6
Costs and Benefits of Integrating Fuel Consumption Reduction Technologies into Medium- and Heavy-Duty Vehicles

The costs and benefits of particular measures to reduce fuel consumption can be estimated with some degree of precision. Before manufacturers or users invest in a particular technology, they must have an idea of the likely payoff, in terms of cost, reliability, performance, and fuel consumption. In addition to the direct costs and benefits discussed here, there are a number of indirect costs, indirect benefits, and unintended consequences related to the implementation of energy-efficient technologies in commercial vehicles.

In this chapter the committee further discusses the fuel consumption technologies identified in Chapters 4 and 5 with regard to their performance in different vehicle classes, which will largely determine what technologies will be used in various vehicles. The committee also discusses the costs of these technologies and their cost-benefit ratio. Operating and maintenance (O&M) costs are discussed as well as indirect effects.

The committee evaluated a wide range of fuel-saving technologies for medium- and heavy-duty vehicles. Some technologies, such as certain aerodynamic features, automated manual transmissions, and wide-base single low-rolling-resistance tires, are already available in production. Some of the technologies are in varying stages of development, while others exist only in the form of simulation models. Reliable, peer-reviewed data on fuel-saving performance are available only for a few technologies in a few applications. As a result, the committee had to rely on information from a wide range of sources, (e.g., information gathered from vehicle manufacturers, component suppliers, research labs, and major fleets during site visits by the committee), including many results that have not been duplicated by other researchers or verified over a range of duty cycles.

There is a tendency among researchers to evaluate technologies under conditions that are best suited to that specific technology. This can be a serious issue in situations where performance is strongly dependent on duty cycle, as is the case for many of the technologies evaluated in this report. One result is that the reported performance of a specific technology may be better than what would be achieved by the overall vehicle fleet in actual operation. Another issue with technologies that are not fully developed is a tendency to underestimate the problems that could emerge as the technology matures to commercial application. These issues often result in implementation delays as well as a loss of performance compared to initial projections. As a result of these issues, some of the technologies evaluated in this report may be available later than expected, or at a lower level of performance than expected. Extensive additional research would be needed to quantify these issues, and regulators will need to allow for the fact that some technologies may not mature as expected.

The fuel-saving technologies that are already available on the market generally result in increased vehicle cost, and purchasers must weigh the additional cost against the fuel savings that will accrue. In most cases, market penetration is low at this time. Most fuel-saving technologies that are under development will also result in increased vehicle cost, and in some cases, the cost increases will be substantial. As a result, many technologies may struggle to achieve market acceptance, despite the sometimes substantial fuel savings, unless driven by regulation or by higher fuel prices. Power train technologies (for diesel engines, gasoline engines, transmissions, and hybrids) as well as vehicle technologies (for aerodynamics, rolling resistance, mass/weight reduction, idle reduction, and intelligent vehicles) are analyzed in Chapters 4 and 5. Figure 6-1 provides estimates for potential fuel consumption reductions for typical new vehicles in the 2015 to 2020 time frame, compared to a 2008 baseline.

The technologies were grouped into time periods based on the committee’s estimate of when the technologies would be proven and available. In practice, timing of introduction will vary by manufacturer, based in large part on individual company product development cycles. In order to manage product development costs, manufacturers must consider the overall product life cycle and the timing of new product introductions. As a result, widespread availability of some technologies may not occur in the time frames shown.

The percent fuel consumption reduction (% FCR) num-



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6 Costs and Benefits of Integrating Fuel Consumption Reduction Technologies into Medium- and Heavy-Duty Vehicles The costs and benefits of particular measures to reduce the overall vehicle fleet in actual operation. Another issue fuel consumption can be estimated with some degree of pre- with technologies that are not fully developed is a tendency cision. Before manufacturers or users invest in a particular to underestimate the problems that could emerge as the technology, they must have an idea of the likely payoff, in technology matures to commercial application. These issues terms of cost, reliability, performance, and fuel consumption. often result in implementation delays as well as a loss of In addition to the direct costs and benefits discussed here, performance compared to initial projections. As a result of there are a number of indirect costs, indirect benefits, and these issues, some of the technologies evaluated in this report unintended consequences related to the implementation of may be available later than expected, or at a lower level of energy-efficient technologies in commercial vehicles. performance than expected. Extensive additional research In this chapter the committee further discusses the fuel would be needed to quantify these issues, and regulators will consumption technologies identified in Chapters 4 and 5 need to allow for the fact that some technologies may not with regard to their performance in different vehicle classes, mature as expected. which will largely determine what technologies will be used The fuel-saving technologies that are already available in various vehicles. The committee also discusses the costs of on the market generally result in increased vehicle cost, and these technologies and their cost-benefit ratio. Operating and purchasers must weigh the additional cost against the fuel maintenance (O&M) costs are discussed as well as indirect savings that will accrue. In most cases, market penetration effects. is low at this time. Most fuel-saving technologies that are The committee evaluated a wide range of fuel-saving under development will also result in increased vehicle cost, technologies for medium- and heavy-duty vehicles. Some and in some cases, the cost increases will be substantial. As technologies, such as certain aerodynamic features, automat- a result, many technologies may struggle to achieve market ed manual transmissions, and wide-base single low-rolling- acceptance, despite the sometimes substantial fuel savings, resistance tires, are already available in production. Some of unless driven by regulation or by higher fuel prices. Power the technologies are in varying stages of development, while train technologies (for diesel engines, gasoline engines, others exist only in the form of simulation models. Reliable, transmissions, and hybrids) as well as vehicle technologies peer-reviewed data on fuel-saving performance are available (for aerodynamics, rolling resistance, mass/weight reduc- only for a few technologies in a few applications. As a result, tion, idle reduction, and intelligent vehicles) are analyzed in the committee had to rely on information from a wide range Chapters 4 and 5. Figure 6-1 provides estimates for potential of sources, (e.g., information gathered from vehicle manu- fuel consumption reductions for typical new vehicles in the facturers, component suppliers, research labs, and major 2015 to 2020 time frame, compared to a 2008 baseline. fleets during site visits by the committee), including many The technologies were grouped into time periods based results that have not been duplicated by other researchers or on the committee’s estimate of when the technologies would verified over a range of duty cycles. be proven and available. In practice, timing of introduction There is a tendency among researchers to evaluate tech- will vary by manufacturer, based in large part on individual nologies under conditions that are best suited to that specific company product development cycles. In order to manage technology. This can be a serious issue in situations where product development costs, manufacturers must consider performance is strongly dependent on duty cycle, as is the the overall product life cycle and the timing of new product case for many of the technologies evaluated in this report. introductions. As a result, widespread availability of some One result is that the reported performance of a specific technologies may not occur in the time frames shown. technology may be better than what would be achieved by The percent fuel consumption reduction (% FCR) num- 

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 TECHNOLOGIES AND APPROACHES TO REDUCING THE FUEL CONSUMPTION OF MEDIUM- AND HEAVY-DUTY VEHICLES FIGURE 6-1 Comparison of 2015-2020 new-vehicle potential fuel-saving technologies for seven vehicle types: tractor trailer (TT), Class 3-6 Figure S-1 Comparison of 2015-2020...and Class 2b pickups.eps box (box), Class 3-6 bucket (bucket), Class 8 refuse (refuse), transit bus (bus), motor coach (coach), and Class 2b pickups and vans (2b). NOTE: TIAX (2009) only evaluated the potential benefits ofbitmapdriver management and coaching for the tractor-trailer class of vehicles. It is clear to the committee that other vehicle classes would also benefit from driver management and coaching, but studies showing the benefits for specific vehicle classes are not available. For more information, see the subsection “Driver Training and Behavior” in Chapter 7. Also, potential fuel reductions are not additive. For each vehicle class, the fuel consumption benefit of the combined technology packages is cal - culated as follows: [% FCRpackage = 100 [1 – (1 – {% FCRtech1/100}) (1 – {% FCRtech2/100)} … (1 – {% FCRtechN/100})]. Values shown are for one set of input assumptions. Results will vary depending on these assumptions. SOURCE: TIAX (2009). Fuel Consumption Reductions bers shown for individual technologies and other options are not additive. For each vehicle class, the % FCR associated The fuel consumption reductions identified in Chapters with combined options is as follows: 4 and 5 can be summarized in a broad matrix of vehicle applications versus technology, for the years 2015 to 2020, % FCRpackage = 100 [1 – (1 – {% FCRtech1 /100}) as shown in Table 6-2 and Figure 6-1. The most effective (1 – {% FCRtech2/100}) … {(1 – {% FCRtechN /100})] where % FCRtechx is the percent benefit of an individual TABLE 6-1 Technologies and Vehicle Classes Likely to technology. See Benefits Tractor Urban Motor Class Class Refuse DIRECT COSTS AND BENEFITS Technologies Trailer Bus Coach 3-7 2b Truck Trailer aerodynamics X Technology Applications to Specific Vehicle Classes Cab aerodynamics X X X X The technologies discussed in Chapters 4 and 5 can be Tires and wheels X X X X X X Weight reduction X X X X X X consolidated into 12 categories and then a judgment made re- Transmission and X X X X X X garding the benefits by broad vehicle class. Table 6-1 shows driveline the applications in which these technologies will be effec- Accessory X X X X X tive. Some technologies are broad enough to be applied to electrification all classes: tires and wheels, weight reduction, transmission Overnight idle X reduction and driveline, engine efficiency, and hybridization. Others Idle reduction X X X X are more specific to the class of vehicle, such as replacing Engine efficiency X X X X X X gasoline engines with diesel engines (dieselization), which Waste heat recapture X X is applicable only to Class 2 to 7 vehicles, where gasoline Hybridization X X X X X X engines are offered today. Dieselization X X

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 COSTS AND BENEFITS OF INTEGRATING FUEL CONSUMPTION REDUCTION TECHNOLOGIES TABLE 6-2 Fuel Consumption Reduction (percentage) by Application and Vehicle Type Application Engine Aerodynamics Rolling Resistance Transmission and Driveline Hybrids Weight Tractor trailer 20 11.5 11 7 10 1.25 Straight truck box 14 6 3 4 30 4 Straight truck bucket 11.2 0 2.4 3.2 40 3.2 20a Pickup truck (gasoline) 3 2 7.5 18 1.75 23b Pickup truck (diesel) 3 2 7.5 18 1.75 Refuse truck 14 0 1.5 4 35 1 Transit bus 14 0 1.5 4 35 1.25 Motor coach 20 8 3 4.5 NA 1.05 aCompared to a baseline gasoline engine. bCompared to baseline diesel engine. SOURCE: Adapted from TIAX (2009). technologies in terms of fuel consumption reduction are as frame, but data are also presented for the 2013 to 2015 time follows: frame. The applications discussed are tractor trailer, straight truck, pickup truck and van, refuse truck, transit bus, and • Hybridization motor coach. After considering these vehicle applications, • Replacement of gasoline engines with diesel engines alternative metrics for cost-benefit ratio are presented. • Improvement in diesel engine thermal efficiency • Improvement in gasoline engine thermal efficiency Tractor Trailer • Aerodynamics, especially on tractor-trailer applica- tions T his category of vehicles includes Class 8 tractors • Reduced rolling resistance equipped with so-called fifth wheels for hitching to one • Weight reduction or more trailers. The baseline vehicle for fuel consump- tion estimates is an older-generation aerodynamic tractor (drag coefficient, Cd = 0.63 to 0.64) with a sloped hood, Costs, Cost-Benefit, and Implementation of These roof fairings, aero bumpers, standard dual tires (coefficient Technologies of rolling resistance, Crr = 0.0068), standard 53-ft box van The committee determined the direct costs of the tech- trailer, a diesel engine with peak thermal efficiency of 41 to nologies in several ways: 42 percent, and cycle thermal efficiency of 37 to 39 percent on a long-haul cycle with long periods of constant speed • Estimates of presenters and manufacturers for the retail operation, camshaft-driven unit injection at 2,000 bar, vari- price equivalent (RPE), for the components and/or able geometry turbocharger, cooled exhaust gas recirculation package. (EGR), a diesel particulate filter (DPF) for particulate matter • Dealer’s data book list prices multiplied by 0.6 to (PM) control, a cylinder pressure limit of 200 bar, and a 10- estimate RPE.1 speed manual transmission with overdrive. • Complete vehicle cost premiums from various publica- tions, such as for a hybrid bus. Engine (0 to 00). Improved thermal efficiency from 42 percent peak to 52.9 percent peak efficiency compared to In the following discussion and tables, the committee the 2008 baseline, which represents a 20 percent reduction presents fuel consumption, in percent reduction, as a range in fuel consumption. The baseline 2010 technology includes or as one number representing its best estimate.2 Similarly, a DPF at a cost of $7,000 and a selective catalytic reduction the capital costs are presented as a range or as one number (SCR) catalyst at a cost of $9,600. The 2015-2020 technol- representing the committee’s best estimate. The number for ogy includes SCR with improved nitrogen oxides (NOx) costs is then divided by the number for fuel consumption conversion efficiency, a U.S. Environmental Protection reduction (dollar cost/% fuel consumption reduction, $/%), Agency (EPA) required onboard diagnostic (OBD) system and the result is called capital cost per percent reduction with closed loop controls, a high-pressure common rail fuel (CCPPR). Most of the focus is on the 2015 to 2020 time system with higher injection pressure of about 3,000 bar, piezo-electronic fuel injectors, increased cylinder pressure capability to 250 bar, and a bottoming cycle. The incremental 1 Personal communication from Dave Merrion to the committee, May cost is in the range of $23,000 in addition to the cost of 2010 27, 2009. emissions aftertreatment hardware. Besides the increase in 2The cost data are primarily from TIAX (2009) unless noted otherwise.

