Review of the Research Program of the Partnership for a New Generation of Vehicles Seventh Report (2001) / Chapter Skim
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2. Development of Vehicle Subsystems
2. Development of Vehicle Subsystems
Pages 20-70
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From page 20... ...
To achieve the Goal 3 fuel economy target of 80 mpg (1.25 gallons per 100 miles) , the energy conversion efficiency of the chemical conversion system (e.g., a power plant, such as a compression-ignition direct-injection [CIDI]
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From page 21... ...
It is apparent that the fuel cell will not be feasible in a production-prototype vehicle by 2004. This leaves the internal combustion engine as the primary energy converter, and even using the most efficient one, the CIDI diesel engine, the three-times fuel economy target remains a stretch goal.
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From page 22... ...
There is a general sentiment that emission standards can be met with incremental development of known technology applied to homogeneous-charge sparkignition engines and probably with direct-injection spark-ignited gasoline engines. Using the spark-ignited engine, however, would result in a reduction in the vehicle's fuel economy compared with that of a diesel engine.
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From page 23... ...
Engine-Combustion System Developments The challenge of meeting the CARB LEV 2 and Tier 2 emission standards with a diesel engine was highlighted in the 2000 committee report (NRC, 2000~. A critical requirement is that tailpipe NOX and particulate matter (PM)
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From page 24... ...
The emission targets in the table are for the tailpipe output, considering the combined system of the fuel, engine, and after-treatment devices. The 4SDI technical team also quantified emission targets for the engine alone: 0.36 g/mile for NOX and 0.04 g/mile for PM.
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From page 25... ...
i 0.02 0.01 0.01 Fuel economy penalty due to emission control system (%) <5 <5 <5 aRatio of mechanical power out to fuel energy rate (lower heating value)
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From page 26... ...
and fuel compositionengine interactions, and investigations of variable valve actuation and variablecompression-ratio systems. The challenges are many and great; however, if successfully developed, these combustion approaches could be integrated into a more conventional engine-operating scheme to improve emissions and fuel economy, but probably not for the 2004 time frame.
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From page 27... ...
The 4SDI technical team believes that the major breakthrough in conversion efficiency needed to make them viable is unlikely in program's time frame. The highest NOX conversion efficiency and the least fuel economy penalty have been achieved using an SCR system with urea as the reductant.
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From page 28... ...
The 4SDI technical team estimates that this fuel economy penalty would be approximately 5 percent. Adding a sulfur trap would extend the lifetime of current NOX traps.
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From page 29... ...
PM reduction strategies include fuel injection optimization, regenerative particulate traps, and fuel and lubricant modifications, which will be discussed below in the "Engine-Fuel Interactions" section. The degradation of fuel economy, as well as the expense, is a concern for all these
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From page 30... ...
In an effort to move closer to practical demonstration of the different after-treatment systems and to address the issues of integrating them into the entire power-train system, the 4SDI technical team is performing integrated power-train vehicle testing. Two different research vehicles fitted with experimental after-treatment systems, particulate traps, and a NOX absorber or urea SCR system are being tested on a special low-sulfur fuel (4 ppm sulfur)
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From page 31... ...
Partnership efforts included auto and oil company ad hoc test programs; the Advanced Petroleum-Based Fuel-Diesel Emission Control (APBF-DEC) program; an ultra-clean fuels initiative; a Coordinating Research Council Advanced Vehicle/Fuel/Lubricants committee; the CARB fuel cell fuel program; and EUCAR (European Council for Automotive Research and Development)
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From page 32... ...
The energy companies participating in the ad hoc program are BP-Amoco, ExxonMobil, Shell, Marathon-Ashland, Citgo, and Equilon. In the program each of the USCAR partners tested four fuels in their own PNGV CIDI engines.
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From page 33... ...
emission standards without extensive after-treatment. Consequently, Phase 2 of the program, in which the fuels are tested in a power-train system that includes after-treatment, is very important.
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From page 34... ...
Since the APBF-DEC program is just getting under way, no technical results are available for evaluation. The mission of the APBF-DEC program is to identify optimal combinations of fuels, lubricants, diesel engines, and emission-control systems to meet continually decreasing emission standards, while maintaining customer satisfaction.
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From page 35... ...
In the pre-competitive cooperative programs, the diesel engine continues to be the focus of research as the desired power plant for the PNGV program. It offers the potential for the best fuel economy with the most realizable near-term manufacturability.
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From page 36... ...
The PNGV should continue the aggressive pursuit and development of lean-combustion exhaust-gas after-treatment systems. The PNGV should also work to develop a detailed systems-modeling effort to quantify the fuel economy penalty associated with using different technologies to meet the emission standards.
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From page 37... ...
