10922 Pdf

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This reduction would be the result of the increased efficiency of hydrogen generation with the new technologies. Topics covered include the hydrogen end-use technologies, transportation, hydrogen production technologies, and transition issues for hydrogen in vehicles. To search the entire text of this book, type in your search term here and press Enter.

Looking for other ways to read this? New car sales have grown less rapidly. That impact can be seen as the difference in Figure between the gasoline consumption and the consumption with hydrogen and hybrid vehicles.

Although a transition to hydrogen could greatly transform the U. Figure shows the fuel economy assumed for the three classes of vehicles over time. This is only a small fraction of the million tons required for full replacement of gasoline for light-duty vehicles.

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Technologies that use biomass as a feedstock require substantial acreage in order to grow the biomass. Additional uses of natural gas would lead to additional imports. However, if gasoline use is reduced to a very small portion of refined products, new refining processes may be needed. Both the rate of sequestration and the cumulative amount of sequestration needed can be expected to pose very great challenges.

Note that this figure includes two scales, measuring gasoline use in millions of barrels per day right scale and in quadrillion British thermal units Btu per year left scale. Figure also displays two other trajectories of gasoline consumption.

It continues to maintain the discussion about pure options in which all of the hydrogen is produced from a given feedstock. Hydrogen based on distributed natural gas would be somewhat more costly. In order to examine this issue, estimates were developed of the amount of natural gas that would be used if all of the hydrogen were generated using one of the natural-gas-based technologies. In addition to impacts on natural gas, livro dieta do tipo sanguineo.pdf the committee has estimated impacts on several other domestic resources.

The additional use of natural gas can be compared with the reduced use of gasoline. Coal-based hydrogen generation would require increased U. In developing the analyses, the committee made quantitative estimates of some of the impacts believed to be most important, but it was not able to examine all of the possible impacts. Figures and provide similar data for future technologies for fossil fuels and nuclear thermal energy and for renewables and distributed electrolysis, respectively. Using current technologies, the land required for biomass to produce all of the hydrogen for fueling light-duty vehicles would be as large as the total amount of cropland in the United States.


NAVMC 10922 (REV. 4 01) PDF

Figure shows the consumption of hydrogen by light-duty vehicles estimated for this vision. And the committee does not examine any of the redistributional consequences of a shift to hydrogen. In this chapter, the committee examined its vision of how the energy system might operate if hydrogen-fueled vehicles were broadly adopted in place of gasoline-fueled vehicles. In this case, whether energy security is improved or harmed depends on whether the security benefits from reduced oil imports are greater than the security costs of increased natural gas imports.

Thus, the conventional vehicle cost is consistent with what Americans have been willing to pay for the fuel costs of driving itself only a fraction of the total costs of driving. For biomass production, it examined the amount of land that would be required to grow the crops used as feedstocks.

10922 pdf

Figures and provide these total annual costs for the current technologies, for fossil fuels, and for renewables and distributed electrolysis, respectively. Figure shows that a transition to hydrogen in light-duty vehicles could sharply reduce the use of gasoline and thus could reduce the importation of oil. Some of the technologies would use domestic resources without increasing the importation of other energy from potentially unstable parts of the world.

The committee summarizes here some of the most important of these impacts on such domestic resources. The committee considers this vision to repre-. Jump up to the previous page or down to the next one.

For every additional hydrogen vehicle in this analysis, there is one fewer hybrid electric vehicle. Do you enjoy reading reports from the Academies online for free? This cost is consistent with current cost per mile driven and growth in vehicle miles influenced by population and income growth.

The penetration of hybrids into the marketplace, even absent hydrogen-fueled vehicles, could reduce fuel costs by tens of billions of dollars per year in the United States. Likewise, the biomass technologies are substantially more costly.

10922 pdf

In making this assumption, however, the committee has not conducted its own analysis or projection of whether this goal will be achieved. Thus, it is not clear what fraction of this increase in natural gas use would translate into increases in natural gas imports. Figures and respectively provide annual and cumulative sequestration estimates for possible future technologies. The economic impacts examined are the costs to the United States as a whole from fueling the fleet of light-duty vehicles.

Impacts on the use of natural gas were examined. Existing refineries swing between summer and winter differences in demand for gasoline and distillate fuels. Costs of the infrastructure to fuel the vehicles are included in the supply costs for hydrogen. Starting with this optimistic vision, estimates are made of the consumption of gasoline and of hydrogen for the first half of this century. The committee does not examine these potentially important consequences.

An increase in demand would cause an increase in price, which in turn could increase domestic supply. For coal-based hydrogen production, it examined the amount of coal that would be used over time. Some technologies could lead to sharp reductions in the amount of energy imported from unstable parts of the world, but not all could lead to such energy security improvements.

10922 pdf

The implications of broad adoption of hydrogen for other purposes, such as electricity generation, are not examined in depth. This vision is not a prediction of the diffusion of hydrogen technologies into the fleet of vehicles, depending as it does on such a large number of factors that are inherently uncertain. The total vehicle miles traveled for each type of car is proportional to the number of each type on the road, adjusted so that new cars are assumed to be driven more than older cars are. But the technologies based on distributed electrolysis operating either entirely on grid-supplied electricity or partially on photovoltaic-supplied.