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 TECHNOLOGIES AND APPROACHES TO REDUCING THE FUEL CONSUMPTION OF MEDIUM- AND HEAVY-DUTY VEHICLES up-front capital cost, O&M costs will increase due to the in - technology that is already available on the market is the creased complexity of the engine system. The combined total automated manual transmission (AMT). With an AMT cost must be taken into account in any analysis, and the cost the clutch is only used to launch the vehicle and then the may make the advanced technologies unattractive for many transmission shifts automatically. The AMT does not have applications, particularly low-mileage applications. the powershift capability of a fully automatic transmission and thus does not have the productivity improvement of an Aerodynamics. In the 2015-2020 time frame, the committee automatic. The power interruption during an AMT shift is projects that a tractor-trailer combination Cd of about 0.45 very similar to that of a manual transmission, but use of the should be feasible.3 This requires developments going be- controller to determine shift points tends to remove some yond the existing EPA SmartWay specification, which results of the driver effect on fuel consumption variability. In ad- in drag coefficients in the 0.50 to 0.55 range. To achieve this dition, low-viscosity synthetic lubricants can be used in the improvement, changes in vehicle operations and infrastruc- transmission (manual or AMT) and throughout the driveline. ture (such as loading docks) are likely to be necessary. Costs This combination of AMT and synthetic lubricants can re- are estimated for one tractor and three trailers, since this is duce fuel consumption by 2 to 8 percent and has a projected the typical ratio of tractors to trailers in the field. An improve- cost of $5,800. Fully automatic transmissions do not offer ment in Cd from 0.63 to 0.45 will result in a fuel savings of significant productivity (trip time) or fuel savings in long- 11.5 percent on a high-speed, long-haul duty cycle and 15 haul operations. Therefore, fully automatic technology is not percent at 65 mph. This savings is very dependent on the expected to gain significant share in the long-haul market. actual vehicle duty cycle. High average speeds will result in However, in urban and suburban driving, a switch to fully achieving the projected savings, while applications in more automatic transmissions can result in significant fuel savings congested areas with lower average speeds will achieve a (up to 5 percent) and significant productivity improvements smaller benefit. The cost of this package for the tractor is at a cost of about $15,000. Another driveline option that is feasible for 2015 and beyond is the 6 × 2 tractor layout. Most in the range of $2,700 to $3,500 (TIAX, 2009, Table 5-1). The trailer aerodynamics cost $3,000 per trailer. The overall tractors have two drive axles in a configuration referred to as 6 × 4 (six wheels, with four of them driven). A 6 × 2 tractor cost of aerodynamic features for a tractor and three trailers is estimated at $12,000. Aerodynamic features also bring with has only one drive axle, and the second rear axle only carries them O&M costs that need to be considered. The primary the weight of the truck. The use of a single drive axle saves cost is repair or replacement due to damage encountered in about 1 percent of fuel consumption, at the expense of lost operation. For example, many fleets today avoid the use of traction. This option may not be feasible for applications in fuel-tank skirts on tractors, because these can have a very areas with significant snow or for vehicles that must also short life in the field in some applications. Trailer skirts operate off highway. Truck purchasers may be worried about loss of resale value if they purchase 6 × 2 tractors, since the are also known to be damage prone. Future aerodynamic improvements may impose additional costs due to changes resale market places a premium on tractors that can be used in vehicle operation, infrastructure, or capability, and these in a wide variety of applications. costs must be taken into account. Hybrid Tractor Power Trains. The use of hybrid power Rolling Resistance. Widespread implementation of wide- trains in Class 8 tractor trailers has been assigned a low prior- base single tires with low rolling resistance is expected to ity in the long-haul market, by manufacturers, due to the typi- be feasible in 2015 to 2020 for both tractors and trailers. cal duty cycle of mainly constant speed long-haul operation, Using rolling resistance values projected by Michelin and which provides little opportunity for battery or hydraulics to the EPA, the NESCCAF/ICCT (2009, p. 51) report projects store and release energy. As it turns out, the highway tractor a benefit of 11 percent compared to standard dual tires. The trailer spends a significant amount of time on arterial high- cost of applying wide-base singles to one tractor and the ac- ways, on grades that provide regenerative braking opportuni- companying three trailers is projected by NESCCAF to be ties, and idling. NESCCAF/ICCT (2009, p. 54) showed fuel $4,480 (NESCCAF/ICCT, 2009, p. 95) and by TIAX (2009, consumption reduction of 5.5 to 6 percent on one sample p. 5-2) to be $3,600. long-haul duty cycle including some suburban segments and some grades. For those trucks that idle overnight to support Transmission and Drieline. The manual 10-speed transmis- the “hotel load” of the sleeper, NESCCAF/ICCT showed an sion, with overdrive, is considered the baseline transmission, additional benefit of about 4 percent, for a total benefit of along with a tandem rear axle with various ratios that can 10 percent. TIAX estimates the cost of the parallel hybrid be specified when the vehicle is purchased. An alternate modeled in the NESCCAF report at $25,000 in the 2015 to 2020 time frame, which assumes that significant volumes 3 Note that the estimates provided here apply only to standard 53-ft van will be reached by 2015. Note that there is little actual field trailers. Other trailer types will allow some degree of aerodynamic improve- data available on the application of hybrids to Class 8 tractor ment, but the baseline Cd, the degree of improvement available, and the cost trailers, so only simulation data were used to estimate fuel of the improvement will all vary substantially by trailer type.

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 COSTS AND BENEFITS OF INTEGRATING FUEL CONSUMPTION REDUCTION TECHNOLOGIES savings. O&M costs will also be a critical factor in hybrid in a slightly modified format, and includes the total potential applications. Insufficient data are available today to project benefit that can be achieved for Class 8 tractor trailers in the life of batteries, which will be a major cost borne in most the 2015 to 2020 time frame. Note that the total percentage cases by the second or third owner of the vehicle. In many benefit is not simply a sum of the individual benefits. As in- cases, later owners may elect not to repair a failed hybrid cremental improvements are added, each percentage benefit system (because of the high cost) as long as the vehicle is applies to an already reduced fuel consumption, not to the able to operate without using the hybrid system. baseline fuel consumption. As a result, the total benefit Poverall is calculated as follows: Idle Reduction. Several idle reduction technologies were 1 − Poerall = (1 − p1)(1 − p2)…(1 − pn). discussed in Chapter 5 and are summarized in Table 6-3. Note that the benefit of an idle timer is not additive with APU or other hotel load systems, since the benefits claimed Using this formula, the total overall benefit available is 50.5 by these systems already include idle elimination. The idle percent, whereas a simple summation of the benefits would timer cannot be effective if the engine is used to support ho- suggest a 65 percent overall benefit. tel loads, but it can reduce idling at loading docks and other times where the hotel load is not required. If a hybrid system Tractor-Trailer Summary is used, idle reduction comes at no extra cost. The CCPPR ratios of technologies, expressed in dollars All the technologies listed in Table 6-5 may be imple- per percent fuel consumption reduction, are summarized in mented in production in the 2015 to 2010 time frame, Table 6-4 for Class 8 tractor trailers in the 2015 to 2020 time taking into account the comments made in the following frame. Table 6-5 presents the same information as Table 6-4 subsections. TABLE 6-4 Technology for Class 8 Tractor Trailers in the TABLE 6-3 Idle-Reduction Packages 2015-2020 Time Frame Fuel Cost ($), Consumption Retail Price Mean Technology Savings (%) Equivalent Capital Improvement in Cost Fuel Consumption CCPPR Engine electronic control unit acts as an 2-3 0 Technology ($) (%) ($/%) idle timer (programmable) Direct-fired heater 1-3 1,000-3,000 23,000a Diesel engine 20 1,150 Small auxiliary power unit or battery 4-6.5 5,000-8,000 Aerodynamics (tractor trailer) 12,000 11.5 1,043 system Rolling resistance 3,600 11 327 Large auxiliary power unit 5-8 8,000-12,000 Transmission and driveline 5,800 4 1,450 Hybrid system used for idle elimination 4-6.5 (cost covered Hybrid (includes idle reduction) 25,000 10 2,500 by hybrid) Weight reduction 13,500 1.25 10,800 NOTE: CCPPR, capital cost per percent reduction. aNot including $9,000 selective catalytic reduction. TABLE 6-5 Tractor Trailers Benefit from Advances in Every Technology Category % Fuel Consumption Capital CCPPR Weight Category Description Benefit Cost ($) ($/%) (lb) Aerodynamics Improved SmartWay tractor + three aerodynamic trailers 11.5 12,000 1,043 750 Engine Advanced 11-15L diesel with bottoming cycle 20 23,000 1,150 800 Tire Improved WBS on tractor + three trailers 11 3,600 327 −400 Transmission and driveline AMT, reduced driveline friction 7 5,800 829 80 Hybrid Mild parallel hybrid with idle reduction 10 25,000 2,500 400 Management and coaching 60 mph speed limit; predictive cruise control with telematics; driver training 6 1,700 283 — Idle reduction Included with hybrid system — — — — Total added weight Added components −1 — — +2,030 Weight reduction Material substitution—2,500 lb. 1.25 13,500 10,800 −2,500 TOTAL 2015-2020 Package 50.5 84,600 1,674 −470 NOTE: For each vehicle class, the fuel consumption benefit of the combined technology packages is calculated as follows: [% FCR package = 100 [1 – (1 – {% FCRtech1/100 }) (1 – {% FCR tech2/100}) … (1 – {% FCRtechN/100})] where % FCRtech x is the percent benefit of an individual technology. CCPPR, capital cost per percent reduction. SOURCE: TIAX (2009), p. 5-2.

