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F Letter Report: Technology and Economic Analysis in the Prepublication Version of the Report Effectiveness an`/ impact of Corporate Average Fuel Economy (CA FEJ Stan~lar~ls Hi' C>240 t4.5 ~~5~20f'55 tiff2,~f ~ `. ~ . 5 all . I) ~ ,, i, ~ ., . ~ ~ ' ~ y ~ 2 ~ x):, . ~ .) 5; I'm t`~5~c494~{,,f'~;',55i ';C'~V 5''5'',~)7~t=~^2l.~' -I'm 'it |~-'t5~35~-, <3'~\,461~35~:Ji;C'.,',... 2~'C --45t, j f'532' 86 ~;~53 -ala t 5~ . ~ ~.~ ~~ ~ t f'i''~e l.~ j~iS'`~\ \\r~ ~~t')~0 ^~) ~ `) 2 $tft~f~ 0ft']~] ~~ ll<~0 5~\ \~5'tt~0 Con ~ TV ~~ ~ ~ ,)54~'l~'0t 0t i~] 4~t S\\r Room532~) Of 06~(') ]af'lus<~S I,4~t,)~2 Low Dr. ~~gi~o I, 3~ p}~62~6 t~ 60~.],~t t~.3 lift t0~ t~ )~ Lt ~~5~f~f~25 I'll ~540~7 aid to Is t~0 p0~]f.~543] ~t iUCl ~2~0m\/ g~5~, }~ t~0 ~~8l ~54280~ 0~< {l ({'~) 5t^~ ~i'~/'~62 2'00~. ~ ~ ~ ~ ~ ~ ~ ~ f ~ ~ ~ ~ ~ ~ ~ ~ ~ if ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ i ~0 ~2 5~; 5 ~ ~ ~ ~ \~' ~ f ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ( ) ~ ~ ~ ~ ~ ~ ~ ~ Cal i' ~ ~ t ~ 2W ~ ~ ~ ~ ,l it. ~ ~ ,l ) \~ ~ 6 ~ ~ ] 0 ~ ] ~ ~ ~ ~ 8 ~ ~ 0 ~ ~ 0 ~~ ~ ~ ~~ t ~ ~ t l] ~ t ~ ~ ~ ~ t ~ 5C~ 6 0 ~ ~ ~ ~ \~ ~ ~ tu r:~a ~ ~t ally h 3~\ ed l )~ tCtt~t [Cp'0~ 00~5 6~5f th~ t)~0 .~.~]f.0450~.~\ ~ 9u S.~0 \ all6 S t}~ 00~ t~ p(~ t~ 0~ (~ 000~] t~ :~0 lt~ ~8258 ~2f~ tl)0 cstimates are 28~76t> 4~t, 50t th0 0000h~ 5~S (~0fitf.65~2~ 3~0 082~.f~> ~ ~ >v ~ ,~6 ti,~e rel'i'S2']0n)~2:~5 (~f2~]S] l~02l f~'p0~$ it30~0 t~0 (.i;~j rcport w~y0t \~7~ ~Y57900t t~ 60~-2\S0t 6)r ~t tl)~ ~] ~{ ]'`~t'ft3~ WCC p]~ to (~2~35C~ t}~8 ]~t[~=[ [~ to t)~ p026~0 at t)C200 3~m 00 \~64~02845~Y j~ ~ ~ ^t tt~ t]~3' - 00~5 W]~] 8~0 60 ]~~ 6~-~7;~0 t~ ~8 (~0ftt~, ~.] t5~ (~4 ~.~) 60 p03~] 0~32 tt.~ ~6~{ ^~02.~.~8 \,\;~2:6 28~> 133

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134 EFFECTIVENESS AND IMPACT OF CORPORATE AVERAGE FUEL ECONOMY (CAFE) STANDARDS or i4' 2002 ~4 ~40 Research COunCti.~! A.c ~ A ~ ~ ~ my ~ 8~ t\{ ~ 6~] ~ ~ ~ ~ ~8 202~:42 .~ ~ ~ ot :.

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APPENDIX F Technology and Economic Analysis in the Prepublication Version of the Report Effectiveness and Impact of Corporate Average Fuel Economy (CAFE) Standards This letter report summarizes the reexamination of several technology issues originally presented in the prepublication report by the Committee on the Effectiveness and Impact of Corporate Average Fuel Economy (CAFE) Standards. It first explains WhY the reexamination . . . . .. ~ . . .. ~ ~ was undertaken and the process for doing so. it then evaluates the methodology used in Chapter 3 of the prepublication version of the report for estimating the benefits of improved technolo~v. corrects several minor errors, and explains the results. In doing so, it stresses the committee s desire that readers focus on averages! estimates for cumulative gains and costs instead of the upper and lower bounds, which reflect the increasing uncertainty of costs and benefits as fuel efficiency is increased. It also updates and explains the economic analysis presented in Chapter 4 of the prepublication version. ~ lo,, .. . . ~ ... . REASONS FOR THIS LETTER REPORT At the request of the U.S. Congress, the National Research Council (NBC) released a prepublication version of its report Effectiveness ant! Impact of Corporate Average Fuel Economy (CAFE) Standards in July 2001. The committee prepared the report in less than 6 months because Congress expected to aciciress CAFE standards in 200 1 ant} had requested guidance on technical feasibility. During the study, President George W. Bush announced that this report would be an important factor in his energy policy, prepared uncler the direction of Vice President Richard Cheney. During this initial 6-month period, the committee held a series of public meetings at which representatives of automobile manufacturers, governmental agencies, and a variety of nongovernmental organizations provided information on the issues addressed in the report. The committee also visited! manufacturers and major suppliers, reviewed thousands of pages of presentation and other background material, and retained consultants to provide detailed analyses. Following the release of the prepublication report, the automotive industry challenged some of the estimates for improved fuel economy. Representatives of the Alliance of Automobile Manufacturers (AAM), General Motors, and DaimierChrysTer told the NRC in August 2001 that, in their opinion, portions of the technical analysis in Chapter 3 were fundamentally flawed! ant! that some of the estimates for fuel economy improvements violated the principle of conservation of energy. In particular, the industry claimed that the method used to estimate incremental improvements in fuel consumption through stepwise application of technologies did not consider system-level effects and that "double-counting" of potential reductions in energy losses had occurred, especially in upper bound estimations which resulted in the violation of the first law of thermodynamics (conservation of energy. t The largest energy loss is due to inefficiency of the engine. The maximum efficiency of a typical current spark-ignition engine is about 35 percent. The remainder of the energy in the fuel is transferred to the atmosphere as thermal energy in the exhaust or through the cooling system. Some of the technologies discussed here raise efficiency, but in general it is difficult to significantly reduce these losses. Other technologies indirectly accomplish 135

