3
Review of Current Regulatory Approaches for Trucks and Cars

The industry built around the use, servicing, and manufacture of medium- and heavy-duty vehicles is large and diverse. Manufacturers, for example, produce many customer-specific configurations assembled with components from multiple suppliers. To aid consideration of what part of the industry should be regulated and how regulations could be implemented, this chapter reviews current regulations and certification protocols as they might apply to medium-and heavy-duty truck fuel consumption. Regulations for medium- and heavy-duty truck fuel economy already exist in Japan and are under development in the European Union (EU). In the United States, California has promulgated rules for heavy-duty truck fuel economy based on the SmartWay voluntary program of the U.S. Environmental Protection Agency (EPA). Regulation of the fuel economy of passenger vehicles began in the United States in 1975, building on the emissions certification procedures already in place since the 1960s. Emissions regulations for heavy-duty trucks have been in force since the early 1970s. Because the test procedures and standards have been revised several times, regulators have repeatedly been faced with the challenge of regulating an extremely diverse industry. In addition, regulation of safety cuts across component suppliers and truck assemblers. Other regulations of interest govern truck size and weight, which are covered in Chapter 7.

EUROPEAN APPROACH

In June 2007 the European Commission (EC) began a study to explore test procedures and metrics for measuring fuel consumption and carbon dioxide (CO2) emissions. The study initially focused only on the engine and on efficiencies that could be gained through technologies related to the engine. Through active collaboration with heavy-duty truck manufacturers, the EC began to define a variety of duty cycles for the various vocational uses of such trucks. As a result of the collaborative work, in June 2008 the scope of the study and test procedure was expanded to include the whole vehicle and was planned to include alternative driveline concepts such as hybrids, as well as the aerodynamics of both tractor and trailer, gross combination vehicle weight, loading capacity, rolling resistance, and all other technologies that could be applied to reduce fuel consumption.

The absence of a uniform vehicle size and configuration and the existence of myriad possible duty cycles, however, contribute to an enormous degree of complexity in defining a regulation that can be applied. The result is that a simple “one size fits all” approach to measuring CO2 emissions or fuel efficiency is not feasible. Further, full-vehicle testing of even a fraction of the possible combinations of vehicles and duty cycles would be prohibitively costly.

The absence of uniform vehicles and duty cycles also led the EC to conclude that any metric used should include some indication of the work done as well as the fuel used (e.g., liters of fuel per ton-kilometer).

As a result of the study, the European Automobile Manufacturers Association and the European Council for Automotive R&D have proposed a project to develop a methodology to evaluate the fuel efficiency of heavy-duty vehicles using computer simulation. This will provide a common tool for determining the fuel efficiency and CO2 generation of heavy-duty vehicles, buses, and coaches over a wide range of duty cycles, taking into account the many possible configurations and mission profiles. Figure 3-1 provides an overview of the proposed approach and simulation tool. The program began in 2009 with a projected 4-year timeline, resulting in a fuel economy regulation for the European Union in 2013-2014. It is expected that the truck manufacturer will be the regulated entity, given the widespread integration of truck and engine manufacturers. As is evident in Figure 3-1, the EC is considering a work-based metric of fuel consumed per payload mass, payload volume, or number of passengers carried per distance traveled.



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3 Review of Current Regulatory Approaches for Trucks and Cars The industry built around the use, servicing, and manu- scope of the study and test procedure was expanded to facture of medium- and heavy-duty vehicles is large and include the whole vehicle and was planned to include al - diverse. Manufacturers, for example, produce many cus- ternative driveline concepts such as hybrids, as well as the tomer-specific configurations assembled with components aerodynamics of both tractor and trailer, gross combination from multiple suppliers. To aid consideration of what part of vehicle weight, loading capacity, rolling resistance, and the industry should be regulated and how regulations could all other technologies that could be applied to reduce fuel be implemented, this chapter reviews current regulations consumption. and certification protocols as they might apply to medium- The absence of a uniform vehicle size and configuration and heavy-duty truck fuel consumption. Regulations for and the existence of myriad possible duty cycles, however, medium- and heavy-duty truck fuel economy already exist contribute to an enormous degree of complexity in defining in Japan and are under development in the European Union a regulation that can be applied. The result is that a simple (EU). In the United States, California has promulgated rules “one size fits all” approach to measuring CO2 emissions or for heavy-duty truck fuel economy based on the SmartWay fuel efficiency is not feasible. Further, full-vehicle testing of voluntary program of the U.S. Environmental Protection even a fraction of the possible combinations of vehicles and Agency (EPA). Regulation of the fuel economy of passenger duty cycles would be prohibitively costly. vehicles began in the United States in 1975, building on the The absence of uniform vehicles and duty cycles also led emissions certification procedures already in place since the EC to conclude that any metric used should include some the 1960s. Emissions regulations for heavy-duty trucks indication of the work done as well as the fuel used (e.g., have been in force since the early 1970s. Because the test liters of fuel per ton-kilometer). procedures and standards have been revised several times, As a result of the study, the European Automobile Manu- regulators have repeatedly been faced with the challenge of facturers Association and the European Council for Automo- regulating an extremely diverse industry. In addition, regu- tive R&D have proposed a project to develop a methodology lation of safety cuts across component suppliers and truck to evaluate the fuel efficiency of heavy-duty vehicles using assemblers. Other regulations of interest govern truck size computer simulation. This will provide a common tool for and weight, which are covered in Chapter 7. determining the fuel efficiency and CO2 generation of heavy- duty vehicles, buses, and coaches over a wide range of duty cycles, taking into account the many possible configurations EUROPEAN APPROACH and mission profiles. Figure 3-1 provides an overview of the In June 2007 the European Commission (EC) began a proposed approach and simulation tool. The program began study to explore test procedures and metrics for measuring in 2009 with a projected 4-year timeline, resulting in a fuel fuel consumption and carbon dioxide (CO2) emissions. The economy regulation for the European Union in 2013-2014. It study initially focused only on the engine and on efficien - is expected that the truck manufacturer will be the regulated cies that could be gained through technologies related to entity, given the widespread integration of truck and engine the engine. Through active collaboration with heavy-duty manufacturers. As is evident in Figure 3-1, the EC is con- truck manufacturers, the EC began to define a variety of sidering a work-based metric of fuel consumed per payload duty cycles for the various vocational uses of such trucks. mass, payload volume, or number of passengers carried per As a result of the collaborative work, in June 2008 the distance traveled. 