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 TECHNOLOGIES AND APPROACHES TO REDUCING THE FUEL CONSUMPTION OF MEDIUM- AND HEAVY-DUTY VEHICLES Diesel Engines. Diesel engines used in Class 8 tractors ogy are already available, including both onboard systems are expected to begin improving their thermal efficiency as (APUs, diesel-fired heaters, etc.) and remote systems such as emissions regulations stabilize after 2010. A peak thermal truck stop heating, ventilation, and air conditioning (HVAC) efficiency of 53 percent may be achievable in the 2015- systems. If hybrid systems are adopted for tractor-trailer 2020 time frame (a 20 percent improvement over current trucks, they will provide a built-in idle reduction capability. engines). Given the cost of some of the technologies required It is not clear which of the existing technologies will come to to achieve this improvement, it is likely that this level of dominate the idle reduction market or if some future technol- improvement will only be achieved with the use of incen- ogy will dominate. It is possible that no one idle reduction tives or regulation. Because of the high cost and difficult technology will become dominant. packaging of some advanced technologies, some of these technologies will probably be restricted to certain high- Straight Truck mileage applications. This category of vehicle is very broad, including Class 3 Aerodynamics. The current average drag coefficient is to 8 straight (i.e., nontrailer) trucks, so it includes cut-away about 0.63, and the best currently available is 0.50 to 0.55 vans, parcel delivery vehicles, beverage delivery vehicles, (SmartWay-certified tractors and trailers). In the 2015 to shuttle buses, cab over engine cabs, conventional cabs, both 2020 time frame, drag coefficients around 0.45 should be gasoline and diesel engines, and various forms of work feasible. Some of these changes may require changes in the trucks described in Chapters 1 and 3. The baseline vehicle, way vehicles operate, including infrastructure changes, such for fuel consumption estimates, is a pickup and delivery as loading dock height change. Changing a fundamental Class 6 regional haul, traveling about 150 miles per day at an parameter such as loading dock height would require a huge average speed of 30 mph. The 2007 certification, 6-9L diesel investment that will not occur without regulatory stimulus. engine, has a cycle thermal efficiency of 31 to 35 percent and The cost and fragility of drag reduction features need to be a peak thermal efficiency of 40 to 41 percent (TIAX, 2009, dealt with in order to make them more attractive from a cost- Table 4-5). The engine has high-pressure common rail fuel benefit standpoint. Aerodynamic improvements for other injection (1,800 bar), is equipped with a turbocharger, cooled trailer configurations (bulk hauler, flatbed, tanker, etc.) are EGR, a DPF, and about 175 bar cylinder pressure. The ve- not well understood and require further research. hicle has no aerodynamic treatment and standard tires with steel wheels. The transmission is a six-speed automatic with Rolling Resistance. Widespread implementation of wide- no anti-idle technologies. base single tires should be possible in the 2015 to 2020 time frame. These tires have an attractive CCPPR ratio and Engine. The diesel engine is considered baseline in this ap- thus may achieve broad application without incentives or plication, but the gasoline engine penetration was 42 percent regulation. in 2008 and has been increasing in the past few years. The in- crease in gasoline engine penetration is due to the recent cost Transmission and Drieline. For tractor-trailer combination increase of diesel engines, especially from addition of the vehicles, automated manual transmissions combined with DPF in 2007. Furthermore, the prospect of SCR or advanced low-friction driveline components and lubricants should be EGR in 2010 is expected to serve as an additional sales deter- widely implemented in the 2015 to 2020 time frame. Other rent for those classes whose duty cycles are more urban and transmission concepts may become feasible in that time have relatively low annual vehicle miles traveled (VMT). frame, but the technology is not far enough along to make Dieselization of this class provides a large fuel consump- any reliable forecasts. The widespread implementation of tion reduction (about 30 percent), but the incremental cost the 6 × 2 tractor configuration is very uncertain, given con- of the diesel engine beyond 2015 will be high due to further cerns about limited usefulness of the vehicle to subsequent emissions compliance modifications and implementation of owners. EPA-required OBD systems with closed loop controls. Also problematic to diesel sales is that the diesel fuel Hybrid Tractor Power Trains. Hybrid power trains for consumption cost benefit was nearly wiped out in mid-2008 tractor-trailer vehicles are technically feasible for the 2015 to when the diesel fuel price per gallon increment was about 2020 time frame. The question will be whether the high cost $0.80 (20 percent) above gasoline (itself at $4.00). While in October 2009 this differential was only 5 percent,4 it may and added weight are justified by the potential fuel savings of around 6 percent for tractors that do not include sleeper shrink when product demand rises with an improving econ- operation and 10 percent for sleepers. Widespread applica- omy. In addition to the 2010 emissions, the advancing diesel tion of hybrids in tractor-trailer applications is very unlikely technology beyond 2015 will likely include 42 percent cycle without substantial incentives or regulation. 4 See http://tonto.eia.doe.gov/oog/info/gdu/gasdiesel.asp; accessed Oc- Idle Reduction. Several forms of idle reduction technol- tober 6, 2009.

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 COSTS AND BENEFITS OF INTEGRATING FUEL CONSUMPTION REDUCTION TECHNOLOGIES thermal efficiency and 45 percent peak thermal efficiency, duty cycle described. The package cost is more than $3,000, facilitated by increased injection pressure (2,000 to 2,400 which provides an extremely poor value for a truck averaging bar), improved SCR conversion efficiency, and some engines 30 mph. equipped with multistage turbochargers and accompanying increased cylinder pressure (about 200 bar), plus reduced Rolling Resistance. Currently available low-rolling- parasitic losses. These improvements result in a 13 to 16 per- resistance SmartWay dual tires can give a fuel consumption cent reduction in fuel consumption, but principally only for reduction of 1 to 2 percent at a cost of $120 per rear axle. The those applications where heavier loaded duty cycles are the reduced Crr duals provide a simple payback in 4 months for norm. The cost premium is $11,000 to $14,000, largely for the assumed baseline truck. Current wide base single (WBS) SCR or advanced EGR and OBD (TIAX, 2009, Table 3-8). tires can give a fuel consumption reduction of 2 to 4 percent Selection of a diesel or gasoline engine from the develop- at a cost of $450 per rear axle (TIAX, 2009). The WBS tires ing engine technologies will consider cost benefits associated require about 8 months for payback, but early evaluations with widely varying duty cycle and durability needs. have shown poor tread wear in tighter turning conditions Diesel engine technology continues to be strongly devel- of urban operation. Yet the WBS tires could be used in this oped mainly for Class 8 tractor-trailer duty, and the smaller sector where the duty cycle is mainly arterial and interstate. Class 3 through 7 diesel engines benefit from this develop- As SmartWay has helped provide the greatest incentive for ment. Gasoline engine technology is also developing (as low-Crr tires, nearly all of that program has been tractor discussed in Chapter 4 and the Class 2b pickup section of trailer focused, and the Class 3 to 7 sector has not had much Chapter 5) and may capture an increasing proportion of attention toward this feature. medium-duty trucks in the sector (i.e., Classes 3 to 7 and I t is expected that the next-generation low-rolling- perhaps even some of the lighter duty vehicles of Class 8). resistance duals in circa 2013 will reduce fuel consumption These are straight trucks with relatively low VMT or with from the 2007 base by 2.8 to 3.5 percent, also at a cost of both lighter average loads and lower average speeds. Bucket $120 per axle (TIAX, 2009, Table 3-8). Applications are trucks and most service trucks are among the best examples. likely that cannot use low-rolling-resistance tires because Diesel engines in this sector will best serve those operations of traction issues. Examples include dump trucks, cement that require higher loads, higher annual VMTs, higher aver- mixers, and service trucks that must occasionally operate off age speed applications, and longer durability. road. Aerodynamics. The aerodynamic packages for medium- Transmission and Drieline. The six-speed fully automatic duty trucks are not part of the OEM/dealer standard options transmission (AT) is considered baseline in this sector, like they are on tractor trailers. Aerodynamic features (roof especially for pickup and delivery operation in urban and deflectors, fuel tank fairings, box skirts, mirrors, etc.) are suburban areas. In those cases fuel consumption favors the available (four of the six identified features) as options and AT, as does improved productivity (in terms of trip speed; are dealer installed (except cab streamlining). Table 6-6 Allison Transmission). Further, the AT is used by many op- identifies the aero opportunities for this style of truck. erators for safety reasons (two hands on the wheel) and for A 1.5 percent fuel savings reflects the base truck’s 30 mph reduced driver training needs. Manual transmissions and, average duty-cycle speed. Larger benefits can be achieved increasingly, automated manual transmissions (AMTs) will for those trucks that operate at higher average speeds, but be favored for higher annual VMTs in arterial and interstate these higher speeds are not typical of a pickup and delivery routes, as they will result in fuel consumption improvements. TABLE 6-6 Straight Box Truck Aerodynamic Technologies FC Benefita (%) Technology CD Improvement (%) Capital Cost ($) Status Aerodynamic Devices Roof deflector 2-3 7-7.5 500-800 Available Chassis fairings 0.5-1 2.5-3 400-500 Not available Box skirts 2-3 4.5-5 500-1,000 Demos Box fairing 0.5-1 2.4-2.7 500-650 Available Cab streamlining 1-2 5-6 750 Available Aft box taper 1.5-3 7.6-8 1,000 Not available Aerodynamic Packages 5-8b Combination of straight truck aerodynamics 20 3,000-3,500 Not available aFuel consumption (FC) benefit is critically dependent on duty-cycle average speed. bAbout 1.5 percent for the baseline average speed of 30 mph. SOURCE: TIAX (2009), Table 3-8.