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136 EFFECTIVENESS AND IMPACT OF CORPORATE AVERAGE FUEL ECONOMY (CAFE) STANDARDS In response to these concerns, especially in light of the potential impact of the report's findings and recommendations on national energy policy, the committee held a public meeting on October 5, 2001. Industry representatives and several analysts with other perspectives presented their questions and concerns about the report.2 The presentations are available in the NBC's public access file. In addition to the allegation of violating the principle of conservation of energy, industry raised other issues including the following: 1. Some technologies are already in widespread use, so the improvement from implementing them for a particular class of vehicle is minimal. 2. Improvements from some technologies are overstated. 3. Baseline fuel economy levels do not match Environmental Protection Agency (EPA) data. 4. Some data supplied to the committee may have been misinterpreted as based on fuel consumption rather than fuel economy, leading to an overstatement of benefits. Because of these errors, the break-even analysis in Chapter 4 overestimates the benefits of raising fuel economy standards. Feng An presented some of the results from a recent report by the American Council for an Energy Efficient Economy (ACEEE) and commented on the automotive industry's presentation. He pointed out that the ACEEE analysis, which was based on detailed energy balance simulation, predicted results similar to those in the committee's report when weight reduction was excluded. He also noted that industry's treatment of engine idle-off was inaccurate and that analysis of energy losses was a matter of engineering judgment as well as exact mathematics. He concluded that some double-counting of benefits may have occurred in the committee's most optimistic estimates. However, he argued that two other factors counter this problem. First, other technologies could reasonably have been included by the committee, especially weight reduction and hybrid-electric vehicles. Second, combining technologies can produce positive synergies,3 which may not have been considered. David Friedman stated, among other things, that the committee had clearly eliminated most double-counting, and, insofar as some may have occurred, the committee could have considered additional technologies to achieve the same or greater levels of fifed economy. He this goal; e.g., friction reduction results in less heat transfer from the radiator. Many of the engine technologies discussed here typically are applied to reduce pumping losses (the energy required to move the air for combustion through the engine), a smaller loss but one easier to reduce. As these technologies are added, pumping losses decline, reducing the potential for the next technology. If these diminishing returns are not considered, the analysis may overpredict the reduction in pumping losses, resulting in double-counting. However, many of these technologies have secondary benefits as well, which also must also be considered. The term "system-level effects" refers to these interactions. 2Formal presentations were made by Greg Dana of the Alliance of Automobile Manufacturers; Feng An, a consultant working with the Energy Foundation and the American Council for an Energy Efficient Economy; and David Friedman of the Union of Concerned Scientists. Accompanying Mr. Dana were Aaron Sullivan of General Motors (who made an additional informal presentation), Tom Asmus of DaimlerChrysler, Tom Kenny of Ford, and Wolfgang Groth of Volkswagen. In addition, Barry McNutt of the Department of Energy made an informal presentation. 3System-level effects can be positive as well as negative. The term "synergies" is used when the benefit is greater than the sum of the individual contributions.

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APPENDIX F believed that with those technologies, even the most optimistic upper bound could be achieved. He noted that losses due to aerodynamic drag, rolling resistance, and inertia can easily be reduced more than the committee had allowed, and probably at lower cost than some of the technologies that are on the committee's list. In abolition, hybrid electric vehicles (HEY) may become competitive faster than the committee had assumed, and positive synergies were not always included in its analysis. The committee, in particular the Technology Subgroup,4 examined the concerns expressed at the October 5 public meeting, reviewed acIditional materials submitted by interested parties, evaluated the potential for fundamental errors in its original analysis, and wrote this report to present its findings. This effort has been limited to the technology methodology an.' .. . - presented in Chapter 3 of the prepublication version ant! the potential impact any revisions would have on the economic analysis in Chapter 4. The review uncovered several minor computational or data entry errors in the original analysis. These are identified here and corrected in the final CAFE report, scheduled for publication in early 2002. In addition, the methodology used for estimating the fuel efficiency improvements is explained in greater detail, as is the increasing uncertainty in upper and lower ) sounds in the prepublication version of the report. These bounds have been eliminated in the final report and in this letter report in order to help focus the reader on the average estimations. FINDINGS Based on its review of the information provicled to it subsequent to the July 2001 release of the prepublication version of the CAFE report, in combination with additional investigations conducted by the Technology Subgroup, the committee finds as follows: . The fundamental findings ant! recommendations presented in Chapter 6 of the CAFE report are essentially unchanged. The committee still finds that "technologies exist that, if applied to passenger cars and light-duty trucks, would significantly reduce fuel consumption within ~ 5 years" and that "assessment of currently offered product technologies suggests that light-duty trucks, including SWs, pickups, and minivans, offer the greatest potential to reduce fuel consumption, on a total-galilons-savec} basis." The only changes to the finclings ant! recommendations presented in the prepublication version are the references to the analyses presented in Chapters 3 and 4, which have been modified as discussed in the section "Technical Discussion," below, and Attachments A through E. Baseline fuel consumption averages have been reviser! to reflect the latest results published by EPA for mode} year 1999. The technology matrixes have been modified to eliminate unlikely combinations that were erroneously camed forward in the spreadsheets (see Tables 3-l to 3-3 in Attachment A). Calculations of incremental reflections in fuel consumption for certain vehicle ciassesS also have been corrected. 4John Johnson, Gary Rogers, Phillip Myers, and David Greene. Midsize and large cars should have used camless valve actuation instead of intake valve throttling in path 3. The benefits of variable valve timing should have been 2-3 percent (instead of 1-2 percent) and variable timing and lift should have been at 1-2 percent (instead of 3-8 percent). 137