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 TECHNOLOGIES AND APPROACHES TO REDUCING THE FUEL CONSUMPTION OF MEDIUM- AND HEAVY-DUTY VEHICLES INPUT: VEHICLE MODULES Chassis or combination Power train specification, Rolling A ir specification, Engine Gear ECO weight resistance resistance Auxiliaries hybrids map box equipment COMMON CORE SIMULATION PROCESSOR FIGURE 3-1 Overview of simu- Mission (Speed, Road, Driver Climate Fuel lation tool and methodology pro- Load factors Traf fic…) posed for use in the European INPUT: TRANSPORT TASK MODULES Union. Both inputs and results are declared transparently. SOURCE: Stefan Larsson, European Auto Input modules could be standardized, generic, or specific according to application purpose. Manufacturers, presentation to the With standardized interfaces to the core processor, input modules could be developed and improved committee. over time. Figure 3-1 Overview of simulation tool and FORTRAN and C++, allows us- software, available in both methodology propo.eps JAPANESE APPROACH ers to modify the transmission ratio, the final drive ratio, the Regulation of fuel consumption in Japan is directly linked wheel radius, and the main engine characteristics (including to Japan’s commitment under the Kyoto Protocol to reduce wide-open-throttle and closed-throttle torque curves as well greenhouse gases.1 In Japan, heavy-duty trucks account for as fuel rate map). However, it forces most of the remaining 25 percent of the greenhouse gases generated by automotive parameters to remain constant. As such the vehicle charac- sources. The “Top-Runner Standard” for measuring fuel teristics (weight, frontal area, drag coefficient) or component consumption was started for heavy-duty trucks in 2006, losses (efficiencies) cannot be modified. Moreover, advanced with a target implementation date of 2015. The vehicle shifting control algorithms that might be available cannot manufacturer is the regulated entity. In Japan the engine and be implemented. The impact of active regeneration of diesel heavy-duty vehicle manufacturers are integrated and few in particle filters is handled by calculating the ratio of vehicles number, so the point of regulation is more obvious than in with this feature to those without it (Sato, 2007). Overall, the United States. the tool allows evaluation of new engine technologies while As in Europe, the process began with collaborative keeping the rest of the power train and vehicle unchanged. meetings with the heavy-duty truck manufacturers to col- Finally, only two drive cycles can currently be selected. lect data on vehicles and technologies that could improve Because the Japanese program focuses on engines, new fuel consumption. However, unlike in Europe, the primary methodologies for measurement must be developed as new focus in Japan is on improvements due to changes in engine technologies are introduced to account for their contribu- technology only, rather than to the whole vehicle, and the tion to improving fuel consumption. There is currently no metric used is “kilometers/liter,” with differing standards for provision in the simulations to take these contributions into different weight classes (Figure 3-2). account. Fuel consumption is evaluated through computer simula- Because of the large reductions in fuel consumption tion based on a combination of an urban duty cycle defined a chievable with hybrid electric trucks, a measurement in JE005, used for emissions testing, and an interurban cycle method for this technology was included in the Japanese developed for fuel economy testing. The simulation tool, regulation. To measure the contribution of hybrid technol- which is available online for manufacturers to use, requires ogy, the Japanese developed hardware-in-the-loop simula- vehicle specifications and engine fuel maps as input data. An tion (HILS) testing (Figure 3-5; see also Appendix H) and overview of the simulation methodology is given in Figures used it for measuring emissions, as well as calculating fuel 3-3 and 3-4. consumption. HILS substitutes for the conversion program The vehicle simulation tools used by Japan’s Ministry of (see Figure 3-4) used in the process for nonhybrid vehicles Land, Infrastructure, Transport, and Tourism evaluate the fuel (Morita et al., 2008). Details of the method and validation consumption and performance of conventional vehicles. The are available in Morita et al. (2008). The HILS approach was recently recommended for further study and potentially wider implementation (in Europe and beyond) for hybrid 1The Kyoto Protocol, an international agreement linked to the United vehicles by an international committee of engine and vehicle Nations Framework Convention on Climate Change, sets binding targets manufacturers. for 37 industrialized countries and the European community for reducing greenhouse gas emissions by an average of 5 percent against 1990 levels over the 5-year period 2008-2012.