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 TECHNOLOGIES AND APPROACHES TO REDUCING THE FUEL CONSUMPTION OF MEDIUM- AND HEAVY-DUTY VEHICLES For these conditions a reduction of 4 percent may be achieved system, and is likely to lead utilities to consider converting (TIAX, 2009, p. 4-70). These sorts of evolutions will occur to gasoline to reduce cost. slowly as particular operations experiment with different transmission solutions for small fuel consumption reductions Summary: Box and Bucket Class 6 Straight Trucks or productivity improvements. Altogether, it is not likely a major shift will occur. Diesel engines may continue to dominate this sector, especially for the medium- and heavy-duty applications Hybrid Power Trains. This vehicle sector has received the with higher annual vehicle miles traveled. Gasoline engines most attention for hybridization, after passenger cars and should capture increasing market share because of both urban buses. Electric systems are in early production, and technology improvements and the increasing diesel price both advanced electric and hydraulic systems are in develop- differential due to emission control systems. Hybrid solu- ment and/or demonstration. The fuel consumption reduction tions may further incentivize gasoline engines, since with a for an Eaton electric system in a Navistar or Kenworth truck hybrid the total power demand on the engine shrinks by 25 currently is 20 to 30 percent with a cost in 2014 of $20,000. to 40 percent. The cost will be driven by incorporation of higher volume Li- Hybridization in this sector will be the strongest contribu- ion batteries. This cost is nearly half that of the low-volume tor to reduced fuel consumption due to both percentage of (batches of hundreds at a time) units offered in fall 2009, power supplied by the hybrid and the expected cost benefit which use nickel metal-hydride batteries. The same system in the period beyond 2015 with the takeover by Li-ion bat- with an electric power takeoff, appropriate for a bucket truck, tery solutions as forecast by most observers (Research and will reduce fuel consumption by 30 to 40 percent with a 2014 Markets, 2009). Simple payback for the baseline straight cost of $30,000. box truck in this section is about three years. However, the Many companies, original equipment manufacturers substantially low VMTs of the bucket truck application put and suppliers, are focused on this segment for electric and simple payback at eight years, even considering that idle fuel hydraulic hybrids. Some companies are in production, such consumption (20 percent of the total) will be replaced by the as Freightliner M2 Business Class, Navistar Durastar, ISE, battery (TIAX, 2009, p. 2-5). These estimates are with $3.00 Azure, Kenworth, Peterbilt, and Workhorse Custom Chas- per gallon fuel. sis. A Duke University study5 estimates that 4,850 hybrids Both hybrid system and engine efficiency developments will be produced by 2010; 29,000 by 2015; and 60,000 by have been government incentivized as these have the highest 2020. This early penetration will be helped by EPA grants6 development costs and incur the greatest price increases and of $50 million for deploying hybrids, which provide federal with lack of success would impose the greatest loss of fuel tax credits for incremental costs as follows: 20 percent tax consumption reduction opportunity for this sector. The EPA credit for 30 to 40 percent fuel reduction, 30 percent tax hybrid grant program described previously is an example credit for 40 to 50 percent fuel reduction, and 40 percent tax of such an incentive. Nevertheless, the industry today is re- credit for more than 50 percent fuel reduction. (Note that markably immature, and low-volume high incremental price these credits have caps of $7,500, $15,000 and $30,000 for hybrid offerings could use some incentives to “get ready” for vehicles weighing 8,501 to 14,000 lb, 14,001 to 26,000 lb, the 2015 marketplace. and more than 26,000 lb, respectively.) Pickup Truck and Van (Class 2b) Cost-Benefit. The CCPPR of technology expressed in dol- lars per percent fuel consumption reduction is summarized Class 2b includes vehicles of 8,500 lb to 10,000 lb gross in Table 6-7 for Class 6 straight trucks in the 2015 to 2020 vehicle weight (GVW). For EPA and California Air Re- time frame. A 1 percent fuel savings equals about $225 per sources Board emission certification purposes, the classes year (at $3.00 per gallon fuel price). are as follows: Class 3 to 6 bucket trucks are also prevalent in this sector, • 8,500 to 19,500 lb light to heavy duty EPA8 and by virtue of the hybrid electrical system will substan- tially benefit from electrification of the vehicle’s power take- • 8,500 to 10,000 lb California MDV4 off (PTO) unit (see Table 6-8). One troublesome factor for • 10,000 to 14,000 lb California MDV5 bucket trucks in this sector is their average annual mileage of 13,300 miles as found by one study of 31 utilities.7 Such The baseline vehicle is a pickup truck or van with a 6- to mileage will greatly limit the potential payback of a hybrid 8-liter gasoline engine, naturally aspirated, port fuel injected, and a four-speed automatic transmission. 5 See Lowe et al. (2009). 6 See 8Vehicles http://www.epa.gov/otaq/diesel/projects.htm. up to 10,000 lb GVW used for personal transportation are 7T. Reinhart, personal communication to committee members, October 9, classified as medium-duty passenger vehicles and are subject to light-duty 2009, and phone interview with S. Bibono of Chatham Consulting, October vehicle legislation. Also complete heavy-duty diesel vehicles under 14,000 2009. Chatham does benchmarking surveys for the utility industry. lb can be chassis emission certified rather than engine-dyno certified.

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 COSTS AND BENEFITS OF INTEGRATING FUEL CONSUMPTION REDUCTION TECHNOLOGIES TABLE 6-7 Class 3 to Class 6 Straight Box Truck with 2015-2020 Technology Package Fuel Consumption Capital Benefit Cost CCPPR Weight Category Description (%) ($) ($/%) (lb) Aerodynamics Aero cab, skirts, round corners 6 3,250 542 300 Engine Advanced 6-9L Engine 14 13,000 929 400 Tire Improved low rolling resistance duals 3 300 100 — Transmission and driveline 8-speed automatic transmission, reduced driveline friction, aggressive shift logic 4 1,800 450 — Hybrid Parallel hybrid 30 20,000 667 400 Management and coaching — — — — — Idle reduction — — — — — Total added weight Added components −4.4 — — +1,100 Weight reduction Material substitution—1,000 lb 4 4,770 1,193 −1,000 Total 2015-2020 package 47.1 43,120 915 +100 NOTE: For each vehicle class, the fuel consumption benefit of the combined technology packages is calculated as follows: [% FCR package = 100 [1 – (1 – {% FCRtech1/100 }) (1 – {% FCR tech2/100}) … {(1 – {% FCRtechN/100})] where % FCRtech x is the percent benefit of an individual technology. CCPPR, capital cost per percent reduction. SOURCE: TIAX (2009). Fuel consumption can be reduced through vehicle modi- fuel consumption will be highly dependent on the application fications and systematic incorporation of advanced technolo- of the vehicle. If this class of vehicle is used primarily by gies into the power train. Engine fuel consumption can be contractors or local delivery services, the benefit of adding reduced by either applying advanced technologies to the aerodynamic treatments would be minimal. The report by spark ignition engine or substituting a diesel engine for the TIAX estimates a potential fuel consumption reduction of 3 spark ignition engine. Typical applications for a Class 2b percent with an incremental cost of $100 from aerodynamic vehicle would be as an urban delivery vehicle or a work ve- treatments (TIAX, 2009). hicle for a small contractor. For this application the average speed would not be high and there would be frequent stops. Rolling Resistance. Like aerodynamic improvement, the As such, the highest potential for reducing fuel consumption potential for fuel consumption reduction through low rolling will reside with engine improvements, hybridization, and resistance tires will be heavily dependent on the application. transmission improvement. Average vehicle miles traveled Again, assuming that the likely use for these vehicles will are also typically fairly low, which limits the payback of be local contractor-type work or urban delivery, the benefit fuel-saving technologies. from low rolling resistance tires will most likely be small: 2 percent at an incremental cost of approximately $10 (TIAX, Aerodynamics. The extent to which aerodynamic treatment 2009). of the vehicle will be a cost-effective approach to reducing TABLE 6-8 Class 3 to 6 Bucket Truck with 2015-2020 Technology Package Category Description % Benefit Capital Cost ($) CCPPR ($/%) Weight (lb) Aerodynamics — — — — — Engine Adv. 6-9 L engine 11.2 13,000 1,161 400 Tires Improved low-rolling-resistance duals 2.4 300 125 — Transmission and driveline Reduced driveline friction 3.2 1,800 450 — Hybrid Parallel hybrid with electric power takeoff 40.0 30,000 667 650 Management and coaching — — — — — Idle reduction — — — — — Total added weight Added components 3.4 — — 1,050 Weight reduction Materials substitution—1000 lb 3.2 4,770 1,193 –1,000 Total 2015-2020 package 49.6 49,870 1,005 50 NOTE: For each vehicle class, the fuel consumption benefit of the combined technology packages is calculated as follows: [% FCR package = 100 [1 – (1 – {% FCRtech1/100 }) (1 – {% FCR tech2/100}) … {(1 – {% FCRtechN/100})] where % FCRtech x is the percent benefit of an individual technology. CCPPR, capital cost per percent reduction. SOURCE: TIAX (2009), p. 5-3.

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0 TECHNOLOGIES AND APPROACHES TO REDUCING THE FUEL CONSUMPTION OF MEDIUM- AND HEAVY-DUTY VEHICLES Transmission. Incorporating a six- or eight-speed automatic Diesel Engine. If a diesel engine were used instead of a transmission with reduced driveline friction that incorporates spark ignition engine, fuel consumption could be reduced a shift logic aimed at minimizing fuel consumption could about 19 to 24 percent over the base engine at a cost of ap- potentially reduce fuel consumption by approximately 7 proximately $8,000 to $9,000. percent with an incremental cost on the order of $1,000 As one of the tasks in the committee’s contract with TIAX, (TIAX, 2009). a projection of fuel consumption reduction achievable for Class 2b pickups and vans was done for a selected technology Power Train. Hybridizing the vehicle power train would package. For this package aerodynamic improvements were have high potential for reducing fuel consumption for the assumed. Low rolling resistance tires, an eight-speed trans- application assumed to be typical for this vehicle class. The mission coupled to a parallel hybrid system, and minor light load-leveling, accessory electrification and electric launch weighting were also included. The package also included capability of the hybrid power train could reduce fuel con- an advanced turbocharged downsized stoichiometric direct- sumption on the order of 18 percent for this application. The injected gasoline engine. The improvements were projected incremental cost would be approximately $9,000 (TIAX, relative to the current baseline engine described above. This 2009). package results in projected fuel savings of 44.5 percent at a cost of $14,710, with no increase in vehicle weight. The time Engine. Starting from a base engine that is gasoline fu- frame in which it is likely that these technologies would be eled, spark ignited, naturally aspirated, and port fuel in- incorporated in a vehicle at significant market penetration is jected, many technologies could be introduced to reduce 2015 to 2020. A breakdown of the impact and incremental fuel consumption. Variable valve actuation (variable valve cost of the technologies in the package is shown in Table 6-9. timing—VVT, or variable valve lift—VVL) could reduce The committee also concluded that similar fuel consumption fuel consumption by 1 to 3 percent at incremental costs of benefits can be achieved with an advanced diesel engine in $120 to $750. Cylinder deactivation could reduce fuel con- place of a baseline gasoline engine. sumption by 2 to 3 percent at an incremental cost of around $75.9 Implementing direct injection while still operating Refuse Truck (Refuse Packer) at stoichiometric could reduce fuel consumption by 2 to 3 percent at an incremental cost in the range of $550 to $950. This vehicle class is distinguished by its unique duty Turbocharging and downsizing the direct-injected stoichio- cycle, its weight (Class 8 vehicle), and its excellent poten- metric engine could reduce fuel consumption an additional tial for hybridization. The packer cab design is often a low 2 percent at an incremental cost of approximately $1,200. cab-over-engine (LCOE) to aid ingress and egress by the Further improvements could be made by invoking lean burn operators. Its diesel engine is typically 9 to 11 liters in size operation to the stoichiometric direct injection turbocharged with 280 to 325 horsepower and drives through an automatic engine. A reduction in fuel consumption of 10 to 14 percent transmission. might be achieved by doing this. The incremental cost of lean For comparison of fuel consumption estimates, the base- burn over the direct-injected turbocharged stoichiometric en- line truck has an urban duty cycle of about 700 load stops gine is approximately $750. This incremental cost is the es- over 25 pickup miles a day, plus two round trips to a landfill timate for the exhaust aftertreatment system required for the for 50 additional miles. The truck has no aerodynamic de- lean burn engine. Finally, if homogeneous charge compres- vices and has a standard tandem axle with dual tires on steel sion ignition (HCCI)-like combustion can be implemented, wheels and a six-speed automatic transmission. The engine a reduction in fuel consumption of 10 to 12 percent could be is a diesel of 11 liters displacement with peak thermal ef- achieved relative to a stoichiometric direct injection engine. ficiency of 41 to 42 percent and cycle thermal efficiencies The incremental cost for HCCI would be around $685. of 34 to 37 percent, cam actuated electronic unit injection It is important to realize that there can be redundancy (2,300 bar), variable-geometry turbocharger, and cooled as well as synergy in applying these technologies. To get a EGR, plus DPF and 200-bar cylinder pressure. The packer more reliable estimate of the reduction in fuel consumption PTO hydraulic pump is engine driven. expected, the application of these technologies as packages in a simulation applied to the application of the engine in Engine. The current engine is forecast to be substantially question should be evaluated. evolved to an improved thermal efficiency of 49 percent (peak) which will provide a 14 percent reduction in fuel consumption, from a 2008 baseline. The 2020 technology includes optimized SCR with improved NO x conversion 9VVT, VVL, and cylinder deactivation fall into the class where their efficiency, OBD with closed loop controls, higher injection cumulative effect would not be additive. Variable valve actuation and cyl- inder deactivation applications will achieve some, or all, of their benefit by pressure, increased cylinder pressure, and turbocompound- reducing pumping losses. Consequently if all of these technologies were ing. The incremental cost is in the range of $14,000 to used on the same engine, the reduction in fuel consumption would not be $16,000, which is a 2010 engine with SCR plus $3,000 to the sum of the individual estimates given in this paragraph.