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138 EFFECTIVENESS AND IMPACT OF CORPORATE AVERAGE FUEL ECONOMY (CAFE) STANDARDS These changes had a mixed effect on fuel economy estimates, but the net result is to slightly lower the averages. In addition, the upper and lower bounds in Table 3-4 and Figures 3-4 to 3-13 of the prepublication version have been removed (see Attachment A). The greatly increased uncertainty as technologies were added caused considerable confusion, and the committee decided to simplify the presentation. The economic analysis has been modified to reflect these changes and several other minor modifications, as discussed in the section "Analysis of Cost-Efficient Fuel Economy Levels," below, and shown in Attachment B. These changes, which are incorporated into the final CAFE report, had no significant impact on the overall findings and recommendations of the report because the average estimates changed so slightly. The committee notes that its analysis of the incremental benefits of employing additional fuel-efficient technologies was, of necessity, based largely on engineering judgment. A detailed energy balance simulation of all the technologies in all the vehicle classes could potentially improve the accuracy of the analysis, but that task was well beyond the resources of the committee. The prepublication version of the report states, "Within the time constraints of this study, the committee used its expertise and engineering judgment, supplemented by the sources of information identified above, to derive its own estimates of the potential for fuel economy improvement . . . ." The report also notes that "the committee has applied its engineering judgment in reducing the otherwise nearly infinite variations in vehicle designs and technologies that would be available, to some characteristic examples." Moreover, as confirmed during testimony presented by AAM representatives, the committee did not have sufficient proprietary technical data to conduct highly detailed simulations. Additional explanation of this estimation process is presented in the "Technical Discussion" section, below. 4. The committee acknowledges that, although it was conservative in its estimates of potential gains attributable to individual technologies (in an attempt to account for potential double-counting), some overestimation of aggregated benefits, compared to aggressive development targets, may have occurred in paths 2 and 3 in the prepublication version. Nevertheless, the committee finds that the principle of conservation of energy was not violated. Furthermore, the committee may have underestimated some potential improvements and given insufficient consideration to system-level synergies. The committee conducted a more detailed simulation to determine whether significant overestimations of potential benefits may have inadvertently occurred. Only one case (midsize SWs) was considered in the time available, but this case provides a general confirmation of the methodology used in the CAFE report. This analysis (cletailed in the technical discussion and in Attachment C), shows that the most optimistic upper- bound estimate in the prepublication version exceeded aggressive development targets by less than 1 0 percent. The same analysis suggests that if pumping losses were reduced to extremely low levels (due to unthrottled operation) and Fiction was reduced bv 30 to 40 percent (theoretically possible but not currently feasible for

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APPENDIX F production engines), fuel consumption reductions would equal the most optimistic upper-bound estimate for midsize SUVs in the prepublication version. Therefore the committee finds that its analysis did not violate any laws of energy conservation. The committee acknowledges that the uncertainty associated with any upper boundary increases significantly as additional technologies are considered. Accordingly it does not propose them as development targets. All estimates (even those involving sophisticated modeling) of the costs and benefits of new technologies are uncertain. As technologies are added, the overall uncertainty increases. The committee included a wide range of costs and benefits for each technology to account for such uncertainties. However, based upon the feedback received since the release of the prepublication version, the committee believes that the increasing level of uncertainty associated with moving up each of the three paths was not sufficiently explained in Chapter 3. Additional technical discussion and clarification are therefore included below. Furthermore, the committee finds that its methoclology for determining the collective uncertainty as technologies are added has produces! wide upper- ant! Tower-bounc! estimates that have contributed to confusion and misinterpretation of the analysis. Chapter 4 uses a statistical technique to narrow the bouncis (using the values for each technology in Chapter 3 as input), as seen in Figures 4-5 and 4-6 in Attachment B. This technique maintains an approximately constant confidence bound over the range of fuel economy. Therefore, the upper and lower bounds for improved fuel consumption and associated costs are dropped from Table 3-4 and Figures 3-4 to 3-13 (see Attachment A), and only the now slightly lower averages are retained in order to focus attention on the most probable and useful results. However, the reader is cautioned that even the averages are only estimates, not exact predictions. CONCLUSIONS Based on the additional information provided to the committee subsequent to the July 2001 release of the prepublication version of the CAFE report, including testimony provided at the October 5, 2001, meeting, the committee concludes as follows: I. The committee reaffirms its approach and general results: Significant gains in fuel economy are possible with the application of new technology at corresponding increases in vehicle price. Although the committee believes that its average estimates, as presented here, provide a reasonable approximation of the fuel economy levels attainable, it endorses its statement in the prepublication version namely, that changes to CAFE standards should not be based solely on this analysis. Finding 5 of the CAFE report states: "Three potential development paths are chosen as examples of possible product improvement approaches, which illustrate the trade-offs auto manufacturers may consider in future efforts to improve fuel efficiency." The finding also notes that "economic, regulatory, safety, and consumer-preference-related issues will influence the extent to which these technologies will be applied in the United States." ]39

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140 EFFECTIVENESS AND IMPACT OF CORPORATE AVERAGE FUEL ECONOMY (CAFE) STANDARDS 2. The fuel economy estimates include uncertainties that necessarily grow with the increasing complexity of vehicle systems as fuel economy is improved. Thus for regulatory purposes, these estimates should be augmented with additional analysis of the potential for improvements in fuel economy and, especially, their economic consequences. The development approaches that manufacturers may actually pursue over the next ~ 5 years will (1epend on improvements made in current systems, price competitiveness of production-intent technologies, potential technological breakthroughs, advancements in diesel emission-control technologies, and the quest for cost reduction in hybrid technology. Path 3 includes emerging technologies that are not fully developed and that are, by definition, less certain. The committee also recognizes that this path includes technologies that likely have not been tested together as a system. The upper and lower bounds of the paths are even more uncertain than the average. Therefore in formulating its conclusions, the committee used the path averages. Full analysis of systems effects, which might be better definer! by more rigorous in(lividual vehicle simulations, could suggest fuel economy improvements that are greater or less than the average estimates made by the committee. More accurate estimates would require detailed analyses of manufacturer-proprietary technical information for individual vehicle models, engines, transmissions, calibration strategies, emissions control strategies, and other factors information to which the committee has no access. Even if such information were provided, evaluating all possible scenarios would require a prohibitive number of simulations for the committee to pursue. 3. Based on input provided subsequent to the July 200 ~ release of the prepublication version, the committee concludes that additional technologies, beyond those iclentifiec} in the report, may also become available within the ~ 0-] 5 year horizon. The committee may have underestimated the vehicle-based (e.g., aerodynamics, rolling resistance, weight reduction) benefits that may be expected within ~ 5 years. Prototype vehicles are now being designed and tested that achieve significantly higher fuel economy (FE) than the levels considered by the committee (see the section "Future Potential," in Attachment D). While the committee has not analyzed all of these concepts (they still must surmount a series of banners, including cost, emissions compliance, and consumer acceptance issues), it notes that they illustrate the technical potential for greater fuel economy. 4. At the August 2001 meeting, industry representatives stated that the methodology used by the committee violated the principle of conservation of energy.6 However, at 6The industry representatives separated the technologies according to how, in their judgment, they might reduce energy losses. They expected most technologies to contribute to reducing pumping and engine friction losses. When they added all the improvements from those technologies, the total exceeded some relative value assumed to represent the combined EPA city/highway cycle for a single vehicle example. This was the basis for the claim that