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 REVIEW OF CURRENT REGULATORY APPROACHES FOR TRUCKS AND CARS Target Standard Values for Trucks Class by 3. 5 7. 5 8 10 12 14 16 20 - GV W ( t) -7.5 -8 -10 -12 -14 -16 -20 Payload ( t ) - 1. 5 1.5 -2 2- 3 3- Target 10.83 10.35 9.51 8.12 7. 24 6.52 6.00 5.69 4.97 4.15 4.04 (km/ L) Target Standard Values for City Buses FIGURE 3-2 Japanese fuel economy Class by -8 8-10 10 -12 12 -14 14 - t argets for heavy-duty vehicles by GV W ( t ) weight class. The target is for fiscal Target 6.97 6.30 5.77 5.14 4. 23 year 2015. SOURCE: Presentation to (km/L ) the committee by Akihiko Hoshi, Min- istry of Land, Infrastructure, Trans- port, and Tourism, Japan. Figure 3-2 Japanese fuel economy targets for heavy-duty....eps Engine E u: Fuel Urban Driving Mode Operating JE05 mode Ef ficiency Mode E : Fuel Combined Ef ficiency Interurban Driving Mode Engine E h: Fuel Operating 80km /h constant speed Ef ficiency Mode mode with gradient E=1 / ( u / Eu + ° h / Eh) ° FIGURE 3-3 J apanese simulation E: Heav y vehicle mode fuel ef ficiency (km/ L) method incorporating urban and inter- Eu: Urban driving mode fuel ef ficiency (km/ L) urban driving modes. SOURCE: Pre- Eh: Interurban driving mode fuel ef ficiency (km/ L) sentation to the committee by Akihiko ° u: Propor tion of urban driving mode Hoshi, Ministry of Land, Infrastruc- ° h: Propor tion of interurban driving mode ture, Transport, and Tourism, Japan. Figure 3-3 Japanese simulation method incorporating urban an.eps U.S. APPROACH: EPA SMARTWAY VOLUNTARY in that some participants include their medium-duty trucks in CERTIFICATION PROGRAM the partnership. Certification allows carriers, manufacturers, and shippers to apply the SmartWay logo (Figure 3-6) to their In 2004 the EPA began development and implementation products as a signal to consumers and the community that of SmartWay, an organized effort to specify a collection they are taking actions to limit the negative environmental of current and emerging technologies for creating efficient impacts of their business operations. tractor-trailer combinations with the best environmental To attain SmartWay certification, tractors must have performance in terms of both air pollution and emission an aerodynamic profile that includes a high roof sleeper, of greenhouse gases. The certification program uses exist- integrated roof fairings, cab side extenders, fuel tank side ing (2007) EPA test methods, supplemented by additional fairings, and aerodynamic bumpers and mirrors (Figure 3-7). testing, available industry test data, and ongoing research. They must be powered by a 2007 or newer engine, with a SmartWay designations are limited to new passenger ve- SmartWay-approved option for idle reduction. The tires must hicles (cars, light trucks, sport utility vehicles, vans), new be SmartWay-approved, low-rolling-resistance tires; the use Class 8 sleeper trucks, new 53-ft dry van trailers, and retrofit of aluminum wheels for weight reduction is an option. The 53-ft dry van trailers but will include other truck types in the tractor specification is a design attribute only. EPA sets no future. The partnership program under SmartWay includes vehicle-level performance targets in SmartWay and requires other types of trucks above 8,500 gross vehicle weight rating,