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 COSTS AND BENEFITS OF INTEGRATING FUEL CONSUMPTION REDUCTION TECHNOLOGIES TABLE 6-9 Class 2b Pickups and Vans with 2015-2020 Technology Package Category Description Benefit (%) Capital Cost ($) CCPPR ($/%) Weight (lb) Aerodynamics — 3 100 33 — Engine 5-8 L turbocharged downsized s-GDI 23 4,000 174 — gasoline engine Tire Improved low rolling resistance 2 10 5 — Transmission and driveline 8-speed automatic transmission, reduced 7.50 1,000 133 — driveline friction, aggressive shift logic Hybrid Parallel hybrid 18 9,000 500 300 Management and coaching — — — — — Idle reduction — — — — — Total added weight Added components –0.75 — — +300 Weight reduction 3%—~300 lb 0.75 600 800 –300 Total 2015-2020 package 44.5 14,710 331 0 NOTE: For each vehicle class, the fuel consumption benefit of the combined technology packages is calculated as follows: [% FCR package = 100 [1 – (1 – {% FCRtech1 /100 }) (1 – {% FCR tech2/100}) … {(1 – {% FCRtechN/100})] where % FCRtech x is the percent benefit of an individual technology. CCPPR, capital cost per percent reduction. SOURCE: TIAX (2009). $4,000 (TIAX, 2009). The automatic transmission will then Class 6 and 7 Navistar Durastar, Kenworth T270/T370, and use eight gears. Perterbilt 300 Series, which claim a 20 to 30 percent fuel consumption advantage at a cost of $38,000 to $40,000.10 Rolling Resistance. The use of low rolling resistance tires The Mack system is integrated in Mack’s own Class 8 LCOE has some application in refuse packers, but their low vehicle Terra-Pro refuse chassis and is equipped with a Mack 11-liter speed profile and the need for good traction makes the ap- engine certified for EPA 2010 with an SCR NOx aftertreat- plication questionable. ment system. Interestingly, Mack has captured about 50 percent of the LCOE Class 8 refuse sales for decades. Hybridization. Several hybrid concepts are being applied to refuse packers, including starter alternator motor, electric Idle Reduction. Idle timers and stop-start systems are ideal hybrid, and hydraulic hybrid. Demonstration systems are as for refuse packer cycles except when the engine power take- follows: off is needed. The engine pump for packing demands high horsepower during the packing cycle, and the recovered • Crane Carrier Company (electric and hydraulic) for braking energy stored by the hybrid system is reserved for the City of New York Department of Sanitation (CNY- vehicle launch assist. DOS; expected 30 to 50 percent reduction in fuel use; Calstart, 2008), Summary. Table 6-10 captures a likely solution package • Mack Trucks Inc. 120-kW integrated starter alternator for the refuse packer that is expected to be offered beyond motor, parallel hybrid electric operating with a 600-V 2015. Li-ion battery pack (expected 30 percent fuel con- sumption reduction), also for the CNY-DOS (Walsh, Refuse Truck Summary 2009, p. 1), • Crane Carrier and Bosch Rexroth Corp. (parallel hy- The above technologies for diesel engines and hybrids draulic hybrid) and Crane Carrier and ISE Corporation will be production implemented by 2020. Refuse truck fuel (series electric hybrid; Calstart, 2008). consumption reduction will most substantially result from improvements and innovations in the power train system, It is too early to know which of the several hybrid variants which then becomes increasingly complex. Other technolo- offer the best combination of cost and performance in the gies will be applied as spinoffs from Class 8 tractor-trailer refuse packer. But a hydraulic hybrid may perform well in applications (e.g., reduced transmission and driveline fric- such applications where hundreds of launch/stop cycles char- tion, accessory electrification, weight reduction, lower roll - acterize the longest portion of the operation day. It is noted ing resistance tires). that high-density residential packers using an automated side This sector is one of relatively low annual mileage (about loader arm will achieve up to 1,200 launch/stops in a 10-hour 20,000 miles), but the current average fuel consumption is day. This orientation for a hydraulic hybrid is a consequence quite high (33 to 40 gallons/100 miles), owing to the intensity of both energy recovery efficiency during heavy braking and incremental cost. 10 N . Naser, “Oshkosh Truck Corporation–AHHPS,” presentation to the The Eaton parallel electric system is being applied to the committee, Washington, D.C., February 8, 2007, slide 16.

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 TECHNOLOGIES AND APPROACHES TO REDUCING THE FUEL CONSUMPTION OF MEDIUM- AND HEAVY-DUTY VEHICLES a direct comparison of the costs of various fuel-saving tech- the cost is an extremely high $48.05 per gallon saved nologies in terms of how many dollars it costs to reduce a per year. vehicle’s fuel consumption by one gallon per year. Since the • The fuel consumption reduction potential for the mo- overall goal of energy policy is to reduce fuel consumption tor coach application, in the 2015 to 2020 time frame, at the least cost to society, the committee believes that the is 32 percent at a cost of $36,350, which results in a metric of dollars invested per gallon of fuel saved is a very cost benefit of $1,117 per percent fuel consumption good metric to consider. reduction. With a VMT of 56,000 miles per year and To calculate the proposed metric, information is need an average fuel consumption of 17.5 gallons per 100 on the average VMT and fuel consumption of the target miles (American Bus Association, 2006), the cost is vehicle class. Given this, it is easy to determine the number $11.59 per gallon saved per year. of gallons consumed per year by vehicles in the target class, and from there to determine the cost to reduce that fuel con- Table 6-20 summarizes a comparison of CCPPR mea- sumption in units of dollars per gallon saved per year. Some sured by dollars per percent fuel saved, compared to a metric examples: of dollars per gallon saved per year. A breakeven fuel price is also provided in the table. This breakeven price is the price • The fuel consumption reduction potential for the of fuel such that the value of the discounted fuel savings over tractor-trailer application, in the 2015 to 2020 time 10 years is just equal to the cost of the technology. This price frame, is 51 percent at a cost of $84,600. Assuming an does not necessarily reflect how truck buyers would evaluate average VMT of 120,000 miles per year and an average technologies, since they often do not plan to own the truck fuel consumption of 18 gallons/100 miles (data from for a full life, have a different discount rate, and would need VIUS, 2002), this results in a cost of $7.68 per gallon to consider O&M costs. However, a lifetime breakeven price saved per year. can be a useful metric for considering the social costs and • The fuel consumption reduction potential for Class benefits of regulation. Note that while the cost-effectiveness 6 box and bucket trucks, in the 2015 to 2020 time in terms of dollars per percent fuel saved is best for Class frame, is 47.1 percent for box trucks and 49.6 percent 2b, when measured in terms of dollars per gallon saved or for bucket trucks. The resulting cost for box trucks is breakeven fuel price, the Class 2b technologies prove to be $43,120 and the cost for bucket trucks is $49,870. For very expensive. Tractor-trailer trucks, which require a rela- Class 6 box trucks with an average VMT of 25,000 tively large investment per percent fuel saved, are actually miles per year and an average fuel consumption of the best bargain in terms of cost per gallon of fuel saved. The 12.5 gallons per 100 miles (committee estimates based on VIUS data), the cost is $29.29 per gallon saved per year. In the case of bucket trucks, where average VMT is 13,300 miles per year (survey result reported by TABLE 6-20 Fuel Consumption Reduction Potential Chatham Consulting) and average fuel consumption is for Typical Vehicles, 2015-2020, and Cost-Effectiveness 20 gallons per 100 miles (committee estimate, includ- Comparisons for Seven Vehicle Configurations ing fuel spent idling to support bucket operation), the Cost-Effectiveness Metric cost is $37.80 per gallon saved per year. • The fuel consumption reduction potential for the Class Dollars Dollars Fuel per per Breakeven 2b pickup and van application, in the 2015 to 2020 time Consumption Capital Percent Gallon Fuel frame, is 44.5 percent at a cost of $14,710. With an Pricea Reduction Cost Fuel Saved average VMT of 14,000 miles per year and an average Vehicle Class (%) ($) Saved per Year ($/gal) fuel consumption of 7 gallons per 100 miles (commit- Tractor-trailer 51 84,600 1,674 7.68 1.09 tee estimates), the cost is $33.73 per gallon saved per Class 6 box 47 43,120 915 29.30 4.17 year. truck • The fuel consumption reduction potential for refuse Class 6 bucket 50 49,870 1,006 37.80 5.38 truck trucks, in the 2015 to 2020 time frame, is 38.4 percent Class 2b pickup 45 14,710 331 33.73 4.81 at a cost of $50,800. At an average VMT of 20,000 Refuse truck 38 50,800 1,323 18.90 2.69 miles per year and an average fuel consumption of 35 Transit bus 48 250,400 5,232 48.05 6.84 gallons per 100 miles (committee estimates), the cost Motor coach 32 36,350 1,135 11.59 1.65 is $18.90 per gallon saved per year. NOTE: Values shown are for one set of input assumptions. Results will vary • The fuel consumption reduction potential for transit depending on these assumptions. bus applications, in the 2015 to 2020 time frame, is aCalculated assuming a 7 percent discount rate and a 10-year life, ex - 47.8 percent at a cost of $250,400. With an average cluding incremental operating and maintenance costs associated with the technologies. VMT of 35,167 miles per year and an average fuel SOURCE: Adapted from TIAX (2009). consumption of 31 gallons per 100 miles (TRB, 2009),

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 COSTS AND BENEFITS OF INTEGRATING FUEL CONSUMPTION REDUCTION TECHNOLOGIES TABLE 6-22 Incremental Operations and Maintenance transit bus stands out as a very expensive approach (without subsidies) to fuel saving by both metrics. Note that both of Costs these metrics include only initial purchase cost. Increases in Technology Cost per Mile ($) O&M costs are not included. Aerodynamics No increase Single wide tires and advanced lubricants 0.0040 OPERATING AND MAINTENANCE COSTS Hybrid power train 0.0060 Turbocompounding 0.0003-0.0007 Driver pay has historically been the highest expense for Bottoming cycle 0.0030 all sectors of the trucking industry. However, due to recent increases in energy costs, diesel fuel cost per mile (CPM) equals or exceeds driver pay as the top cost for many mo- namic devices, hybrid power train components, and waste tor carriers. Costs per mile are generally divided into two heat recovery systems (bottoming cycles) will increase com- groups, vehicle and driver based. Significant operational plexity and potentially maintenance costs. Use of OBD, as is costs include: required on exhaust emission devices, should allow informa- tion to be made available to reduce repair and maintenance • Vehicle-Based costs. Fuel and engine oil According to the NESCCAF/ICCT (2009)report, O&M Truck/trailer lease or purchase payments costs account for 5 percent of the total capital cost every Repair and maintenance 100,000 miles. An assessment was also made of incremental Fuel taxes O&M costs for new technologies (Table 6-22). Truck insurance premiums The estimated O&M costs provided in Table 6-22 are Tires projections, because many of the technologies are not in the Licensing and permits field yet. Field experience may result in significant changes Tolls to these projections. For example, the committee has heard • Driver-Based anecdotal evidence of substantial costs related to the repair Driver wages and maintenance of aerodynamic devices that are damaged Driver benefits in service. The committee did not have the resources to un- Driver bonuses dertake a complete study of operating and maintenance costs for all applications of future technologies. Additional study The results of the American Transportation Research In- is required to refine estimates of O&M costs for fuel-saving stitute (2008) survey of operating costs in terms of CPM and technologies, since in some cases O&M costs can represent cost per operating hour (CPH) are shown in Table 6-21. a substantial portion of the overall cost. Policymakers will The technologies presented earlier in this chapter will need to consider fleet fuel savings (cost per gallon saved) as significantly reduce fuel costs for fleets and customers. The a parameter in their studies and evaluations. addition of hardware such as turbocompounding, aerody- INDIRECT EFFECTS AND EXTERNALITIES TABLE 6-21 Motor Carrier Marginal Expenses Cost per Cost per Overview Expenses Mile ($) Hour ($) The first part of this chapter presented the direct costs Vehicle-Based and benefits associated with various technology packages Fuel-oil costs 0.634 33.00 aimed at improving the efficiency of medium- and heavy- Truck/trailer lease or purchase payments 0.206 10.72 Repair and maintenance 0.092 4.79 duty vehicles. Capital and O&M costs were identified and Fuel taxes 0.062 3.23 weighed against fuel-saving benefits. Understanding these Truck insurance premiums 0.060 3.12 direct costs and benefits is critical, as the economics of tech- Tires 0.030 1.56 nology implementation are a primary decision attribute for Licensing and overweight-oversize permits 0.024 1.25 manufacturers, carriers, and operators. However, direct costs Tolls 0.019 0.99 and benefits are not the only costs and benefits associated Driver-Based with the application of new technologies. There are also in- Driver pay 0.441 16.59 Driver benefits 0.126 6.56 direct costs, benefits, effects, and externalities (impacts that Driver bonus payments 0.036 1.87 are not put in market terms) that should be addressed. Some of these indirect effects represent unintended consequences Total Marginal Costs 1.73 83.68 associated with technologies or policies designed to spur SOURCE: Adapted from American Transportation Research Institute greater fuel efficiency in medium- and heavy-duty vehicles. (2008).

