F

Proposed Mechanism for Obtaining Hybrid Vehicle Credits

The U.S. Environmental Protection Agency (EPA) and the U.S. Department of Transportation National Highway Traffic Safety Administration (DOT/NHTSA) issued proposed greenhouse gas emissions standards and fuel efficiency standards for medium- and heavy-duty engines in a notice of proposed rulemaking (NPRM) on October 26, 2010 (EPA/NHTSA, 2010a,b). On September 15, 2011, the EPA and NHTSA issued final greenhouse gas emissions standards and fuel efficiency standards for medium- and heavy-duty engines and vehicles that are tailored to each of three regulatory categories of heavy-duty vehicles: (1) Heavy-Duty Pickup Trucks and Vans, (2) Vocational Vehicles, and (3) Combination Tractors (EPA/NHTSA, 2011a). The agencies are providing credits for the use of hybrid powertrain technology as an incentive (EPA/NHTSA 2011a,b). The approach to account for the use of a hybrid powertrain when evaluating compliance with the standards is described below.

HEAVY-DUTY PICKUP AND VAN HYBRIDS

Test Procedure

For the heavy-duty pickup truck and van hybrid class of vehicles with gross vehicle weight ratings [GVWRs] between 8,500 and 14,000 lb (that are not already covered under the Model Year 2012-2016 light-duty truck and medium-duty passenger vehicle greenhouse gas [GHG] standards), the agencies have proposed that testing would be done using adjustments to the test procedures developed for light-duty hybrids, using the light-duty Federal Test Procedure (FTP) and the Highway Fuel Economy Test (HWFET), but extending the requirement for chassis certification for CO2 emissions to diesel-powered vehicles. Currently, chassis certification is a gasoline requirement and a diesel option. Manufacturers would be allowed to continue to certify engines for criteria pollutant (non-GHG) requirements as they do today.

Fuel-Consumption Credits

The EPA and NHTSA fuel-consumption standards are expressed on a gal/100 mile basis, and that would apply to a manufacturer’s fleet of heavy-duty pickup trucks and vans with a GVWR from 8,500 to 14,000 lb. The credits for the hybrid vehicle would be calculated according to the Averaging, Banking, and Trading (ABT) program described by an equation for fuel consumption credits given later in this section.

A manufacturer’s credit or debit balance will be determined by calculating its fleet average performance using the data from the FTP and HWFET tests and comparing this data to the manufacturer’s fuel-consumption standards, as determined by its fleet mix, for a given model year. A target standard is determined for each vehicle with a unique payload, towing capacity, and drive configuration (two-wheel versus four-wheel drive). These unique targets, weighted by their associated production volumes, are summed at the end of the model year to derive the production volume-weighted manufacturer annual fleet average standard. A manufacturer would generate credits if its fleet average fuel-consumption level were lower than its standard and would generate debits if its fleet average fuel-consumption level were above that standard.

In addition to production weighting, the credit calculations include a factor for the useful life, in miles, in order to allow the expression of credits in gallons. The following equation is used to calculate credits (debits) and account for the amount that the family limit is below (above) the standard, the payload tons, the sales volume, and the useful life.

Fuel Consumption Credits (gallons) = (FC Std - FC Act) × Volume × UL × 100,

where:

FC Std = Fleet average fuel-consumption standard (gal/100 mile)

FC Act = Fleet average actual fuel-consumption value (gal/100 mile)



