Carbon Management Implications for R&D in the Chemical Sciences and Technology (2001) / Chapter Skim
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6. Advanced Engine and Fuel Systems Development for Minimizing Carbon Dioxide Generation
6. Advanced Engine and Fuel Systems Development for Minimizing Carbon Dioxide Generation
Pages 93-110
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From page 93... ...
position on these subjects has been presented before. Specifically, "We believe there is enough cause for concern to warrant responsible actions to reduce global greenhouse gas emissions." Since reductions in carbon dioxide emissions are an essential part of this objective, I would like to discuss some of the options available to us in developing advanced engine and fuel systems for minimizing CO2 generation.
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From page 94... ...
With the world's population predicted to reach 7 billion by 2015, the global car park will grow to nearly 850 million vehicles over the next 15 years if the ownership rate remains at 12%. While this represents significant growth in the demand for our products, as an industry we need to be thinking bigger than this.
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From page 95... ...
The term "comparable vehicle" means that in addition to providing three times the fuel efficiency of today's cars, this new class of vehicle must also provide the same performance, load-carrying capacity, and range. These conditions must be in place while meeting applicable safety and emissions standards at the adjusted cost of a 1994 midsize sedan.
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From page 96... ...
96 100 Hydrogen Hydrogen Economy Economy 10 Nonfossil Hydrogen Methane H/C = 4.0 Methane Economy Oil H/C = 2.0 Coal H/C = 1.0 1 Wood H/C = 0.1 0.1 Hydrogen / Carbon Ratio 0.01 1800 1850 1900 1950 2000 2050 2100 2150 2200 Year FIGURE 6.3 The trend in hydrogen-to-carbon ratio in global energy consumption. NOTE: y-axis is logarithmic.
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From page 97... ...
Various improvements in fuel economy can be obtained through use of lightweight bodies, advanced spark ignition engine technologies such as direct injection, and advanced transmissions. The upper and lower ranges for each Technology Areas: 1997: Technology Selection • Advanced design simulations • Advanced high power batteries and high energy batteries • Alternate fuels, fuel storage • Auxiliary power units, including DI and turbine Narrow • Efficient air conditioning systems the Concept Production • Electric porpulsion componants Technology Vehicles Prototypes • Engine efficiency technologies Focus • Flywheels • Fuel cells • Fuel reformers • Low emissions technologies • New materials and structures for mass reduction • Ultrareceptors FIGURE 6.5 The "invent on schedule" plan for the PNGV program.
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From page 98... ...
Compression ignition engines provide a substantial increase in fuel efficiency, particularly when installed in hybrid powertrain configurations. In a separate category from internal combustion engines are fuel cell-powered vehicles operating on either gasoline or hydrogen.
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From page 99... ...
For example, in the case of compression ignition engines (Figure 6.10) , mechanical and electrical control technologies such as common rail fuel injection systems, direct electronic fuel injection with rate shaping, electronically controlled turbocharging and exhaust gas recirculation, and lean NOx catalysts and particulate traps will be required to meet emissions goals.
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From page 100... ...
In the case of spark ignition engines, the best options for fuels include highly reformulated gasoline with virtually no sulfur; alcohols derived from biomass; natural gas; or as the infrastructure develops, hydrogen. Engine modifications required High pressure, common rail fuel injection systems Direct electronic fuel injection with rate shaping Electrically controlled EGR and turbocharging Particulate traps and lean NOx catalysts Fuel modifications required No sulfur Reduced density Lower aromatics Potential use of oxygenates Lubricity additives FIGURE 6.10 Advanced engine and fuel requirements for reduced emissions from compression ignition engines.
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From page 101... ...
For compression ignition engines the most promising fuels include highly reformulated diesel fuel with virtually no sulfur; liquid hydrocarbons derived from natural gas; diesel fuels blended with specific oxygenate components; alcohols derived from biomass; or natural gas possibly blended with some percentage of hydrogen. Spark Ignition, Lean Burn Engines Highly reformulated gasoline Alcohols from biomass Natural gas Hydrogen Compression Ignition Engines Highly hydrocracked distillates (reformulated diesel)
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From page 102... ...
In addition, hydrogen enables a variety of advanced engine or propulsion technologies including "zero-emission" fuel cell vehicles, simplified fuel cell vehicle designs without the need for a fuel reformer, and internal combustion engines that have both improved efficiency and very low emissions (Figure 6.13)
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From page 103... ...
We are also comparing the efficiencies and utility of such storage methods with gasoline reformer-equipped vehicle designs. It's claimed that advanced tank designs for both gaseous and liquid storage, as well as advanced solid adsorption materials, can store between 5 and 10% hydrogen calculated as a fraction of the overall weight of the total fuel storage system.
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From page 104... ...
Both of these technologies require significant development to further improve generating efficiencies and reduce production costs. The other critical component of a hydrogen fuel transportation system is an infrastructure designed to compete with other forms of energy (Figure 6.18)
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From page 105... ...
transportation fuel needs could be produced from this source of biomass. Furthermore on a societal basis, we do not believe that transportation energy needs should compete with human food production.
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From page 106... ...
E-85 versions of the Chevrolet Suburban and Tahoe and GMC Yukon and Yukon XL sport utility vehicles equipped with the 5.3 liter V-8 have been added in model year 2001. Finally, it is worth noting that calculations conducted at Argonne National Laboratories have demonstrated that it is possible to reduce petroleum consumption by approximately 90% and essentially eliminate all of the CO2 generated by mobile sources through use of ethanol generated from cellulose (Figure 6.20)
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From page 107... ...
It is expected that future transportation fuels will continue the trend toward lower density and higher H/C ratios. Reformulated gasoline and diesel fuels will provide the opportunity to reduce CO2 generation through improved internal combustion engine efficiency meeting applicable emissions standards.
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From page 108... ...
I think we will get to the point where we can have a manageable amount of noble metal in the fuel cell. It may be that the first few fuel cell vehicles sold are over-designed in terms of noble metal usage, but we believe that fuel cells are a viable option.
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From page 109... ...
Alan Wolsky, Argonne National Laboratory: I recollect estimating that using today's technology and today's electricity prices, hydrogen from electrolysis of water was $11 per million British thermal units. That is expensive.
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From page 110... ...
All I can tell you right now is that our analyses have been based on total life-cycle energy and materials costs, and based on these total life-cycle analyses, we believe that ethanol from biomass is competitive. Ethanol from cellulose is more expensive than petroleum-based energy forms today, but there is a very real reason to think that improvements can be made in cellulose processing techniques that would allow us to bring the cost of the ethanol derived from cellulose down to a competitive level.
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