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APPENDIX F the October 2001 meeting, no detailed energy balance formulations or indepenclent analyses were presented to support this claim. Rather, industry representatives presented their judgment-based contributions of the different technologies considered by the committee to reduce energy losses. The representatives then summed these contributions, suggesting that the committee's methodology overestimates the potential improvement and thereby violates the conservation of energy principle. The committee has several points of contention with industry's formulation of the energy balance issue: for example, the allocation of the benefits of an integrated starter-generator (with idle-ofi~ to pumping, friction, ant} transmission. While turning off the engine when power is not needled (i.e., during idle or braking) does not raise the efficiency of the engine itself, it does lower the energy required for the EPA test cycles used to measure fuel efficiency. Thus idle-off effectively results in an increase in overall fuel economy, which can be realized without violating the conservation of energy. This effect varies the relationship between engine losses and fuel consumption that has historically been considered when estimating fuel economy. Regenerative braking, although not considered in the three hypothetical paths, is another example of fuel economy improvement being essentially independent of ^, ~ engine ettlclency. In addition, assumptions as to primary and secondary benefits must consider varying trade-offs as many new technologies are aggregated. The committee therefore concludes that differences in engineering judgment are likely to produce significantly different approximations when projecting some ~ 5 years into the future. The committee agrees that achieving the most optimistic (upper bound) results of path 3 in the prepublication version of the report with the technologies iclentified there wouIc} require overcoming great uncertainty and technical risk. The committee did not regard the upper bound as a viable production-intent projection. It is a bound, by definition, as is the lower bound, and plausible projections lie somewhere in between. Furthermore, consumer acceptance and real-worId characteristics will certainly cause actual fuel economy gains to be less than the technically feasible levels presented in this stiffly. 5. The committee reaffirms its position in Fincling 6 of the CAFE report: "The committee cannot emphasize strongly enough that the cost-efficient fuel economy levels identified in Chapter 4 are not recommended CAFE goals. Rather, they are reflections of technological possibilities, economic realities, and assumptions about parameters values and consumer behavior." The fuel economy estimates in Chapters 3 and 4 describe the trade-offs between fuel economy improvement and increased vehicle price. They do not incorporate the value of reducing U.S. oil consumption or greenhouse gas emissions. Nor are they based on particular views of the the NRC analysis violates conservation of energy. The presentation, but not the specific charge, was repeated at the October meeting, yet the detailed propriety data behind the relative assumptions were not offered. 141

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142 EFFECTIVENESS AND IMPACT OF CORPORATE AVERAGE FUEL ECONOMY (CAFE) STANDARDS appropriateness of government involvement. The committee provides some discussion of these issues, but the value judgments must be left to policy makers. TECHNICAL DISCUSSION Methodological Issues The state of the art in overall powertrain simulation, including gas exchange, combustion, heat loss, exhaust energy, and inclicated thermodynamic efficiency, has advanced with the development of computing capacity, computational fluid dynamics, and mechanical system simulation. Automotive manufacturers, subsystem suppliers, private and governmental research institutions, and universities around the world are investing vast resources to improve the accuracy of such predictive tools. Expansion of the simulation to include the transmission, drivetrain, tires and wheels, vehicle aerodynamics, rolling resistance, frictional losses, accessory loads, and the influence of control system response, calibration strategies, and hundreds of other parameters creates models of sufficient size to tax even high-power computers. Morever, such sophisticated models still require experimental verification and calibration and are best used to quantify incremental improvements on individual vehicle models. They also require the input of proprietary data. The committee's charge was to estimate the potential for fuel economy improvements, not to define new regulatory standards. Hence it clesired only a general understanding of the potential for fuel economy gain for different types of vehicles and what the relative costs might be. In aciclition, the committee wished to determine Which technologies are currently being applier! in markets where the high price of fuel provides an economic incentive for the introduction of new technology for reduced fuel consumption. Although the committee is familiar with the state-of-the-art analytical methods identified above, it slid not have the resources, time, or access to proprietary data necessary to employ such methods. Therefore it used a simpler methodology to provide approximate results. The committee identified candidate technologies, as explained in Chapter 3 of the prepublication version of the report, that could be considered for application in various types of vehicles. It then estimated ranges of possible improvements in fuel consumption and costs associated with these technologies. Finally, it assembles! packages of technologies, deemed revelant to different vehicle classes, and estimated the total impact on fuel economy and costs. This approach allowed the committee to estimate potential changes in a wide variety of vehicle classes within the boundary conditions of the study. The committee notes that similar methods were used in the ~ 992 NRC analysis of automotive fuel economy potential (NRC, 1 992) and by many studies in the published literature over the past 25 years (see, e.g., Greene and DeCicco, 2000, for a review). Analytical Issues Technical input to the study included a review of technical publications, a review of automotive manufacturer announcements of new technology introductions and reported fuel consumption (economy) benefits, and information acquired directly from automotive manufacturers and suppliers in the United States and abroad. The committee evaluated vehicle