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0 TECHNOLOGIES AND APPROACHES TO REDUCING THE FUEL CONSUMPTION OF MEDIUM- AND HEAVY-DUTY VEHICLES This part of the chapter presents a number of indirect costs following the introduction of the new, more costly vehicles and benefits including: meeting the standard is referred to as “low-buy.” Such impacts have been observed recently in association with • Fleet turnover effects the adoption of the 2004 and 2007 heavy-duty emission • Ton-miles traveled and the rebound effect standards and their associated price increases. Second, some • Vehicle class shifting by consumers fraction of vehicle owners may simply defer purchasing new • Environmental co-benefits and costs trucks for some period of time, keeping their older vehicles • Congestion in operation longer than they would have otherwise. The net • Safety impacts impact of these altered purchasing patterns is to delay the full • Incremental weight effects impact of any new standards that entail notable incremental • Manufacturability and product development. costs. Figure 6-2 shows sales of Class 8 trucks from 1990 to 2007. The committee identified these indirect costs and benefits Truck sales are highly cyclical, responding to general as important to discuss, although the committee recognizes economic conditions. As Figure 6-2 suggests, however, pre- this is not an exhaustive list. Assessment of possible indirect buy behavior can alter somewhat the pattern of sales. In par- effects during policy development will help avoid or mitigate ticular, there appears to be a general industry consensus that negative unintended consequences. the sizable peak in 2006 were largely attributable to pre-buy behavior in advance of more stringent and costly NOx and PM standards being introduced in the following years. The Fleet Turnover Effects size of the peak appears to roughly correspond to the size The implementation of regulations that increase the capi- of the incremental cost increase for the new standard—from about $1,000 for the 2004 standard12 to between $7,000 and tal costs of new vehicles could have an effect on consumer purchase decisions, especially when access to capital is lim- $10,000 for the 2007 standards. ited. In particular, instead of purchasing a new (more expen- An economic analysis of pre-buy and low-buy impacts sive) vehicle, consumers may likely choose to maintain their for Class 8 trucks between 2005 and 2008 (NERA, 2008) existing vehicle in order to extend its life. If these existing utilized a vehicle scrap model along with a price elasticity model to predict increases and decreases in annual sales.13 vehicles are less efficient than new ones, the overall effect of the regulation may be dampened or even counterproduc- The model was relatively successful in predicting pre-buy tive. The issue of how new technologies and regulations increases although somewhat less successful in predicting will affect new vehicle prices and operating costs—and the low-buy decreases. impact on fleet turnover from those cost effects—is an area Both the NERA modeling exercise and subsequent data that needs further analysis. also showed that the low-buy “dip” was actually more The purchase of new medium- and heavy-duty vehicles substantial than the pre-buy “peak” by a ratio of about 3 to is a capital-intensive prospect. For example, the latest Class 2, meaning that there was a net decrease in sales over this 8b tractor rigs commonly cost more than $100,000 (CARB, period. A net downturn in sales also indicates that a portion 2008). In addition, the adoption of efficiency improvement of vehicle owners may be keeping their older units on the strategies such as aerodynamic retrofits or advanced engine road longer (assuming freight demand levels do not decrease designs, as shown in Tables 6-18 and 6-19, can add thousands substantially). The aggregate impact of all of these factors of dollars to the cost of a truck. Accordingly, incremental was estimated to result in a net increase in national annual vehicle cost increases associated with new fuel economy NOx emissions in 2010 of more than 50,000 tons, relative to (or other) standards combined with truck owner budget the case without pre-buy/low-buy and elasticity effects. This constraints are likely to impact truck purchasing decisions represents about 1 percent of expected NOx emissions from all on-road sources.14 at the fleet level. The impact of increasing new vehicle purchase and oper- Although not identical to the situation presented by a ating costs will likely be twofold. First, some vehicle owners potential fuel efficiency standard, where some or all of the may decide to accelerate their purchase schedule, obtaining a incremental vehicle cost may eventually be recouped through new vehicle before the adoption of a new standard, thereby future fuel savings, buyer responses to the cost increases as - deferring the incremental cost of the standard until their next sociated with previous NOx and PM standards could provide purchase cycle. Buyers may also be concerned about the reliability of unproven technology, further increasing their 12 The 2004 heavy-duty engine standards actually began to penetrate incentive for early purchases. This approach also allows the market at substantial levels in 2003 as a result of the consent decree truck buyers to observe the performance of the new technol- pull-ahead. 13 The elasticity model assumed a 1 percent increase in sales price trans - ogy secondhand, without incurring the associated risk. lated to a 1.9 percent decrease in sales. Such early purchase behavior is referred to as “pre-buy.” 14 See http://www.epa.gov/ttn/chief/trends/index.html for national emis - The associated dip in purchases in the time immediately sion inventory trends.

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 COSTS AND BENEFITS OF INTEGRATING FUEL CONSUMPTION REDUCTION TECHNOLOGIES truck fuel savings. This effect is the so-called rebound effect and has been measured in many statistical studies pertain- ing to the light-duty vehicle fleet. Regulations that lead to increases in costs will have the opposite effect. Number (1000s) In light-duty vehicles the studies measure the increased driving that occurs in reaction to the reduction in the variable cost of driving a mile as a result of the application of fuel- saving technologies. In medium- and heavy-duty trucking, this “rebound” is a more complex phenomenon and has been studied less than the light-duty vehicle effect. The problem can be conceptualized as follows. If invest- ment in new technology is cost effective as seen by the pri- vate firm, and lowers the cost of truck transport, two types of FIGURE 6-2 New retail Class 8 truck sales, 1990-2007. SOURCE: reactions would be expected. First, lower costs in this very TRB (2009). 6-2 New retail class 8 truck sales.eps Figure competitive industry are likely to be passed on to shippers as bitmap--legibility degraded a rough sense of the possible pre-buy and low-buy impacts lower prices. The lower prices will reduce delivered prices associated with future fuel efficiency regulations. of freight, which to some degree will lead to higher demand In addition to pre-buy influences, other factors can have for the products being shipped and hence more shipments. a confounding effect on vehicle purchasing behavior, mak- Over a long term the cost of shipping will affect decisions ing it difficult to predict sales changes on a consistent basis. on production and distribution center locations, which will NERA notes other factors influencing sales prices, includ- also affect the demand for trucking services. In addition, ing fluctuations in steel prices. The likelihood of keeping the lower cost of shipping by truck relative to other modes, an older vehicle on the road longer will also involve deci- particularly rail, will lead to more freight being diverted from sions about resale markets, variable O&M costs, and future rail to being shipped by truck. demand levels. In fact, the California Air Resources Board If the application of technology pushes beyond the pri- has concluded that predicted economic activity in the trans- vate cost-effective level, and the costs of shipping increase, portation sector is by far the most important determinant the response will be the reverse—higher costs will reduce impacting heavy-duty vehicle purchase decisions. From this shipments by truck. This case may be socially efficient if perspective, much of the “low-buy” in heavy truck sales in the higher cost is truly reflecting the additional social costs 2007 may actually be due to the general economic down- of climate change and oil security due to fuel consump - turn rather than a retreat from pre-buy expenditures. More tion—costs that are difficult to determine. In this case the research is needed to explore this effect. goal of the standard is to push technology adoption beyond In summary, during periods of stable or growing demand the point a purely private decision would take it. in the freight sector, pre-buy behavior may have a significant The aggregate effects of truck costs on the demand for impact on purchase patterns, especially for larger fleets with shipping are summarized statistically by the own-price better access to capital and financing. Under these same elasticity of trucking. The own-price elasticity measures the conditions, smaller operators may simply elect to keep their total percentage increase in the demand for shipments rela- current equipment on the road longer, which is all the more tive to the percentage change in the price of shipping. The likely given continued improvements in diesel engine dura- modal-shift response, which is part of the total response, is bility over time. On the other hand, to the extent that fuel summarized statistically by the cross-price elasticity. The economy improvements can offset incremental purchase cross-price elasticity measures the percentage change in rail costs, these impacts will be lessened. Nevertheless, when shipments for a given percentage change in truck shipping it comes to efficiency investments, most heavy-duty fleet rates. operators require relatively quick payback periods, on the Studies measuring own-price and cross-price elasticities order of 2 to 3 years. As such, pre-buy effects may still be a have concentrated on long-haul freight movements since factor impacting the pace of new technology introduction. these movements are most subject to intermodal competi- tion, represent a significant fraction of freight movement, and account for 78 percent of fuel consumed by medium- and Ton-Miles Traveled and the Rebound Effect heavy-duty trucks. The results of these studies range widely, To understand the aggregate systemwide effect on fuel depending on the type of product being shipped, the geogra - consumption, not only must the effect of fuel-saving mea- phy of the shipments, trip lengths, and the specific functional sures on fuel consumption per ton-mile be considered, but form used to describe the relationship. In addition, some also whether fuel consumption improvements reduce or raise studies measure the effect on tons shipped, and some mea- total operating costs. Reductions in cost will lead to truck sure the effect on ton-miles or volume. A literature survey traffic increases, thereby partially offsetting the individual by Christidis and Leduc (2009) reported elasticity estimates

