimental design for testing the impact of nitrogen inflation on these fleet vehicles. This experiment is created in such a way that the fleet personnel can undertake the experimental testing and statistically evaluate the impact of nitrogen inflation on their vehicle fleet. From our findings, we develop best practices recommendations, which are meant to serve as a guide for improving tire practices in vehicle fleets.

Among heavy industrial sectors worldwide, the steel industry ranks first in carbon dioxide (CO2) emissions. Technologies that produce direct reduced iron (DRI) enable the industry to reduce emissions or even approach net‐zero CO2 emissions for steel production. Herein, comprehensive cradle‐to‐gate (CTG) life cycle analysis (LCA) and techno‐economic analysis (TEA) are used to evaluate the CO2 emissions of three DRI technologies. Compared to the baseline of blast furnace and basic oxygen furnace (BF–BOF) technology for steel making, using natural gas (NG) to produce DRI has the potential to reduce CTG CO2 emissions by 33%. When 83% or 100% renewable H2 is used for DRI production, DRI technologies can potentially reduce CO2 emissions by 57% and 67%, respectively, compared to baseline BF–BOF technology. However, the renewable H2 application for DRI increases the levelized cost of steel (LCOS). When renewable natural gas (RNG) and clean electricity are used for steel production, the CTG CO2 emissions of all the DRI technologies can potentially be reduced by more than 90% compared to the baseline BF–BOF technology, although the LCOS depends largely on the cost of RNG and clean electricity. [ABSTRACT FROM AUTHOR]

The usage of hydrogen fuels as alternate fuels in China and United States transportation sector is discussed.

While fuel cell vehicles are being prepared for limited production by 2003 or 2005, it is unclear what type of fueling infrastructure will support these vehicles when true mass production begins. If a significant number of mass-produced fuel cell vehicles are to carry hydrogen onboard, an extensive hydrogen refueling system must be initiated before the general public will feel comfortable purchasing these vehicles. This paper explores three approaches to estimating how many hydrogen fueling stations might be required for a large portion of the US population, or a large region such as California, to have convenient access to hydrogen fueling. The approaches are based upon the number of existing gasoline stations, metropolitan land areas, and density of interstates and urban arterial roads. Preliminary results suggest that between 4500 and 17,700 hydrogen stations would be required to initiate a hydrogen infrastructure for fuel cell vehicles. Scenario analysis is used to explore the cost of hydrogen during and after the initiation process. [Copyright &y& Elsevier]