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APPENDIX F features (engine size, number of cylinders, state of technology) and published performance and fuel economy data. It assessed engine, transmission, and vehicle-related energy consumption, system losses, and potential improvements in thermal or mechanical efficiency. Finally, the committee applied engineering judgment to reduce an exceedingly complex and seemingly infinite number of possible technology combinations and their relative performance, fuel consumption, dnvability, production costs, and emissions compliance trade-offs into a more manageable, though approximate, analysis. Most of the technologies considered in the committee's analysis either are in, or will soon enter, production in the United States, Japan, or Europe. Promising emerging technologies, which are not completely developed but are sufficiently well understood, were also included. Background information concerning these technologies is given in Chanter 3 of the CAFE report. The potential choice of technologies differs by vehicle class and intended use. In addition, the ease of implementation into product plans and consumer-based preferences will influence whether a technology enters production at all. The analysis was complicated by the need to infer potential fuel consumption benefits from published data in which experimental results were based on European (NEDC) or Japanese (10/! mode) test cycles. Furthermore, differences in exhaust emission regulations, especially between European and U.S. Tier TI or California standards, can have a great effect on the potential application of several technologies.7 The potential of each technology to improve fuel economy, and the costs of implementing the technology, were determined Mom the sources listed above. Both fuel economy (FE) benefits and costs are expressed in terms of a range, with low and high values, because of the uncertainty involved.8 The benefit is expressed as a percent reduction of fuel consumption (FC; gallons/IOO miles). The fuel consumption ranges were adjusted in an attempt to account for potential double- counting of benefits. Attachment E shows how FC improvements were modified to avoid double-counting. It also shows that most of the technologies considered have primary and secondary benefits related to the reduction of different types of losses or improvements in thermal efficiency. In general, this strategy results in predicted improvements for individual technologies that are lower than the values commonly found in the literature. In addition, subsequent to the release of the prepublication version, the committee simulated one case, the midsize SUV, in order to evaluate potential inaccuracies in its simplified methodology. This sample simulation is presented in Attachment C. To assist in evaluating near-term potential (within ~ O years) versus long-range predictions (l O- ~ 5 years or beyond), the committee considered three technology paths with three different levels of optimism regarding technology implementation. The technologies grouped within these paths were chosen based on current production availability (in the United States, Europe, or Japan), general compatibility with the dominant vehicle attributes (engine size/power, transmission This is especially true in the case of lean combustion concepts (direct-injection diesel and gasoline), which are unlikely to penetrate U.S. markets rapidly due to production cost and emissions compliance issues, even though they are quickly approaching 50 percent of the new vehicle sales in Europe. The committee examined these technologies but did not include them in any of the paths because of high uncertainty concerning exhaust emissions compliance and production cost. Nevertheless, it is quite possible that one or more will be successful. In such a case, fuel economy levels higher than any of those estimated by the committee could become feasible. ~ Note that the economic analysis in Chapter 4, including that in the prepublication version, heavily weights the average but statistically considers the uncertainty represented by the high and low values. 143

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156 EFFECTIVENESS AND IMPACT OF CORPORATE AVERAGE FUEL ECONOMY (CAFE) STANDARDS l Multivalve, Overhead Camshaft (2V vs. 4V) FC Improvement From Base From Ref. Technology Improvement from 2 valve engine into a multiintake valve engine (including Description total of 3, 4, and 5 valves per cylinder) Primary Benefits Lower pumping losses: larger gas exchange flow area Less friction: higher mechanic efficiency due to higher engine IMEP Secondary Less pumping losses: engine down size with higher power density Benefits Higher thermal efficiency: higher compression ratio due to less knocking tendency and faster combustion process with central spark plug position FC Improvement Base: 2V baseline engine Reference: 2V baseline en-tine 2 ~ 5% 2 ~ 5% . . Example of Advanced engines from Ford, GM, and DC Application | Reference | Volkswagen:R.Szengel,H.Endres | | 11%FCin 6. Aachener Kolloquium (1997) MVEG Conclusion: A 1.4L-14-4V engine improves the fuel consumption by 11% (MVEG) in comparison to a 1.6L-14-2V engine , . ~ _ -ord: D. Graham, S. Gerlach, J. Meurer. SAE-Paper 962234 4 5% FC Conclusion: new valve train design (from OHV to SOHC) with 2 valves per (OHV, 2V to cylinder plus additional changes (higher CR, less valve train moving mass) SOHC, 2V) result in a 28% increase in power, 11% increase in torque and 4.5% +28% power I reduction in fuel consumption (11.2 to 10.7 UlOOkm, M-H) for a 4.0L-V6-2V | | +11% torque engine. Sloan Automotive Laboratory / MIT: Dale Chon, John Heywood SAE-Paper 2000-01-0565 Conclusion: The changing preference from 2-valve to 4-valve per-cylinder is a major factor of current engine power and efficiency improvement; the emergence of variable valve timing engines suggests a possible new trend will emerge.

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APPENDIX F 157 l Variable Valve Timing (VVT) | FC Improvement From Base From Ref. | Technology ~ Variable valve timing in the limited range through cam phase control ~ l Description | Primary Benefits | Less pumping losses i: later IVC to reduce intake throttle restriction for the | I same load Secondary Less pumping losses: down size due to better torque compatibility at high Benefits and low engine speed for the same vehicle performance FC Improvement Base: 2V baseline engine; Reference: 4V OHC en-tine 4 ~ 8 % 2 ~ 3 % . Example of Toyota VVT-i; BMW Vanes Application Reference Ford: R.A. Stein, K.M. Galietti, T.G. Leone 2.8 ~ 3.2% SAE-Paper 950975 V8, 2V engine Conclusion: for a 4.6L-V8-2V engine in a 4,000 lb vehicle benefit in M-H fuel consumption of 3.2% with unconstrained cam retard and 2.8% (M-H) with constrained cam retard (10% EGR) Ford: T.G. Leone, E.J. Christenson, R.A. Stein 0.5-2.0% SAE-Paper 960584 14, 4V engine Conclusion: for a 2.0L-14-4V engine in a 3,125 lb vehicle benefit in M-H fuel consumption of 0.5-2.0% (10-15% EGR) Toyota: Y. Moriya, A. Watanabe, H Uda, H. Kawamura, M. Yoshioka, M. 6% Adachi. SAE-Paper 960579 Japanese Conclusion: for a 3.0L-16-4V engine the VVT-i technology (phasing of intake mode valves) improved the fuel consumption by 6% on the 10-15 official Japanese 16, 4V engine mode. Ford: D.L. Boggs, H.S. Hilbert, M.M. Schechter. SAE-Paper 950089 15% (BSFC) Conclusion: for a 1.6L-14 engine the later intake valve closing improved the 14, Late IVC BSFC by 15% (10% EGR). MAZDA / Kanesaka Tl: T. Goto, K. Hatamura, S. Takizawa, N. Hayama, H 10 ~ 15% Abe, H. Kanesaka. SAE-Paper 940198 Fuel Conclusion: A 2.3L-V6-4V boosted engine with a Miller cycle (late intake Efficiency, valve closing) has a 10-15% higher fuel efficiency compared to natural Miller cycle aspiration (NA) engine with same maximum torque. 25% reduction in friction loss because of lower displacement. Expected 13% increase in fuel consumption of 2.3L Miller engine compared to 3 3L NA engine . v Mitsubis hi: K. Hatano, K. Iida, H. Higas hi, S. Murata. SAE-Paper 930878 Up to 16% in Conclusion: A 1.6L-14-4V engine reached an increase in fuel efficiency up to FC 16% Japanese Test Driving CYcle) and an power increase of 20%. 20% Power ~ . ~ , . Honda/Nissan/ : S. Shiga; S. Yagi; M. Morita; T. Matsumoto; H. Nakamura; Up to 7% T. Karasawa SAE-Paper 960585 Fuel Conclusion: For a 0.25L-11-4V test engine an early closing of the intake Efficiency valve results in up to 7% improvement in thermal efficiency Ricardo: C. Gray SAE-Pager 880386 3 ~ 5/O at part Conclusion: Variable intake valve closing and cam timing duration improves load part load fuel consumption by 3 ~ 5 %