An onboard "gasoline" fuel processor, for example, can reduce energy conversion efficiency as much as 10 to 15 percentage points, thus reducing (or even eliminating) the efficiency advantage of a fuel cell over an internal combustion engine.
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From page 38... ...
With pressurized hydrogen, most of the vehicles had diminished passenger compartments or trunk space, primarily to accommodate the volume needed for hydrogen storage. A few of the modified production vehicles, like the International Fuel Cells (IFC)
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From page 39... ...
The significance of this is that, even though industry fuel cell developers appear to have reached a self-sustaining level of activity, the adaptation of fuel cells to automobiles would probably be on a much longer time scale without the PNGV efforts. Program Status The Year 2000 and Targets Early in the PNGV program the year 2000 was chosen as a major milestone year for fuel cell technology development.
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From page 40... ...
The Year 2000 Status and Progress Toward Targets As reported by the Fuel Cell Technical Team, the only year 2000 target that was achieved for the complete integrated gasoline fuel cell system was in the area of emissions; however, just operating the integrated gasoline fuel cell system successfully in 2000 must be considered an important event. Prior to 2000 the gasoline fuel processor and the stack sub-system were developed separately and then operated together, but controlled separately, to demonstrate the capability to operate on gasoline reformate (and other hydrocarbon fuels)
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From page 41... ...
However, the year 2000 PNGV concept cars of Ford, GM, and DaimlerChrysler are HEVs with turbocharged diesel engines. Hybrid-electric vehicle engines operate much closer to peak efficiencies on average than do nonhybrid vehicle engines and probably yield average engine efficiencies also in the mid-30s (in percent)
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From page 42... ...
DaimlerChrysler in Germany has successfully integrated a methanol-fueled fuel cell energy converter with fuel processor into the small A-Class vehicle without infringing on passenger or storage space. This Necar 5 was shown publicly in early 2001 and is now undergoing testing.
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From page 43... ...
The committee's sixth report addressed the PNGV targets for energy storage systems and reviewed NiMH and Li-ion technology development against these targets, with the general conclusions that, despite significant progress, calendar life, cost, and safety remained concerns for Li-ion technology, which is receiving the bulk of PNGV' s battery R&D funds (NRC, 2000~. Nickel metal hydride HEV batteries have not quite met performance targets, and, as with Li-ion batteries, projected costs have exceeded targets by about a factor of three.
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From page 45... ...
The program is overseen by PNGV's Electrochemical Energy Storage (EES) Technical Team, which represents diverse talents and can draw on the extensive knowledge and resources of the participating automobile manufacturers and federal organizations, primarily DOE and its national laboratories.
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From page 46... ...
polymer battery technologies recently added to the PNGV program. These advanced batteries, too, meet the performance targets for the powerassist HEV application; in the case of Avestor's lithium polymer battery, performance targets are also met for the dual-mode HEV application.
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From page 47... ...
Assessment of the Program Several dimensions are relevant when assessing PNGV's electrochemical energy storage and battery program. First, the core of the program consists of well-organized and technically managed development activities centered on the most promising battery systems at several leading developers.
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From page 48... ...
Even allowing for savings due to their lower-power design, dual-mode batteries are likely to cost at least $1,000 to $1,500 per battery unit, or $670-$1,000 per kWh of available energy. Thus, although most technical aspects of PNGV's battery development program have been progressing satisfactorily, prospects for reaching the newly defined 15-year life targets and the cost targets for both power-assist and dualmode HEV batteries would appear slim, even with continued, significant improvements of the mainstream Li-ion and NiMH materials and manufacturing technologies.
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From page 49... ...
In this context the committee notes that the pre-prototype HEV batteries used in the PNGV concept vehicles use battery technologies developed in the PNGV program or, in one case (ArgoTech LIP battery) , in the United States Advanced Battery Consortium (USABC)
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From page 50... ...
To these targets, PNGV should add targets that, if met, make the program's battery technologies viable choices for limited, nearer-term applications, similar to the midterm targets adopted by the United States Advanced Battery Consortium for battery electric vehicles. POWER ELECTRONICS AND ELECTRICAL SYSTEMS All the advanced vehicles being developed under the PNGV program are variants of an HEV.
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From page 51... ...
Except for one of the contractors, the hardware displayed was not far removed from the conceptual stage. The BE Tech Team has required each contractor to execute a detailed costgap analysis in collaboration with suppliers to address four issues: 1.
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From page 52... ...
To monitor progress toward these targets, the BE Tech Team should require its gap analysis to be updated on a regular and frequent basis. The AEMD contractors are Lynx/Delco Remy and Delphi.
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From page 53... ...