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F Proposed Mechanism for Obtaining Hybrid Vehicle Credits Fuel-Consumption Credits The U.S. Environmental Protection Agency (EPA) and the U.S. Department of Transportation National Highway Traffic The EPA and NHTSA fuel-consumption standards are Safety Administration (DOT/NHTSA) issued proposed green- expressed on a gal/100 mile basis, and that would apply to a house gas emissions standards and fuel efficiency standards manufacturer’s fleet of heavy-duty pickup trucks and vans with for medium- and heavy-duty engines in a notice of proposed a GVWR from 8,500 to 14,000 lb. The credits for the hybrid rulemaking (NPRM) on October 26, 2010 (EPA/NHTSA, vehicle would be calculated according to the Averaging, Bank- 2010a,b). On September 15, 2011, the EPA and NHTSA ing, and Trading (ABT) program described by an equation for issued final greenhouse gas emissions standards and fuel fuel consumption credits given later in this section. efficiency standards for medium- and heavy-duty engines and A manufacturer’s credit or debit balance will be determined vehicles that are tailored to each of three regulatory categories by calculating its fleet average performance using the data of heavy-duty vehicles: (1) Heavy-Duty Pickup Trucks and from the FTP and HWFET tests and comparing this data to Vans, (2) Vocational Vehicles, and (3) Combination Tractors the manufacturer’s fuel-consumption standards, as determined (EPA/NHTSA, 2011a). The agencies are providing credits by its fleet mix, for a given model year. A target standard is for the use of hybrid powertrain technology as an incentive determined for each vehicle with a unique payload, towing (EPA/NHTSA 2011a,b). The approach to account for the use capacity, and drive configuration (two-wheel versus four- of a hybrid powertrain when evaluating compliance with the wheel drive). These unique targets, weighted by their associ- standards is described below. ated production volumes, are summed at the end of the model year to derive the production volume-weighted manufacturer annual fleet average standard. A manufacturer would generate HEAVY-DUTY PICKUP AND VAN HYBRIDS credits if its fleet average fuel-consumption level were lower than its standard and would generate debits if its fleet average Test Procedure fuel-consumption level were above that standard. In addition to production weighting, the credit calculations For the heavy-duty pickup truck and van hybrid class include a factor for the useful life, in miles, in order to allow of vehicles with gross vehicle weight ratings [GVWRs] the expression of credits in gallons. The following equation is between 8,500 and 14,000 lb (that are not already covered used to calculate credits (debits) and account for the amount u nder the Model Year 2012-2016 light-duty truck and that the family limit is below (above) the standard, the payload medium-duty passenger vehicle greenhouse gas [GHG] tons, the sales volume, and the useful life. standards), the agencies have proposed that testing would be done using adjustments to the test procedures developed for Fuel Consumption Credits (gallons) = (FC Std − FC Act) light-duty hybrids, using the light-duty Federal Test Proce- × Volume × UL × 100, dure (FTP) and the Highway Fuel Economy Test (HWFET), but extending the requirement for chassis certification for where: CO2 emissions to diesel-powered vehicles. Currently, chassis FC Std = Fleet average fuel-consumption standard certification is a gasoline requirement and a diesel option. (gal/100 mile) Manufacturers would be allowed to continue to certify FC Act = Fleet average actual fuel-consumption value engines for criteria pollutant (non-GHG) requirements as (gal/100 mile) they do today. 166

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167 APPENDIX F Volume = Total production of vehicles in the regulatory tion reductions that would be realized from their systems in category the real world. The composite PTO test cycle for utility and UL = Useful life for the regulatory category (miles) refuse trucks is described in greater detail in EPA/NHTSA (2011b, see Table 3-23). VOCATIONAL VEHICLE AND TRACTOR HYBRIDS Engine Dynamometer Evaluation Test Procedure The engine test procedure involves exercising the con- For vocational vehicles and combination tractors incorpo- ventional engine and the hybrid-engine system based on an rating hybrid powertrains, the agencies specify two methods engine testing strategy. Real-world functionality would need for establishing credits. The first method uses chassis dyna- to be accurately represented. The testing would also need to mometer evaluation of the vehicle, and the second method uses recover vehicle kinetic energy. The agencies specify the use engine dynamometer evaluation with the powerpack in either a of the Heavy-Duty Engine FTP cycle for evaluation of hybrid (1) pre-transmission format or a (2) post-transmission format. vehicles, which is the same test cycle specified for engines Each method requires a comparison test of the actual physi- used in vocational vehicles. Engine dynamometer evaluation cal product, because the agencies are not aware of analytical may be undertaken in one of two ways: models that can assess the technology. 1. Pre-transmission power-pack testing, which includes the engine and hybrid systems in a pre-transmission Chassis Dynamometer Evaluation format, could utilize existing engine certification duty cycles. Changes to how the engine certification would Similar to heavy-duty pickup and van hybrids, to generate be conducted to address energy capture and idle opera- credits for hybrid vocational vehicles, full vehicle chassis tion would need to be evaluated as a complete protocol dynamometer testing is a straightforward basis for compar- is developed. ing fuel consumption performance of hybrid vehicles to 2. Post-transmission power-pack testing, which includes conventional vehicles. The agencies specify two sets of the transmission, would require a vehicle-like duty duty cycles for vocational trucks to evaluate the benefit cycle, which provides the appropriate speeds and depending on the vehicle application. The key difference torques to match field operation. between the two sets is that one does not include operation of a power take-off (PTO) unit while the other does. For example, delivery trucks do not operate a PTO while bucket Fuel-Consumption Credits and refuse trucks do. The duty cycles that apply to hybrid powertrains without Heavy-duty hybrid vehicles and hybrid powertrains can a PTO system are shown in Table F-1. be certified using an A to B test method. This concept entails The transient cycle, derived from the California Air testing the conventional vehicle or powertrain, identified as R esources Board (CARB) Heavy-Duty Truck 5 Mode “A,” and the hybrid version of the vehicle or powertrain, Cycle, is 668 seconds long and travels 2.84 miles. The cycle identified as “B.” The benefit associated with the hybrid contains 5 stops and contains 112 seconds of idling. The system for fuel consumption would be determined from the maximum speed of the cycle is 47.5 mph with an average weighted fuel-consumption results from the tests of each speed of 15.3 mph. The High Speed and Low Speed Cruise vehicle or hybrid powertrain, as described below: modes reflect constant speed cycles at 65 mph and 55 mph, respectively, which are representative of drivers using cruise 1. Improvement Factor = (Fuel Cons_A − Fuel Cons_B)/ control whenever possible. The final rules include a new (Fuel Cons_A) optional PTO test cycle in addition to the standard set of test 2. Gallons/1,000 ton-mile benefit = Improvement Factor cycles in order for manufacturers of advanced PTO systems × GEM Fuel Cons Result_B to demonstrate in the laboratory environment fuel consump- Note in the above equations that the GEM (Greenhouse Gas Emissions Model) result would be calculated for the base vehicle or powertrain without hybridization, and the Improve- TABLE F-1 Proposed Drive-Cycle Weightings (percent) ment Factor would account for hybridization of the vehicle or for Hybrid Vehicles Without Power Take-off powertrain. Vehicle Category Transient 55 mph 65 mph The following equation for the credits (debits) accounts for the amount that the family emission limit is below (above) Vocational vehicle 75 9 16 Day cab tractor 19 17 64 the standard, the payload tons, the production volume, and Sleeper cab tractor 5 9 86 the useful life:

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168 REVIEW OF THE 21ST CENTURY TRUCK PARTNERSHIP, SECOND REPORT Fuel Consumption credit (deficit)(gallons) = (Std-FEL) × Early credits provide an incentive for manufacturers to intro- (Payload Tons) × (Volume) × (UL) × 103, duce more efficient engines and vehicles earlier than required by the standards. where: Std = Standard associated with the regulatory category Advanced Technology Credits ( gallons/1,000 ton-mile) (fuel consumption: Gal - lons/1,000 ton-mile) The final rules include a provision for obtaining credits for introducing advanced technologies to provide an incentive for Payload tons = Prescribed payload for each subcategory their introduction. A 1.5 multiplier will be applied to these cred- (12.5 tons for Class 7 tractors, 19 tons for Class 8 tractors, its, but the total credits are capped in any model year. Hybrid 2.85 tons for light heavy-duty [LHD] vocational, 5.6 tons powertrain designs that include energy storage systems are one for medium heavy-duty [MHD] vocational, 7.5 tons for of the advanced technologies defined by the agencies. heavy heavy-duty [HHD] vocational vehicles) REFERENCES FEL = Family emission or fuel-consumption limit for the EPA/NHTSA (Environmental Protection Agency [Office of Transporta- vehicle family (gallons/1,000 ton miles) tion and Air Quality]/National Highway Traffic Safety Administration [Department of Transportation]). 2010a. Greenhouse Gas Emissions Volume = (Projected or actual) production volume of the Standards and Fuel Efficiency Standards for Medium- and Heavy- vehicle family Duty Engines and Vehicles. Dockets No. EPA-HQ-OAR-2010-0162 and No. NHTSA-2010-0079, October 25, 2010. Available at http://www. regulations.gov. UL = Useful life of the vehicle (435,000 miles for HHD, EPA/NHTSA. 2010b. Draft Regulatory Impact Analysis, Proposed Rule- 185,000 miles for MHD, and 110,000 miles for LHD) making to Establish Greenhouse Gas Emissions Standards and Fuel Ef - ficiency Standards for Medium- and Heavy-Duty Engines and Vehicles. EPA-420-D-10-901. October. Early Credits EPA/NHTSA. 2011a. Greenhouse Gas Emissions Standards and Fuel Ef- ficiency Standards for Medium- and Heavy-Duty Engines and Vehicles, The final rules include an option for a manufacturer to Final Rules. August 9. obtain early credits by certifying a subcategory of vehicles EPA/NHTSA. 2011b. Final Rulemaking to Establish Greenhouse Gas at fuel-consumption levels below the standard prior to the Emissions Standards and Fuel Efficiency Standards for Medium- and model year the standard becomes effective. A 1.5 multiplier Heavy-Duty Engines and Vehicles, Regulatory Impact Analysis. EPA- will be applied to early credits earned in model year 2013. 420-R-11-901. August.