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 TECHNOLOGIES AND APPROACHES TO REDUCING THE FUEL CONSUMPTION OF MEDIUM- AND HEAVY-DUTY VEHICLES from eight studies mostly in the range of −0.5 to −1.5. A (namely NOx and PM) during this period. Another example second survey (Graham and Glaister, 2004) also cites a likely occurs when engine loads are reduced (e.g., through adoption range of −0.5 to −1.5 for the own-price elasticity, although of aerodynamic or rolling resistance improvements), which it does not specify if that is for tons or ton-miles. A recent in turn reduce NOx emissions (Schubert and Kromer, 2008). study by the Federal Highway Administration (FHWA) used Table 6-23 demonstrates trade-offs between fuel efficiency technologies and engine-out NOx emissions.15 own-price elasticity for ton-miles of –0.97, meaning that a 1 percent increase in the price of shipping one ton over In interpreting Table 6-23, it is important to note that all one mile results in slightly less than a 1 percent reduction engines have to meet stringent NOx and PM standards at in ton-miles shipped. A study for the National Cooperative certification. In addition, new 2007-2010 exhaust emissions Highway Research Program cited a rail cross-price elasticity standards effectively require aftertreatment technologies of 0.52 based on the intermodal competition model and iden- (SCR and PM traps) that will substantially reduce engine-out tified a range of cross-price elasticities of 0.35 to 0.59 from emissions prior to exhaust. Therefore, although trade-offs an analysis of Class 1 railroads (Dennis, 1988; Jones et al., exist between engine efficiency improvements and engine- 1990). Given the wide range of estimates and the impreci- out emissions, any engine modifications to improve fuel sion of the demand variables, it is not possible to provide a efficiency must ultimately comply with emission standards confident measure of the rebound effect. at certification and during in-use operation. In fact, the com- mittee expects that new NOx control technologies such as SCR will be so effective in reducing tailpipe emissions as to Vehicle Class Shifting by Consumers potentially allow engine manufacturers to increase engine When manufacturers build vehicles, they make trade-offs efficiency while still complying with emission standards. related to various vehicle attributes in order to produce a vehicle that is most attractive to a given market segment. For Congestion example, manufacturers regularly need to balance issues of performance, cost, and fuel efficiency. In cases where regu- Traffic congestion has increased dramatically throughout lation incentivizes a certain class of vehicles to meet a fuel the world due to increased vehicle miles traveled and can efficiency standard at the expense of performance, a potential result in significant loss of time, money, and fuel. Travel in buyer may choose to purchase a larger class vehicle to offset congested conditions results in both longer and less predict- the performance losses. This behavior would lead to less able travel times. The Texas Transportation Institute (TTI) efficient vehicles on the road—exactly the opposite effect estimated that in 2007 the 439 urban areas in the United of what an efficiency standard is designed to achieve. This States experienced 4.2 billion vehicle-hours of delay, result- behavior can be called “consumer class shifting.” Class shift- ing in 2.8 billion gallons of wasted fuel and $87.2 billion in ing could also occur if the cost of different vehicle classes is delay and fuel costs (Schrank and Lomax, 2005). TTI (2007) affected disproportionately by the regulations. For example, also found that the commercial vehicle cost of congestion, requiring aerodynamic fairings on all Class 8 vehicles may in both lost time and fuel, was ~$77 per vehicle-hour. The cause some companies that currently use these vehicles on major causes of traffic congestion in the United States, as a long-haul operations to choose smaller, less efficient vehicles percentage of total congestion, are (1) bottlenecks (traffic rather than invest in the fairings. Others, however, will find demand exceeds roadway capacity)—50 percent; (2) traffic they will have to add fairings that provide little benefit at incidents—25 percent; (3) work zones—15 percent; (4) bad high cost. weather—10 percent; and (5) poor signal timing—5 percent There is little or no literature that describes the cross-class (AHUA, 2004). There are two questions. First, if regulations mode shift between truck types based on cost or performance, increase truck VMT, what are the potential implications for although at least one manufacturer interviewed for this report congestion? Second, if regulations cause degradation in truck expressed consumer class shifting as a concern (particularly performance, will slower trucks, or trucks with reduced hill- for lower class vehicles). To induce consumer class shifting, climbing ability, cause congestion to increase? regulations would need to significantly increase the cost or This chapter identifies how the demand for long-haul decrease the performance of one class of trucks relative to trucking could increase if regulations on reducing fuel another. consumption effectively reduce the net operating cost of long-haul trucking (i.e., the “rebound effect”). The effect on demand for trucking services is shown to be potentially Environmental Co-Benefits and Costs significant, depending on the technology chosen and the It is often (but not always) the case that fuel efficiency own-price and cross-price elasticities of demand. There is improvements result in reductions of other pollutants as well. 15A primary cause for the trade-off between fuel consumption and engine- Certain technologies such as hybridization or idle reduction out NOx emissions is that NOx formation is highly temperature dependent; reduce the amount of time an internal combustion engine therefore, at high combustion temperatures (which generally result in high is operating, resulting in a direct reduction in all emissions pressures and thermal efficiency), NOx formation increases.

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 COSTS AND BENEFITS OF INTEGRATING FUEL CONSUMPTION REDUCTION TECHNOLOGIES TABLE 6-23 Fuel Efficiency Technology Versus NOx increase the number of PCEs for a single truck. Truck PCE conversions are necessary to calculate a volume-to-capacity Emissions Trade-off (V/C) ratio, which can be used to estimate congestion and Fuel Efficiency Effect on delay measurement. Technology Efficiency Effect on NOx While different formulas have been developed to estimate Aerodynamic/weight +/++++ Anticipated decrease, depending traffic speeds based on V/C ratios, an illustrative example can reduction on mode be provided through the use of the Bureau of Public Roads Variable valve actuation + Depends on design formula: Higher cylinder pressure ++ Increases proportionally Miller cycle +++ May decrease due to aftercooling Multistage turbo ++ Increases if EGR cannot be used FFS CS = Mechanical + Minimal  V  4 turbocompound 1 + 0.15    C  Electrical ++ Minimal  turbocompound Bottoming cycle ++++ Minimal Thermoelectrics + Minimal where CS is congestion speed, FFS is free-flow speed, V Enhanced exhaust Minimal Minimal is volume of traffic, and C is traffic volume capacity. The insulation formula implies that as a basic freeway segment approaches Hybridization +++ Reduction capacity (as the V/C ratio approaches 1.0), traffic speed will Idle reduction ++++ Reduction be reduced. To calculate delay, both congested and free-flow travel times must be calculated from the segment length and congested and free-flow speeds and then the difference between the free-flow travel time and the congested travel time must be measured. little information, however, about effects of potential perfor- An alternative perspective on congestion measurement mance degradation, although, where present, they may result uses estimates from the literature on the marginal cost of in locally significant effects on congestion. one combination truck on overall congestion. Parry (2006) The remainder of this section focuses on basic freeway estimates the marginal congestion cost of combination trucks segments and is applied to the heavier, slower trucks (Classes to be $0.168 per mile in urban areas and $0.037 per mile in 4 through 8). Trucks have an impact on congestion at other rural areas. The marginal congestion cost describes the cost, traffic control locations, such as signalized and unsignalized measured in lost travel time, that a single additional combi- intersections, merge sections, and freeway-to-freeway off- nation truck imposes on the rest of the traffic already on the ramps, but the data to analyze these impacts are not readily roadway. Generally, as congestion increases, the marginal available. In the highway capacity manual (HCM), in basic cost increases. freeway analysis, trucks are represented as “passenger car equivalents” (PCE; TRB, 2000). The PCE concept is meant to capture the effect that heavy vehicles have on traffic flow Safety Impacts on a freeway because heavy vehicles occupy more space, New regulations that would affect fuel efficiency of me- travel more slowly up steep grades and more quickly down dium- and heavy-duty vehicles must consider impacts on them, accelerate more slowly, brake more slowly, and change vehicle and highway safety. The safety impacts are of several lanes more slowly than passenger cars. Furthermore, differ- types. First, new technologies may have specific safety is- ent passenger car operators react differently to the presence sues associated with them. For example, hybridization will of trucks, for example, following farther behind trucks than introduce high-voltage electrical equipment into trucks; cars. operators, service mechanics, and emergency personnel The HCM increases the PCE for trucks based on road- will need to be educated about appropriate handling of this way conditions such as grade, number of lanes, distance equipment. Second, the rebound effect may increase overall to roadside obstructions, and width of lanes. It does not, truck traffic on the road, thereby leading to potentially higher however, distinguish between truck PCEs under congested incidences of accidents. Third, some technologies and/or and uncongested conditions. FHWA simulated the effect approaches to improving fuel efficiency may actually lead of combination trucks as part of its truck size and weight to a safer highway system; for example, speed reductions, study to estimate how effective truck PCEs change based improved driver training, and use of side fairings might re- on the weight-to-horsepower ratio of the truck itself, grade duce hazards to other vehicles in inclement weather. Fourth, of the roadway, road type, geography, and congestion lev- if new technologies diminish the performance of vehicles els. FHWA did not estimate the impacts of other roadway (e.g., decrease acceleration times), negative safety impacts characteristics such as lane width or distance to obstruc- could occur. Lastly, if new technologies or regulations have tions (Battelle, 2005). Generally, steeper grades, longer the effect of increasing payload capacity for trucks, fewer hills, fewer lanes, and a higher weight-to-horsepower ratio

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 TECHNOLOGIES AND APPROACHES TO REDUCING THE FUEL CONSUMPTION OF MEDIUM- AND HEAVY-DUTY VEHICLES TABLE 6-24 Estimated Costs for Crashes Involving trucks may be in operation, potentially resulting in safety benefits. Of these five types of safety issues, only the second Truck Tractor with One Trailer, 2006 one (safety issues related to a rebound effect is discussed in Severity of Crash Estimated Crash Cost ($) detail here). A more detailed assessment would be needed on Crashes with injury 200,000 all these safety aspects based on the type of regulation that Fatal crashes 3,800,000 may be put forward by the U.S. Department of Transporta- tion (DOT). NOTE: Weighted average calculated from the three injury categories presented in Table 2 in Zaloshnja and Miller (2006): “possible injury,” This chapter has described how the demand for long-haul “nonincapacitating injury,” and “incapacitating injury.” trucking will increase if fuel economy regulations effectively reduce long-haul truck operating costs. Truck traffic could increase by 2.2 to 10.5 percent, depending on the technology alternatives and assumed demand elasticities. The literature porting the extra weight itself increases fuel costs, partially shows that truck traffic has a direct correlation with injuries offsetting the fuel savings the technologies allow. This effect and fatalities. Estimates of increased truck traffic can be mul- was discussed in Chapters 4 and 5. tiplied by the injury and fatality crash rates to estimate the Second, in medium-duty truck applications, the extra range of potential deaths and injuries caused by an increase weight may increase the loaded gross weight of some present in travel. Regulations that push beyond the private cost-ef- Class 2 vehicles to over 10,000 lb and of some present Class fective levels of fuel savings can result in a decline in VMT, 6 vehicles to more than 26,000 lb. Surpassing these weight and the effect would be a decline in crash rates. thresholds will subject drivers and companies operating the Recent data for highway crashes indicate crash rates for vehicles to federal and state motor carrier safety regulations. truck tractors with trailers of 2.4 per 100 million VMT for The federal regulations apply to vehicles over 10,000 lb in fatal crashes and 51.1 per 100 million VMT for injury crashes commercial use that operate across state lines. Operators are (Federal Motor Carrier Safety Administration, 2007). To the required to register with DOT. The regulations cover record extent that regulations or technologies incentivize increased keeping, driver qualifications, driver hours of service, safety VMT, accidents and fatalities could potentially increase; in equipment, and other practices (Federal Motor Carrier Safety contrast, if regulations or technologies decrease VMT, ac- Administration, 2008). Many states have adopted similar cidents and fatalities could potentially decrease. regulations for vehicles used intrastate. Drivers operating To estimate the dollar costs from these additional crashes, a vehicles over 26,000 lb must have a commercial drivers Federal Motor Carrier Safety Administration-commissioned license (CDL) that meets federal standards. study on the costs of medium and large truck crashes was used A truck operator who has not previously been subject to (Zoloshnja and Miller, 2006). This study provides estimates these motor carrier safety regulations or to CDL require- of unit costs for highway crashes involving medium/heavy ments and is considering whether to adopt new vehicles trucks by severity. Crash costs are broken out by truck with fuel-saving technologies and higher weight that would type and severity of the crash, including no injury crashes, trigger the regulations will have several options. The opera- crashes with nonfatal injuries, and crashes with a fatality. tor may acquire the heavier vehicles and comply with the The injury costs represent the present value, computed at a 4 regulations or specify offsetting weight-saving equipment in percent discount rate, of all costs over the victims’ expected order to stay under the threshold, or acquire smaller trucks life span that result from a crash. They include medically than previously used. Vehicle manufacturers may decide related costs, emergency services costs, property damage to market new vehicle designs that facilitate the latter two costs, lost productivity, and the monetized value of the pain, choices. Any of these choices will increase the operator’s suffering, and quality of life that the family loses because of truck transportation costs, and the operator will select the one a death or injury. As expected, fatal crashes cost more than with the least cost. Complying with the safety regulations any other crashes. The cost estimates exclude mental health may have benefits to the operator and to society that at least care costs for crash victims, roadside furniture repair costs, partially offset compliance costs. cargo delays, earnings lost by family and friends caring for Finally, in heavy-duty operations in which trucks are the injured, and the value of schoolwork lost. Table 6-24 sometimes loaded to the 80,000-lb legal gross weight limit shows the study findings for one truck type and severity of that applies on most major U.S. roads, and in operations in the crash. The crash costs by severity for “truck tractor and which trucks are sometimes loaded to axle weight limits one trailer” can be used to estimate the costs resulting from (e.g., refuse haulers, dump trucks), the added weight of some the additional crashes. fuel-saving devices (without concomitant vehicle weight- reducing materials) will reduce cargo capacity, increasing av- Effects of Incremental Changes in Weight erage cost per ton-mile and necessitating more vehicle-miles of travel to carry a given quantity of freight. In an operation Certain fuel-saving technologies will add to vehicle in which trucks are almost always loaded to the gross weight weight, affecting operators’ costs in three ways. First, trans-