During the last few years, however, the purity of the material has been improved by nearly an order of magnitude and costs have been reduced to approximately $20 for 2-inch wafers. The technology has been licensed to Vishay, and the BE Tech Team has proposed that the DOE fund continued development.
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From page 54... ...
The electronics and electrical systems technical team should assure that there is effective communication between the automotive power module (AIPM) and automotive electric motor drive (AEMD)
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From page 55... ...
Body 1,134 566 50 BIWa 590 Chassis 1,101 550 50 Power train 868 781 10 Fuel/other 137 63 55 Curb weight 3,240 1,960 40 aBody-in-white (BIW) includes all the structural components of the body, the roof panel, and the subframes, but not the closure panels.
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From page 56... ...
(2,385 lb) Body structure N/A LIMBTbon Aluminum Aluminum aluminum space frame unibody space frame & panels, and CFRPCsheet aFuel economy is in miles per equivalent gallon of gasoline.
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From page 57... ...
targeted to have an overall length of 187 in (4,750 mm) and a total weight of 2,275 lb when powered by a gasoline-fueled internal combustion engine (ICE)
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From page 58... ...
, the committee believes that, based on its own knowledge of worldwide matenals developments and extensive benchmarking conducted by the PNGV matenals technical team in preparing the matenals roadmap, it is very unlikely that the PNGV effort is likely to be blindsided by a new matenals technology. While weight savings have been a prime consideration in choosing R&D work, programs aimed at reducing the cost of low-density matenals are a major part of the project portfolio.
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From page 59... ...
A polymer composite truck pickup box was developed by liquid composite molding, resulting in a weight savings of 27 percent for the complete assembly (see Figure 2-2~. A cost model was developed that shows that the composite pickup box is lower in cost relative to steel for target volumes in the range of 50,000 to 75,000 units, as shown in Figure 2-3.
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From page 60... ...
-6% PARTNERSHIP FOR A NEW GENERATION OF VEHICLES Box Inner Box Assembly 50 75 / 1 00 1 25 Annual Volume (thousand units) FIGURE 2-3 Cost of polymer composite pickup box relative to the cost of steel pickup box.
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From page 61... ...
The steel counterpart was 30 percent heavier and composed of 40 separate parts. Another approach to composite body technology is being pursued by DaimlerChrysler in its proprietary PNGV program (NRC, 1999, 2000~.
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From page 62... ...
Program Assessment As the PNGV program moves toward 2004 and the requirement of producing affordable production-prototype vehicles, the PNGV team should attempt to balance the opposing requirements of weight reduction and affordability. The arguments presented in the "Materials Selection, Design, and Manufacturing" section above lend credence to this position.
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From page 63... ...
The Goal 3 safety requirement in the 1995 PNGV Program Plan was to meet all Federal Motor Vehicle Safety Standards (PNGV, 1995~. Since 1995 consumer choice has shifted to heavier vehicles that also are perceived to provide increased safety.
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From page 64... ...
The results will provide NHTSA research information to assist in a possible upgrade to FMVSS 111. The 1995 PNGV Program Plan calls for NHTSA involvement to "help assure that any vehicles offered for sale possess structural integrity, include occupant protection systems, and do not compromise safety levels" (PNGV, 1995~.
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From page 65... ...
HEV power trains (power electronics, energy storage)
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From page 66... ...
Program, as well as efforts through the CARE Fuel Cell Program, and EUCAR/USCAR Cooperative Fuels Research (see Chapter 2 section, "Internal Combustion Reciprocating dinginess. The primary power plant options under consideration in the PNGV are the CIDI engine in the HEV configuration and fuel cells; the fuel implications of each of these are discussed below.
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From page 67... ...
As addressed in the section "Internal Combustion Reciprocating Engines" in Chapter 2, fuel composition can impact the production of regulated emissions, most notably PM and NOX. It has been concluded that, even under the most favorable conditions, the reduction of in-cylinder emissions is not sufficient to preclude extensive exhaust-gas after-treatment.
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From page 68... ...
Fuels for Fuel Cells While some work has been initiated on the direct methanol fuel cell, the PNGV has focused primarily on the hydrogen fuel cell with a gasoline fuel processor to provide the hydrogen. The program also includes some work on a flexible-fuel processor as well as distributed hydrogen generation at service stations, combined with onboard storage of hydrogen.
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From page 69... ...
A multiyear program (DOE, 2000b) to address these issues and to explore the use of reformulated diesel, methanol, ethanol, and Fischer-Tropsch liquids in fuel-flexible fuel processors is under way.
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From page 70... ...
, if the use of MTBE in gasoline decreases, more methanol could become available without new plants. It is clear from the foregoing discussion that the hydrogen required by fuel cells could be generated from gasoline, another petroleum liquid fuel, methanol, or natural gas.
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