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 TECHNOLOGIES AND APPROACHES TO REDUCING THE FUEL CONSUMPTION OF MEDIUM- AND HEAVY-DUTY VEHICLES Phase of Urban driving mode Driving mode = conversion Interurban driving mode Speed vs. time Conversion program Vehicle • D etermin e gear-shift positions. specifications Engine sp eed / • Calculate engine sp eed and torque. torque vs. time Fuel ef ficiency Engine Operating Mode map Phase of Engine calculation torque of fuel Torque ( Nm) ef ficiency Computing Engine speed FIGURE 3-4 Japanese simulation method overview. SOURCE: Presentation to the Time ( s) Fuel consumption Engine speed (rpm ) committee by Akihiko Hoshi, Ministry of = *Before simulation, p erform Land, Infrastructure, Transport, and Tour- operation tests to create a Fuel ef ficiency fuel ef ficiency map ism, Japan. Figure 3-4 Japanese simulation method overview.eps HILS (3 small bitmapsewithop ctimulator) H ardware I n th L o ve Sor labels Chassis Base Vehicle Model D river model HEV ( Hybrid Electric Vehicle) Batter y model Hybrid ECU RESS Inverter imput Vehicle Motor Engine Parameters model model · Gear Ratio, ef f. Run JE05 · Eng. spec · Vehicle spec etc. 10 0 Virtual JE05 Running on CPU 80 Speed (kmh) 60 Get E / G rpm, E / G Torque 40 20 0 0 500 1000 1500 2000 Fuel Consumption Exhaust Emission Time (sec) Torque Engine E/ D Fuel Consumption Measurement of Ratio Exhaust Emission Engine speed FIGURE 3-5 Japanese hardware-in-the-loop Japanese hardware-in-loop simulation testing of h.eps Figure 3-5 simulation (HILS) testing of hybrid vehicles. SOURCE: Presentation to the committee by Akihiko Hoshi, Ministry of Land, Infrastructure, Transport, and Tourism, Japan. no technical validation (although in the case of tires, for OEMs currently offer at least one SmartWay trailer model, example, data proving low rolling resistance must be sup- and several manufacturers have developed aerodynamic plied for the designation). All six major U.S. truck manu- components that can be retrofitted. EPA has validated trailer facturers have one or more complying tractors. Manufacturer side skirts, trailer boat tails, and trailer gap reducers. compliance with the SmartWay specification is completely As an alternative to the aerodynamic specification for voluntary. the trailer, the EPA will grant certification upon review of SmartWay certification applies to 53-ft or longer dry demonstrated equivalent environmental performance for the box van trailers as well. To attain certification, these trailers aerodynamic specification, defined as 5 percent or greater fuel savings using an SAE J13212 test track procedure as must have side skirt fairings, a front gap or rear fairing, and SmartWay-approved low-rolling-resistance tires and can modified by EPA. have aluminum wheels. The fairings, tires, and wheels can be either provided by the original equipment manufacturer 2 SAE (Society of Automotive Engineers) J1321: Joint TMC/SAE Fuel (OEM) on new trailers or retrofitted to older trailers. Several Consumption Test Procedure–Type II. October 1986; update in progress.

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 REVIEW OF CURRENT REGULATORY APPROACHES FOR TRUCKS AND CARS FIGURE 3-6 EPA’s SmartWay logos. SOURCE: “External SmartWay Marks: SmartWay Tractors and Trailers,” available at http://www. epa.gov/otaq/smartway/transport/what-smartway/tractor-trailer-markuse.htm. Figure 3-6 EPA,s SmartWay Logos.eps 2 bitmaps FIGURE 3-7 Some of the aerodynamic technologies included in the SmartWay certification program. SOURCE: Mitch Greenberg, EPA, “SmartWay Voluntary Certification Program,” presentation to the committee. Figure 3-7 Some of the aerodynamic technologies included in.eps bitmap CALIFORNIA REGULATION BASED ON EPA gies, providing a phase-in period for larger fleets from 2010 SMARTWAY PROGRAM to 2015 and for smaller fleets from 2013 to 2016. One of the most significant consequences of the Smart- LIGHT-DUTY-VEHICLE FUEL ECONOMY STANDARDS Way certification program is action taken by the California Air Resources Board. With the intention to reduce the state’s The development of fuel consumption standards for pas- greenhouse gas emissions to 80 percent of 1990 levels by senger vehicles provides useful lessons for consideration 2020, in 2006 the California legislature approved the Global in trucks and buses. In 1975, Congress enacted the Energy Warming Solutions Act. A resulting action in December 2008 Policy and Conservation Act (EPCA, P.L. 94-163), with the was the adoption of a measure that defines a schedule by goal of reducing the nation’s dependence on foreign oil by a which all tractor-trailer combinations that operate in Califor- number of measures, including doubling the fuel economy nia will be required to implement SmartWay technologies. of passenger vehicles. The statute established a Corporate Beginning in January 2010, with the 2011 model year, all Average Fuel Economy (CAFE) program, which requires au- sleeper cab tractors that pull 53-ft or longer box van trailers tomobile manufacturers to increase the sales-weighted aver- must be SmartWay certified. Day cab tractors must have age fuel economy of their passenger car and light-truck fleets SmartWay-approved low-rolling-resistance tires. At the same sold in the United States. The metric chosen by Congress for time, in model year 2011 and beyond, all 53-ft or longer van expressing the standard was fuel economy expressed in miles trailers must also be SmartWay certified, based on either per gallon (mpg). OEM equipment or retrofits. The legislation also calls for retrofitting older trailers with SmartWay-approved technolo-