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158 EFFECTIVENESS AND IMPACT OF CORPORATE AVERAGE FUEL ECONOMY (CAFE) STANDARDS l Variable Valve Timing and VariableValveLift(VVLT) | FClmprovement From Base From Ref. Technology Valve lift and valve timing controlled according to engine load and speed, Description with step controlled mechanism Primary Benefits | Less pumping losse ;: partially use intake valve liming and lift control for | l l intake throttle control Higher thermal efficiency: for better mixture formation with intake valve throttling Secondary Less pumping losses: engine down size with higher power density Benefits FC Improvement Base: 2V baseline engine Reference: VVT engine 5 ~ 10% 1 ~ 2 % , , Example of Honda i-VTEC; Porsche Variocam Plus; Toyota VVLT-i Application .. Reference Honda: M. Matsuki, K. Nakano, T. Amemiya, Y. Tanabe, D. Shimizu, 1. 40% more Ohmura SAE-Paper 960583 power with Conclusion: for a 1.5L-14-4V engine the 3-stages VTEC technology (three same fuel different cams) improved the power output by 40% with the same fuel consumption consumption Porsche: C. Brustle, D. Schwarzenthal. SAE-PAPER 980766 3-9% Conclusion: for a B6-4V engine the fuel consumption could be reduced by 3-9% with variable valve lift Meta: P. Kreuter, P. Heuser, J. Reinicke-Murmann, R. Erz, U. Peter. 11% to 15% SAE-Paper 1999-01-0329 at idle Conclusion: For a 2.0L-14-4V engine the VVLT system improved the fuel efficiency by 11% to 15% in idle speed Cylinder Deactivation | FC Improvement From Base From Ref. Technology Deactivate number of cylinders so that the active cylinders work on higher Description BMEP level, normally valve deactivation is necessary PrimarY Benefits The active cylinders have less Dumping loss with higher BMEP level ~ ~ . . Secondary Benefits FC Improvement Base: 2V baseline engine Reference: VVTL engine 8 ~ 16% 3 ~ 6 % . . Example of Mercedes 5.0 L V8 and 6.0 L V12 Application Reference Meta: P. Kreuter, P. Heuser, J. Reinicke-Murmann, R. Erz, P. Stein, U. 6-8% FC in Peter. SAE-Paper 2001-01-0240 NEDC Conclusion: A 14 engine with cylinder valve deactivation (CVD) showed 20% improvement in fuel consumption at low engine speed. A V8 engine showed 6-8% improvement in fuel consumption for the New European Driving Cycle Daimler-Chrysler: M. Fortnagel, G. Doll, K. Kollmann, H.-K. Weining. 6.5% FC in RITZ 98 Sonderheft NEDC Conclusion: A 5.0L-V8-V3 engine has an improvement of 6.5% fuel 10.3% FC in consumption (New European Driving Cycle) and 10.3% in the FTP+HW FTP+HW cycle with the cylinder deactivation

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APPENDIX F 159 Engine Accessorylmprovement I FCimprovement From Base From Ref. Technology | Improving the efficiency of accessory components or their power I ~ ~ Description I transmission to real Ice the engine energy losses l l l Primary Benefits Direct reduction of vehicle fuel consumption Secondary Higher net output allows engine downsizing Benefits FC Improvement | Base: 2V baseline ~ ngine; Reference: 4V OHC engine | 3 ~ 7 % | 1 ~ 2 % | Example of Less coolant flow rate, less oil flow rate Application Reference | "Technology and Cc it of Future Fuel Economy Improvements for Light-Duty | | 0.5 - ~ % | Vehicles - Draft Final Report"; Energy and Environmental Analysis, Inc. - reduction in HAS Report- June 4, 2001 fuel economy Conclusions: Between 0.5 and 1% reduction in fuel economy is possible Supercharging and Downsizing | FClmprovement I From Base From Ref. Technology | Reduce the engine c splacement and supercharge it for the required power | l Descr~pbon Primary Benefits Less pumping loss at low load conditions; less friction power loss at the same FMEP; less Idle losses Secondary | None l l Benefits _ FC Improvement Base: 2V baseline engine; Reference: 4V OHC engine 7 ~ 12 % 5 ~ 7 % Example of Application Reference FEV, Peter Walzer, 00ELE028 Future Engines For Cars 25% Conclusions: Engine down size from 3L to 1.5L with supercharging and at part load, VCR, part load specific fuel consumption improves by 25% with VCR

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160 EFFECTIVENESS AND IMPACT OF CORPORATE AVERAGE FUEL ECONOMY (CAFE) STANDARDS 5-Speed Automatic Transmission | FC Improvement From Base From Ref. Technology | Added ratio places engine in better average speed/load operating point. | l Description Improvements in torque converter lockup via Slip Controlled Converter Clutch. Improved internal oil pump losses by reducing pressure. Closed-loop shift strategy. Reduction of gear drag losses. General weight reduction. Primary Benefits | Less pumping loss at low load conditions; less friction power loss at the l l same FMEP; lower Idle losses Secondary | Improvedtransmissi~nefficiencies ~ l Benefits FC Improvement Baseline: 4-speed; Reference: 4-speed 2 ~ 3 % 2 ~ 3 % Example of Application .. Reference SAE- 970689, "ZF 5-Speed Transmissions for Passenger Cars"; Heribert 5% Scherer, Georg Gierer on combined Auto 2000, "ZF 5-Speed Automatic Transmission"; Heribert Scherer M-H FTP-75 Conclusions: A 5% reduction can be attributed to the new 5-speed transmission Continuously Variable Transmission (CVT) | FC Improvement From Base From Ref. Technology Added ratio places engine in better average speed/load operating point. Description Elimination of torque converter with an optimized starting clutch procedure. Reduced work loss in the drive train and accessories due to the gear ratio characteristics unique to the CVT Primary Benefits Less pumping loss at low load conditions; less friction power loss at the same PREP lower Idle losses . Secondary Improved drive train and accessory losses Benefits FC Improvement ~ Baseline: 4-speed, 1 eference: 5-speed ~ 6 - 1 1 % | 4 ~ ~ % Example of Audi A4- Multitronic Application Reference ~ ATZ 8&9/2000, "Mu itronic - The New Automatic Transmission from Audi - | l Parts 1 & 2" SAE 970685, "ECOTRONIC - Continuously Variable ZF Transmission (CVT);" Manfred Boos and Herbert Dozer SAE 1999-01-0754, "Development of an Engine-CVT Integrated Control 9.3% System;" S. Sakaguchi, E. Kimura, K. Yamamoto on MVEG Conclusions: A 9.3% reduction can be attributed to the CVT transmission