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 COSTS AND BENEFITS OF INTEGRATING FUEL CONSUMPTION REDUCTION TECHNOLOGIES or axle weight limit, the added cost will be proportional to the eral manufacturers suggested that the larger challenge was loss of payload. For example, the payload of a truck loaded aligning new technology deployment with their product near the 80,000-lb limit is about 50,000 lb, so an additional development process (PDP) or cycle. The opportunities to 500 lb of fuel-saving devices would reduce capacity by 1 integrate new technology designs into a PDP are limited, and percent and increase average cost per ton-mile by 1 percent sufficient time is needed for design and validation, customer in an application in which trucks are usually loaded to the acceptance, testing, and compliance strategy development. In gross weight limit. Fuel savings from the devices would at addition, fuel consumption reduction technologies must be least partially offset this cost increase. integrated with emission and safety technologies in compli- Most large trucks on the road are not loaded to the gross ance with regulations. weight or axle weight limits. For example, 70 percent of traffic of five-axle tractor semitrailer mileage is at gross FINDINGS AND RECOMMENDATION weights below 70,000 lb. For operations in which trucks are never or rarely loaded to the gross or axle weight limits, the Direct Costs and Benefits loss of cargo weight capacity would not affect costs. For a Finding 6-1. Since tractor-trailer trucks have relatively high typical fleet that operates sometimes at the weight limit and sometimes below, costs would be intermediate between the fuel consumption, very high average vehicle miles traveled, two extreme cases. and a large share of the overall truck market, it makes sense Fuel-saving technologies that add weight include the to put a priority on fuel consumption reduction. A given per- following: centage reduction in this vehicle category will save more fuel than a matching percent improvement in any other vehicle • Engine efficiency improvements: turbocompound category. In fact, the potential fuel savings in tractor-trailer systems and waste heat recovery systems trucks represents about half of the total possible fuel savings • Hybrid power systems in all categories of medium- and heavy-duty vehicles. • Aerodynamic fairings Finding 6-2. The fuel consumption reduction potential for In hybrid systems the added weight of batteries and other the tractor-trailer application, in the 2015 to 2020 time frame, components may not be offset by downsizing of the internal is 50.5 percent at a cost of $84,600, which results in a capital combustion engine. European manufacturers report payload cost per percent reduction (CCPPR) of $1,674 per percent penalties of 100 to 200 kg for their medium-duty truck hy- fuel consumption reduction. brids (Baker et al., 2009). One manufacturer of aerodynamic Finding 6-3. The fuel consumption reduction potential for fairings reports that its trailer underside fairings weigh 150 to 230 lb and a trailer rear fairing 75 lb (Freight Wing, no Class 6 box and bucket trucks, in the 2015 to 2020 time date; Transport Canada, 2009). A complete aero package frame, is 47.1 percent for box trucks and 49.6 percent for might add 500 lb. bucket trucks. The resulting cost for box trucks is $43,120 with a CCPPR of $915 per percent fuel saved, and the cost for bucket trucks is $49,870 with a CCPPR of $1,005 per Manufacturability and Product Development percent fuel consumption reduction. As a final note, the committee was tasked to determine Finding 6-4. The fuel consumption reduction potential whether the fuel consumption reduction technologies dis- cussed throughout this report could be efficiently integrated for the Class 2b pickup and van application, in the 2015 to into the manufacturing process. The committee found no 2020 time frame, is 44.5 percent at a cost of $14,710, which current studies or analyses suggesting that manufactur- results in a CCPPR of $331 per percent fuel consumption ability was a major barrier to the integration of gas/diesel reduction. engine, hybrid, aero, tire, or other technologies in the ehicle Finding 6-5. The fuel consumption reduction potential for manufacturing process. (Note: There may still be issues and barriers related to the aailability and manufacturing of the the refuse truck, in the 2015 to 2020 time frame, is 38.4 technologies themselves.) This finding was examined and percent at a cost of $50,800, which results in a CCPPR of reinforced during the committee’s site visits to engine, chas - $1,323 per percent fuel consumption reduction. sis, truck, bus, hybrid, trailer, and other manufacturers/users, Finding 6-6. The fuel consumption reduction potential for including Allison Transmission, ArvinMeritor, Cummins, Great Dane, Ford, Eaton, Enova, WalMart, Navistar, Azure, transit bus applications, in the 2015 to 2020 time frame, is Peterbilt, and PACCAR. These manufacturers were familiar 47.8 percent at a cost of $250,400 (without subsidy), which with the technologies that could be introduced during the results in a CCPPR of $5,232 per percent fuel consumption 2010-2015 time period, and they did not see any significant reduction. issues for their manufacturing processes. However, sev-

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 TECHNOLOGIES AND APPROACHES TO REDUCING THE FUEL CONSUMPTION OF MEDIUM- AND HEAVY-DUTY VEHICLES Finding 6-7. The fuel consumption reduction potential for Finding 6-10. Consumer buying in anticipation of new the motor coach application, in the 2015 to 2020 time frame, regulations (pre-buy) and retention of older vehicles can is 32 percent at a cost of $36,350, which results in a CCPPR slow the rate of fleet turnover and the rate at which regulatory of $1,136 per percent fuel consumption reduction. standards can affect fleetwide fuel consumption. The com- mittee believes the effects will be transient and reduced to Finding 6-8. Table 6-25 summarizes, for the seven ve - the extent that fuel consumption savings offset incremental hicle applications studied, the fuel consumption reduction purchase costs. Government incentives in the form of tax potential (from Chapters 4 and 5), the capital cost, and the credits or excise tax reductions with a sunset date could be cost-benefit for the 2015 to 2020 time frame, as stated in used to help minimize anticipated pre-buy/low-buy fluctua- Findings 6-2 to 6-7. tions in the future. Regulators must be cognizant of these potential effects and should consider regulatory mechanisms that minimize these potential distortions. TABLE 6-25 Summary of Potential Fuel Consumption Reduction, Cost, and Cost-Benefit Finding 6-11. Elasticity estimates vary over a wide range, Cost-Effectiveness Metric and it is not possible to calculate with a great deal of con- fidence what the magnitude of the “rebound” effect is for Dollars Dollars Fuel per per Breakeven heavy-duty trucks. The rebound effect measures the increase Consumption Capital Percent Gallon Fuel in ton-miles shipped resulting from a reduction in the cost Pricea Reduction Cost Fuel Saved of shipping. A rebound effect nevertheless likely exists that Vehicle Class (%) ($) Saved per Year ($/gal) will partially offset fuel consumption declines due to the Tractor-trailer 51 84,600 1,674 7.68 1.09 adoption of new cost-effective technologies. To the extent Class 6 box 47 43,120 915 29.30 4.17 the regulation pushes beyond the private cost-effective point, truck the rebound effect will be reversed. Estimates of fuel savings Class 6 bucket 50 49,870 1,006 37.80 5.38 truck from regulatory standards will be somewhat misestimated if Class 2b pickup 45 14,710 331 33.73 4.81 the rebound effect is not considered. Refuse truck 38 50,800 1,323 18.90 2.69 Transit bus 48 250,400 5,232 48.05 6.84 Finding 6-12. Standards that differentially affect the capital Motor coach 32 36,350 1,135 11.59 1.65 and operating costs of individual vehicle classes can cause NOTE: Values shown are for one set of input assumptions. Results will vary purchase of vehicles that are not optimized for particular depending on these assumptions. operating conditions. The complexity of truck use and the aCalculated assuming a 7 percent discount rate and a 10-year life, ex - variability of duty cycles increase the probability of these cluding incremental operating and maintenance costs associated with the technologies. unintended consequences. SOURCE: Adapted from TIAX (2009). Finding 6-13. Reduced fuel consumption through fuel ef- ficiency technologies in medium- and heavy-duty vehicles The tractor trailer offers the best cost-benefit potential, will likely reduce emissions of criteria pollutants. Efficiency followed by the motor coach. The refuse hauler costs more improvements achieved by improved aerodynamics, tire roll- than twice as much per gallon of fuel saved, and the other ing resistance, and weight reductions will translate into lower vehicle classes are even more expensive. tailpipe emissions as well. Finding 6-14. To the extent that regulations alter the number Indirect Costs and Benefits of shipments and VMT, there will be some safety and conges- Finding 6-9. A number of indirect effects and unintended tion impacts. A more detailed assessment of these impacts consequences associated with regulations aimed at reducing would be needed based on the type of regulation that may be fuel consumption in the trucking sector can be important. In put forward by the U.S. Department of Transportation. particular, regulators should consider the following effects in Finding 6-15. There are potential safety issues associated the development of any regulatory proposals: rate of replace- ment of older vehicles (fleet turnover impacts), increased with particular fuel reduction technologies. Examples are ton-miles shipped due to the lower cost of shipping (rebound hybrids that use high-voltage batteries or aerodynamic fair- effect), purchasing one class of vehicle rather than another ings that may detach from trucks on the road. in response to a regulatory change (vehicle class shifting), Finding 6-16. Some fuel-efficienc-improving technologies environmental co-benefits and costs, congestion, safety, and incremental weight impacts. will add weight to vehicles and push those vehicles over federal threshold weights, thereby triggering new operational

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 COSTS AND BENEFITS OF INTEGRATING FUEL CONSUMPTION REDUCTION TECHNOLOGIES conditions and affecting, in turn, vehicle purchase decisions. Christidis, Panavotis, and Guillaume Leduc. 2009. Longer and Heavier Ve- hicles for Freight Transport. JRCC52005. European Commission Joint More research is needed to assess the significance of this Research Center, Institute for Prospective Technology Studies. potential impact. Cooper, C. 2009. Reducing Heavy-Duty Long Haul Combination Truck Fuel Consumption and CO2 Emissions. Boston: NESCCAF. Finding 6-17. Some fuel-efficiency-improving technolo- Dennis, Scott M. 1988. The Intermodal Competition Model. Association of gies will reduce cargo capacity for trucks that are currently American Railroads. September. DOE (U.S. Department of Energy), Energy Information Administration “weighed out” and will therefore force additional trucks onto (EIA). 2009. Assumptions to the Annual Energy Outlook 2009. Avail- the road. More research is needed to assess the significance able at http://www.eia.doe.gov/oiaf/aeo/assumption/transportation. of this potential impact. html. EPA (U.S. Environmental Protection Agency). 2006. Motor Coach Idling Finding 6-18. The committee found no current studies Field Observation Study for Washington, DC, Metro Area. Trans - portation and Regional Programs Division and SmartWay Transport or analyses suggesting that manufacturability was a major Partnership Group, Office of Transportation and Air Quality, U.S. barrier to the integration of gas/diesel engine, hybrid, aero- Environmental Protection Agency. Available at http://epa.gov/smartway/ dynamic, tire, or other technologies in the ehicle manu- documents/420s06004.pdf. facturing process. However, there may be challenges with Federal Motor Carrier Safety Administration. 2007. Commercial Vehicle integrating new technologies into manufacturers’ product Facts. November. 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