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 TECHNOLOGIES AND APPROACHES TO REDUCING THE FUEL CONSUMPTION OF MEDIUM- AND HEAVY-DUTY VEHICLES Measurement procedures in place in 1975 must continue to be used for calculating CAFE values. Passenger vehicle fuel economy is determined by testing In 2006, EPA reevaluated the difference between the test a vehicle on a chassis dynamometer. In the laboratory the results and the fuel economy experienced by the average vehicle’s drive wheels are placed on two 48-in.-diameter consumer. It found that the gap had widened since the early metal rollers—the dynamometer—that simulate the loads 1980s, in part because the underlying test procedures did experienced by the vehicle in the real world. The energy not fully represent real-world driving conditions. Thus, three required to move the rollers is adjusted to account for the additional tests have been added to the original city and high- vehicle’s weight and wind resistance and for the tire rolling way estimates to adjust for higher speeds, air-conditioning resistance of the two undriven wheels. The laboratory testing use, and colder temperatures. These tests, applied beginning is very repeatable and precise, allowing consistent results in 2008, were developed in two previous rulemakings for the across the vehicle fleet. purpose of controlling emissions under conditions not in- The levels of hydrocarbons (HCs), carbon monoxide cluded in the original FTP test. For the revised fuel economy (CO), carbon dioxide (CO2), and nitrous oxides (NOx) in labels, rather than basing the city mpg estimate solely on the the exhaust are measured using a constant-volume sampling adjusted FTP test result, and the highway mpg estimate sole- system. Fuel consumption is determined by summing all the ly on the adjusted highway fuel economy test (HFET) result, carbon in the exhaust and converting this to gallons using the each estimate will be based on a multiequation “composite” amount of carbon per gallon, although direct measurement calculation of all five tests, weighting each appropriately to of fuel consumed is greatly improved and is now routinely arrive at new city and highway mpg estimates. The new city used in parallel. and highway estimates will each be calculated according Manufacturers test their own vehicles and report the to separate city and highway “five-cycle” formulas based results to EPA. EPA reviews the results and confirms them on fuel economy results over these five tests. A simplified by testing 10 to 15 percent of the certified models at its own approach, called the mpg-based method, will be an interim laboratory. About 1,250 vehicle models are certified annually option in the first 3 years of the program and an available op- (EPA, 2006a). EPA is empowered to audit production-line tion under certain circumstances in subsequent years. It relies vehicles for compliance. For post-production vehicles in use, on data from the FTP and HFET cycles (EPA, 2006b). EPA conducts tests of vehicles from customers in real ser- Table 3-1 lists the key parameters of the five tests used to vice and gathers data from onboard diagnostics records and determine the fuel economy (of passenger vehicles) that is manufacturer in-use verification testing. EPA is empowered listed on the familiar window stickers. to require a recall of vehicles to correct defects in emission In summary, light-duty-vehicle emissions and fuel con- control systems. sumption regulations exemplify the compromises necessary due to the diversity of vehicle types and uses. One set of drive Test Cycles cycles is applied to about 1,200 vehicle models, over a wide range of weights, with the heaviest about twice the weight A test cycle is a series of driving routines that specify the of the lightest. Similarly, drive cycles cover a wide range vehicle speed for each second during a particular test. Two of powers, with the highest about five times as powerful as test cycles were originally used for determining compliance the lowest. Light-duty fuel economy regulations adopted with CAFE standards: (1) a city cycle originally developed in the same testing protocols used for emissions certification, the mid-1960s to represent home-to-work, urban commuting, and numerous adjustments and correction factors have been commonly referred to as the FTP (federal test procedure), needed to bring reported fuel economy values closer to con- and (2) a highway test cycle that represents a mix of rural sumer (real-world) experience. Concepts and recommenda- and interstate highway driving. tions for CAFE predated the regulation by 1 to 2 years, and The FTP was developed for emission control purposes, the regulation was not implemented until 1978. Hence, even not fuel economy, and the highway test reflects the 55-mph though there was the foundation of the emissions regula- speed limit that was in effect when the cycle was created. tions, the time, and presumably effort, needed to implement The EPA quickly realized that these factors caused the tests CAFE and its test protocols were very substantial (Greene to overstate the average in-use fuel economy. EPA spent and DeCicco, 2000). several years analyzing the average offset and in 1984 is- sued adjustments for the fuel economy label values that HEAVY-DUTY-ENGINE EMISSIONS REGULATIONS had been required on window stickers for all new cars since 1978. For the labels the city test results were discounted by Background, Test Methods, and Cycles 10 percent and the highway test results were discounted by 22 percent. However, the unadjusted values continued to be Pollutant emissions from heavy-duty vehicles are regu- used for CAFE purposes, as the EPCA specified that the test lated in terms of emissions from their engines. Faced with how to regulate emissions given the great diversity of heavy-