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6-Speed Automatic Transmission I FC Improvement From Base From Ref. Technology | Added ratio places I ngine in better average speed/load operating point. | l l Description Improved gearbox efficiency with outstanding direct drive efficiency and reduced gear drag losses. Improved internal oil pump losses by internally geared wheel-pump and improved volumetric efficiency and reduced leakage losses. Optimized oil supply with reduced leakage in the hydraulic controls and gearbox. Primary Benefits Less pumping loss at low load conditions; less friction power loss at the ~- same FMEP; less idle losses Secondary | Improvedtransmissi in efficiencies I I Benefits FC Improvement Baseline: 4-speed, Reference: 5-speed 3 ~ 5 % 1 ~ 2 % Example of BMW 7-Series Application Reference ATZ 9/ 2000, "6-Speed Automatic Transmission for the New BMW 7- 5% Series;" Wolfgang Hall, Christian Bock on combined Conclusions: A 5% reduction can be attributed to the new 6-speed M-H FTP-75 transmission APPENDIX F 161 Aggressive Shift Logic | FC Improvement From Base From Ref. _ Technology Improvements in torque converter lockup. Descriptions Closed-loop shift control strategy Primary Benefits Reduced transmission losses Second lary None Benefits FC Improvement Baseline: 4-speed Reference: 5-speed 3 ~ 6 % 1 ~ 3 % , Examl ale of Application , Reference | `'Techno~ogyandC(stofFutureFuelEconomylmprovementsforLight-Duty | ~ 9.0-9.3% Vehicles - Draft Final Report"; Energy and Environmental Analysis, Inc. - improvement NAS Report - June 4, 2001 in Fuel Conclusions: A 9%-9.3% reduction can be attributed to aggressive shift logic Economy with a 5-speed transmission

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162 EFFECTIVENESS AND IMPACT OF CORPORATE AVERAGE FUEL ECONOMY (CAFE) STANDARDS l Aerodynamic Drag Reduction | FClmprovement From Base From Ref. Technology | Aerodynamic drag reduction via vehicle shape changes or reduced frontal Descr~pbon area Primary Benefits Reduced higher speed engine load required Secondary None Benefits FC Improvement Baseline: conventional vehicles; Reference: conventional vehicles 1 ~ 2 % 1 - 2 % Example of Application Reference "Technology and Cost of Future Fuel Economy Improvements for Light-Duty 1.6 to 2.2% Vehicles - Draft Final Report"; Energy and Environmental Analysis, Inc. - fuel economy NAS Report- June 4, 2001 reduction Conclusions: A 10% drag reduction is possible with a result in 1.6 - 2.2 % FE reduction. Improve Rolling Resistance | FClmprovement From Base From Ref. | Technology | Reduced bearing, b eke and driveline rotating forces. Improvements in tire | l Description rolling resistances through new tread designs and tire carcass improvements Primary Benefits Reduced engine load required over entire speed range Secondary None Benefits FC Improvement Baseline: conventional vehicles Reference: conventional vehicles 1 ~ 1.5 % 1 ~ 1.5 NO . , Example of Application . . Reference "Technology and Cost of Future Fuel Economy Improvements for Light-Duty 1.6 to 2.2% Vehicles - Draft Final Report"; Energy and Environmental Analysis, Inc. - fuel economy NAS Report- June 4, 2001 reduction Conclusions: A 10% rolling resistance reduction is possible with a result in 1.5 - 2.0 % FE reduction Safety Weightlncrease I FClmprovement I From Base From Ref. Technology Added weight to account for anticipated future safety structure, equipment Description or other features Primary Benefits Increased engine load required Secondary None Benefits FClmprovement | Baseline:conventiol~alvehicles,Reference: conventionalvehicles I 3~ 4% | -3~-4% Example of ADDIication . ~ Reference "Technology and Cost of Future Fuel Economy Improvements for Light-Duty 3 to 4% Vehicles - Draft Final Report"; Energy and Environmental Analysis, Inc. - increase NAS Report- June 4, 2001 Conclusions: 10% weight reduction results in 6.6 to 8% reduction in FE. With a safety weight increase of 5% the committee used 3 to 4% FE reduction to account for this.

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APPENDIX F 163 intake Valve Throbbing FC improvement From Ref. From Base Technology Description Primary Benefits Electronic or hydraulically controlled, mechanically actuated continuous variable valve timing and lift v Less pumping losses: much less, or no, intake throttling for load control. Higher thermal efficiency: better mixture formation with intake valve throttling. Less friction: higher mechanical efficiency due to higher engine IMEP. Less pumping losses: engine down size with higher power density Base: 2V baseline engine; Reference: VVT engine Secondary Benefits FC Improvement . Example of Application Reference 8~16% 3~6% BMW Valvetronic MTZ 10 2001, pp. 826-835 Conclusion: Valvetronic creates a fuel consumption reduction of 12% part load; 20% in idle; 14% reduction of fuel consumption for MVEG 111 compared to its predecessor. Delphi: R.J Pierik, J.F. Burkhard SAE Paper 2000-01-1221 Conclusion: demonstrated brake specific fuel consumption (BSFC) of 12% at idle, 7-10% at low middle load, and 0-3% at middle to high load. 20% idle 12% part load 14% MVEG 111 Idle: 12% low: 7% mid: 10% high: 0-3% (BSFC) Idle: 30% low: 3-4% part load: 5% high: 0% torque: 9.8% Hyundai / Siemens: J. Lee, Ch. Lee, J.A. Nitkiewicz SAE-Paper 950816 Conclusion: For a 2.0L DOHC engine the fuel efficiency could be increased by 30% in idle; 3-4% in low speed; 5% in part load with "lost motion" technology. It uses conventional cam and create lost motion with hydraulic mechanism. . BMW: R. Fierl, M Kluting SAE-Paper 2000-01-1227 Conclusion: The electromechanical valve train offers a reduction in fuel consumption by about 10% plus 5% higher peak torque. Nissan: S. Takemura, S. Aoyama, T. Sugiyama, T. Nohara, K. Moteki, M. Nakamura, S. Hara SAE-Paper 2001-01-0243 Conclusion: A variable actuation system showed fuel consumption of nearly 10% University of Bucharest: N. Negurescu, C. Pana, M.G. Popa, A. Racovitza SAE-Paper 2001-01-0671 Conclusion: For a one-cylinder test engine WT increases the efficiency by 10to29% 0% 10% 1 0-29% efficiency

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164 - EFFECTIVENESS AND IMPACT OF CORPORATE AVERAGE FUEL ECONOMY (CAFE) STANDARDS Cam~ess Valve Actuation FC improvement From Base From Ref. Technology Completely variable valve timing controlled and actuated by electromagnetic Description or high-pressure hydraulic means Primary Benefits Less pumping losses: completely eliminate intake throttling valve for load control Higher thermal efficiency: higher compression ratio with less knocking tendency; better mixture formation with intake valve throttling Less friction: less valve train friction; higher mechanical efficiency due to higher engine IMEP Secondary | Less pumping losses: engine down size with higher power density l l Benefits FC Improvement Base: 2V baseline engine; Reference: VVT engine 10 ~ 20% 5 ~ 10% Example of FEV EMV; Siemens EVT Application Reference FEV: M. Pischinger, W. Salber, F. van der Staay, H. Baumgarten, H. 16% Kemper with EMV FISITA- Seoul 2000 Conclusion: a reduction of 16% fuel consumption can be achieved by using the EMV-technology in a 1.6L-14-4V engine Variable Compression Ratio (VCR) From Base FC improvement . From Ref. 2 ~ 6 onto Technology Description Using higher compression ratio at low load condition for high thermal efficiency and low compression ratio at high load conditions to avoid knocking. Normally applies to supercharged-down size engines. Higher thermal efficiency at part load conditions None Primary Benefits Secondary Benefits FC Improvement Base: 2V baseline engine; Reference: 4V OHC engine and supercharge . . c own slang SMB VCR engine 9~18% Example of Application Reference Saab: H. Drangel, L. Bergsten Aachen Kolloquium 2000 Conclusion: With the combination VCR / high charging and downsizing of the engine, it was possible to get the same power out of an 1.6L-15-4V engine as a 3.0L-V6 engine. The resulting fuel consumption reduction is 30% Daimler-Benz: F. G. Wirbeleit, K. Binder, D. Gwinner SAE-Paper 900229 Conclusion: In a V8 a VCR between 8 to 13.9:1 depending on the engine speed, the fuel consumption improves by 4% to 8% Ford/University of Dar es Salaam: T. H. Ma, H. Rajbu SAE-Paper 884053 Conclusion: At 1,500 rpm and 2 bar BMEP condition, VVT alone achieves . 8% BSFC; WT+VCR achieves 19% 30% 4% - 8% 11 % BSFC (1,500 rpm and 2 bar BMEP)

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APPENDIX F 165 Automated Shift ManualTransmission I FClmprovement From Base From Ref. Technology Improved gearbox efficiency with improved efficiency and reduced gear drag Descriptions losses. Elimination or significant reductions of internal oil pump losses. PrimarY Benefits Improved transmission efficiency- , . , Secondary None Benefits FC Imorovement Baseline: 4-sceed Reference: 6-speed 6 ~ 10 % 3 ~ 5 % . . . Example of Application Reference SAE Toptec- Modern Advances in Automatic Transmission Technology, Estimated "EMAT - Electromechanical Automatic Transmission"; D. Carriere, J. 10% Cherry, R. Reed, Jr. Improvement Conclusions: An estimated 10% improvement in fuel efficiency with in fuel improved performance efficiency Advanced CVT's (Allows Higher Torque) FC Improvement From Base From Ref. Technology | Improved transmiss on efficiency using toroidal-shape and roller elements | l Description and special traction fluids. Permits use in higher torque applications. Primary Benefits Improved transmission efficiency. Brings CVT to higher torque applications. Secondary None Benefits FC Improvement Baseline 4-speed; Reference: CVT 6 ~ 13 % 0 ~ 2 % Example of Application Reference Mazda's Future - Cars and Technology for Tomorrow 20% Conclusions: A 20% improvement in fuel economy in the Japanese 10-15 Improvement mode compared with a current 4-speed automatic transmission in fuel economy

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166 EFFECTIVENESS AND IMPACT OF CORPORATE AVERAGE FUEL ECONOMY (CAFE) STANDARDS Integrated Starter Generator with idle Off | FC improvement From Base From Ref. Technology Integrated starter generator (ISG) cuts off fuel supply at idle and when the Description brakes are applied. Greater starter power enables the engine to be started immediately at higher speed. Primary Benefits Less fuel loss when engine Dower is not necessary , ~ . , Secondary None Benefits FC Improvement Base: 2V baseline engine Reference: 4V OHC engine 6 ~ 12 % 4 ~ 7 % . , Example of Application e ference "Technology and Cost of Future Fuel Economy Improvements for Light-Duty 9 to 11% FE Vehicles - Draft Final Report"; Energy and Environmental Analysis, Inc. - improvement NAS Report- June 4, 2001 Conclusions: Technology will provide for idle off, launch assist, improved power generation with a 9% - 1 1% FE improvement. 42 V Electrical System | FC Improvement I From Base From Ref. Technology | Changing the vehicle operation voltage from 12V into 42V permitting l l l Descriptions electronically controlled thermal management (water pump). Enabling technolonv for 42V ISG. , Primary Benefits Less electrical power losses with less current flow through wires; higher efficiency of the electrical components Secondary Enables higher efficiency ISG systems Benefits FC Improvement Base: 2V baseline engine Reference: 4V OHC engine 3 ~ 7 % 1 ~ 2 % , Exams ale of Apelication . Reference "Wards Engine and Vehicle Technology Update," June 15, 2001, p. 7 5% FE Conclusions: Potential for electronic thermal management is 5% FE improvement l Electric Power Steering | FC Improvement From Base From Ref. Technology Using electric motor to drive power steering Description Primary Benefits Reduced parasitic losses due to optimized operation (only when needed) Second lary None Benefits | FC Improvement | Base: 2V baseline engine; Reference: 4V OHC engine | 3.5 ~ 7.5 % | 1.5 - 2.5 % Example of Application Reference | ZF Lenksysteme: D. Peter, R. Gerhard | | 2- 3% SAE-Paper 199-01-0401 Conclusion: Reduction of fuel consumption by 2-3% by using electrical power steering instead of hydraulic power steering for a medium-sized vehicle. .