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 REVIEW OF CURRENT REGULATORY APPROACHES FOR TRUCKS AND CARS TABLE 3-1 Fuel Economy Vehicle Testing Original Test Cycles New Test Cycles Driving Schedule Air-Conditioning (AC) Attributes City Highway High Speed (US06) (SC03) Cold Temperature Trip type Low and moderate Free-flow traffic Higher speeds; harder AC use under hot ambient City test w/cold speeds in urban traffic at highway speeds acceleration and braking conditions and full sun load outside temperature Top speed 56 mph 60 mph 80 mph 54.8 mph 56 mph Average speed 21.2 mph 48.3 mph 48.4 mph 21.2 mph 21.2 mph Maximum acceleration 3.3 mph/sec 3.2 mph/sec 8.46 mph/sec 5.1 mph/sec 3.3 mph/sec Simulated distance 11 miles 10.3 miles 8 miles 3.6 miles 11 miles Time 31.2 min. 12.75 min. 9.9 min. 9.9 min. 31.2 min. Stops 23 None 4 5 23 Idling time 18% of time None 7% of time 19% of time 18% of time Engine startupa Cold Warm Warm Warm Cold 68°-86°F 95°F 20°F Lab temperature Vehicle air conditioning Off Off Off On Off aAvehicle’s engine does not reach maximum fuel efficiency until it is warm. SOURCE: Department of Energy. duty vehicles, EPA chose many years ago to regulate the sampling point downstream in the dilution tunnel and are engine manufacturers. A number of reasons can be cited: in integrated with respect to the flow to yield a total mass for many cases the engine and chassis are produced by differ- the cycle. A background correction is applied to remove the ent manufacturers; it is more efficient to hold a single entity mass of pollutant that may be in the dilution air. The net responsible; and testing an engine cell is more accurate and mass is divided by the energy out of the engine over the repeatable than testing a whole vehicle. About 275 engine cycle to yield brake-specific emissions. Particulate matter models are certified for heavy trucks each year, consider- (PM) is measured by filtering a slipstream of dilute exhaust, ably fewer than the number of passenger vehicles that are weighing the filter, and projecting the total PM mass from certified. the ratio of total flow to slipstream flow. Although NOx, CO, Emissions standards for heavy-duty engines are expressed and HCs are the regulated emissions, CO2 is also measured in in terms of mass (grams) per unit of energy output. Energy most test cells, and this measurement may be used to project output is expressed in horsepower-hours (hp-hr) or kilowatt- the engine brake-specific fuel consumption. Fuel mass or hours (kWh), so the standards are expressed as g/hp-hr or volume flow is also measured in many test cells, providing a g/kWh. The Code of Federal Regulations (40 CFR Part 86) separate check. During the testing, certain loads, such as wa- requires that the engine be connected to a dynamometer in a ter pump and oil pump demands, are met by the engine, but test cell and be exercised through a transient test procedure engine coolant heat exchange and intercooler heat removal (the FTP). The FTP was created from data logged from are supplied by the test cell. trucks and buses operating in Los Angeles and New York as The practice of testing and certifying only the engine part of the CAPE-21 Coordinating Research Council (CRC) (across selected cycles), and not the entire vehicle, was an program of 1973 to 1977 (CRC, 1973, 1974, 1977). Speed accepted compromise for pollutant emissions. Even with data were converted to percentage values with idle speed set this simplified engine-only approach, the FTP transient test at zero percent and rated speed set at 100 percent; torque data procedures were under development at EPA for 5 years, and were converted to a zero to 100 percent torque referenced to several years more were needed for the industry to employ zero torque and maximum engine torque at each speed. The electric dynamometers, constant-volume samplers, dilution FTP was created using a Monte Carlo simulation based on systems, and new measurement systems for PM (Merrion, percent speed and percent torque probabilities. The diesel 2002). engine procedure consists of a time sequence of rotational How representative of on-road emissions are the current speed and torque set points determined from a table of di- engine dynamometer procedures? John Wall presented an mensionless speeds and torques and a full-power map of the analysis to the committee comparing CO2 emissions from engine (Figure 3-8). Torque and speed regression criteria are the certification test process to over-the-road vehicle fuel consumption data.3 For line-haul truck duty cycles, CO2 available to determine whether the engine has been properly loaded during the test. A separate FTP schedule exists for emissions from vehicle field data were within 3.7 percent heavy-duty gasoline engines. of the CO2 emissions predicted from the Supplementary The whole engine exhaust is fed to a full-flow dilution tunnel and is mixed with dilution air to produce a constant- 3 John Wall, Cummins, Inc., presentation to the committee, August 6, volume flow. Gaseous concentrations are measured at a 2009.

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 TECHNOLOGIES AND APPROACHES TO REDUCING THE FUEL CONSUMPTION OF MEDIUM- AND HEAVY-DUTY VEHICLES 2500 2300 2100 1900 1700 Engine Speed (rpm) 1500 1300 1100 900 700 500 0 200 400 600 800 1000 1200 Time (s) 1500 1300 1100 90 0 Engine Torque ( f t- lbf) 70 0 50 0 30 0 10 0 -100 -300 -500 0 200 40 0 600 80 0 1000 1200 Time ( s) FIGURE 3-8 FTP speed (top) and torque (bottom) from a specific engine following the transient FTP on a dynamometer. SOURCE: Based on data from West Virginia Figure 3-8 FTP Speed (top) and torque (bottom) from a specif.eps University. Emission Test (SET) 13 mode engine data. For a set of field- on engine families that have similar displacements, number monitored vocational trucks, the FTP transient engine test of cylinders, fuel injection systems, turbocharging systems, data predicted CO2 emissions to within 4.0 percent of the on- and after-treatment systems. Several ratings of horsepower, road results. Further analysis would be needed to determine torque, and rpm can be included in one family. Emissions the breadth of vehicles and duty cycles that an engine-only testing then follows, conducted by the engine manufacturer. test could accurately cover, and this correlation would not This testing involves one “data engine” and a durability/dete- be expected to hold true for hybrid vehicles. rioration factor (DF) engine for each family. The data engine is run for 125 hours and emissions measured on the FTP and on the ramp modal cycle (RMC). The RMC replaced the SET Certification and Enforcement but is still a 13-mode steady-state test with emissions also The emissions certification process begins with a meeting measured during the ramp between modes. The DF engine with EPA to review the manufacturer’s product line and to is run for a period of time that is representative of 35 percent describe the emission control systems. Agreement is reached of the engine’s useful life, such as 1,000 hours at full load,

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 REVIEW OF CURRENT REGULATORY APPROACHES FOR TRUCKS AND CARS to demonstrate the durability of the emissions control sys- certification process focuses again on the engine only, tested tem and to establish the emissions deterioration. Emissions over prescribed cycles or steady-state modes. The engines are measured at three points during the DF test (125 hours, are divided into many classes depending on the size and type midpoint, and end of test) on the FTP and RMC. Following of use, and test cycles are prescribed for each class. testing, all data are submitted to EPA as part of the applica - tion for certification. REGULATORY EXAMPLE FROM TRUCK SAFETY BRAKE Following certification and production, an enforcement TEST AND EQUIPMENT process is in effect. EPA can come into the production facility and perform a Selective Enforcement Audit. It can sequester Heavy-duty vehicle regulations can be complex; how- 25 to 30 engines and start an audit process under which five ever, there are examples of compliance mechanisms that of these engines must be under the emission standards as provide flexibility and minimize the burden on industry. An measured on the FTP and RMC after a 125-hour condition- illustrative example is performance-based Federal Motor ing period. If failures occur, a statistical process is used that Vehicle Safety Standard (FMVSS) 121, which requires that may require all (25 to 30) engines to be tested. EPA can also a vehicle stop within a certain distance from an initial speed do in-use emissions testing on vehicles in regular service. when loaded to the GVW rating (Table 3-2). The stopping This testing is done using a Portable Emission Measurement distance is dependent on vehicle type. For example, from an System either over-the-road or on a chassis dynamometer. initial speed of 60 mph, truck tractors must stop within 355 Emissions are measured over a 30-minute period (constantly ft, single-unit trucks within 310 ft, and buses within 280 ft updating) and a determination is made as to whether emis- (NHTSA, 2004). This example illustrates clearly that regu- sions are exceeding the not-to-exceed values (usually either latory requirements can differ for the various vehicle types 125 or 150 percent of the regulated values depending on the within the general class of heavy-duty vehicles. engine family). The brake performance evaluation of trailers is carried out Compliance flexibility is provided with averaging, bank- differently than for trucks and buses in that, because they are ing, and trading, which can take place among engine families not self-powered, trailers have a dynamometer requirement or with other manufacturers. Also, a provision to pay non- rather than a test track requirement (NHTSA, 1990). This il- compliance penalties is available if the manufacturer wants lustrates that the test methods for a given heavy-duty vehicle to certify to an emissions level higher than the standard. regulation can vary significantly depending on the vehicle unit (e.g., truck-tractors or trailers). Because the heavy-duty truck market is so complex, and Chassis Testing for Certain Heavy Vehicle Classes many of the vehicles are custom-built (as discussed in Chap- A chassis cycle or schedule may be used for the emissions ter 2), regulations applied at the final stage of manufacture certification of certain Class 2B vehicles as an alternative to can pose a heavy burden on the manufacturer. However, this the heavy-duty engine dynamometer procedure. Historically, burden can be lessened by “type approval” at the component the Class 2B vehicle manufacturer was also the manufac- level. For example, in the case of brake regulations, truck turer of the engine, because Class 2B vehicles were gaso- axle manufactures supply brakes with the axle assemblies line powered and usually produced by a light-duty-vehicle properly sized and rated for the load that the axle is designed manufacturer. EPA Tier 2 light-duty emissions requirements to carry. By using these axles the final-stage manufacturer were extended to include medium-duty passenger vehicles, can assure compliance with the brake regulations without which are between 8,501 and 10,000 lb gross vehicle weight (GVW) and may include diesel-powered vehicles. The EPA’s TABLE 3-2 Stopping Distances Required by FMCSS 121 2006 regulatory announcement (EPA, 2006b) explains that Regulation larger sport utility vehicles and vans (8,501- to 10,000-lb GVW) will require light-duty-style fuel economy measure- Service Brake Stopping Distance (ft) ments from 2011. California’s Low Emission Vehicle (LEV Vehicle Loaded and Loaded Unloaded Truck Loaded II) regulations cover emissions from vehicles in the 8,501- to Speed Unloaded Single-Unit Tractors and Truck 14,000-lb range through chassis testing. A federal option also (mph) Buses Trucks Single-Unit Trucks Tractors exists for chassis testing of vehicles up to 14,000 lb GVW. 20 32 35 38 40 25 49 54 59 62 30 70 78 84 89 Nonroad Engines 35 96 106 114 121 40 125 138 149 158 EPA began regulation of nonroad engines in the mid- 45 158 175 189 200 1990s, with regulations now covering the immense range 50 195 216 233 247 from handheld spark ignition engines (such as leaf blowers) 55 236 261 281 299 to locomotive engines. Stated by EPA as being one of the 60 280 310 335 355 most complex sets of emissions regulations undertaken, the SOURCE: Adapted from NHTSA (2004).

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0 TECHNOLOGIES AND APPROACHES TO REDUCING THE FUEL CONSUMPTION OF MEDIUM- AND HEAVY-DUTY VEHICLES Finding 3-4. The legislation passed by California requiring having to test each vehicle. In effect the regulatory effort has cascaded down to the component manufacturer, provid- tractor-trailer combinations to be SmartWay certified will ing much-needed design flexibility to the final-stage manu- have a significant impact on the number of vehicles in the facturer (which would not have to test every vehicle design United States that are specified with fuel-efficient technolo- variation). Aspects of this regulatory model may prove useful gies beginning in 2010. in the development of regulatory instruments for governing heavy-duty truck fuel consumption. REFERENCES CRC (Coordinating Research Council). 1973. Heavy-Duty Vehicle Driving FINDINGS Pattern and Use Survey. Columbia, S.C.: Wilbur Smith and Associates. May. Finding 3-1. Regulators have dealt effectively with the CRC. 1974. Heavy-Duty Vehicle Driving Pattern and Use Survey: diversity and complexity of the vehicle industry for cur- Part II—Los Angeles Basin. Columbia, S.C.: Wilbur Smith and As- rent laws on fuel consumption and emissions for light-duty sociates. February. CRC. 1977. Truck Driving Pattern and Use Survey—Phase II. Columbia, vehicles. Engine-based certification procedures have been S.C.: Wilbur Smith and Associates. June. applied to address emissions from heavy-duty vehicles and EPA (U.S. Environmental Protection Agency). 2006a. Fuel Economy the myriad of nontransportation engines. Regulators and Labeling of Motor Vehicles: Revisions to Improve Calculation of industry have reached consensus in these cases, but years of Fuel Economy Estimates, Final technical support document. 40 CFR development of procedures and equipment for certification, Parts 86 and 600 [EPA-HQ-OAR-2005-0169; FRL-8257-5]. Federal Register: Dec. 27, 2006 (Vol. 71, No. 248): Rules and Regulations: compliance, and the defining the standards themselves have Pp. 77871-77969. been required. Standardized drive or operating cycles are EPA. 2006b. Regulatory Announcement: EPA Issues New Test Methods utilized in all emissions and fuel consumption regulations for Fuel Economy Window Stickers. EPA fact sheet, document number to represent actual use of the vehicle or engine. EPA420-F-06-069. Available at http://www.epa.gov/fueleconomy/ 420f06069.htm. Finding 3-2. The heavy-duty-truck fuel consumption regu- Greene, D., and J. DeCicco. 2000. Engineering and economic analyses of automotive fuel economy potential in the United States. Annual Reiew lations in Japan, and those under consideration and study of Energy and the Enironment. Vol. 25, pp. 477-535. November. by the European Commission (EC), provide valuable input Merrion, D. 2002. Heavy Duty Diesel Emissions, Fifty Years, 1960-2010. and experience to the U.S. plans. In Japan the complexity Proceedings of the 2002 Fall Technical Conference of the ASME Inter- of medium- and heavy-duty vehicle configurations and duty nal Combustion Engine Division, New Orleans, La., Sept. 8-11. New York: American Society of Mechanical Engineers. cycles was determined to lend itself to the use of computer Morita, K., K. Shimamura, S. Yamaguchi, K. Furumachi, N. Osaki, S. Na - simulation as a cost-effective means to calculate fuel effi- kamura, K. Narusawa, K-J. Myong, and T. Kawai. 2008. Development ciency. The EC studies thus far indicate plans to develop and of a fuel economy and exhaust emissions test method with HILS for use simulations in the expected European regulatory system. heavy-duty HEVs. SAE Paper 2008-01-1318. Also in SAE International Japan is not using extensive full-vehicle testing in the certi- Journal of Engines. NHTSA (National Highway Traffic Safety Administration, U.S. Depart- fication process, despite the fact that its heavy-duty-vehicle ment of Transportation). 1990. Laboratory Test Procedure for Federal manufacturing diversity is less than in the United States, Motor Vehicle Safety Standards and Regulations No. 121D, Air Brake with relatively few heavy-duty-vehicle manufacturers and Systems—Dynamometer, TP-121D-01. May. Available at http://www. no independent engine companies. nhtsa.dot.gov/cars/rules/import/fmvss/index.html#SN121. NHTSA. 2004. Laboratory Test Procedure for FMVSS, No. 121, Air Brake Finding 3-3. The existing regulations pertaining to me- Systems, TP-121V-05. March 12. Sato, S. 2007. Fuel Economy Test Procedure for Heavy Duty Vehicles, dium- and heavy-duty vehicle safety and emissions provide Japanese Test Procedures, Presented at the IEA/International Transport examples indicating that the industry’s diversity is ad- Forum Workshop on Standards and Other Policy Instruments on Fuel dressed by requiring compliance, or at least conformity, at Efficiency for HDVs, Paris France, June 21-22. the component level, reducing the regulatory burden on the final-stage manufacturer and thus preserving the flexibility of assembly to meet customer demands.