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The U.S. Environmental Protection Agency (EPA) contracted with FEV, Inc. to estimate the per-vehicle cost of employing selected advanced efficiency-improving technologies in light-duty motor vehicles. The development of transparent, reliable cost analyses that are accessible to all interested stakeholders has played a crucial role in establishing feasible and cost effective standards to improve fuel economy and reduce greenhouse gas (GHG) emissions. The FEV team, together with engineering staff from EPA's National Vehicle and Fuel Emissions Laboratory, and FEV's subcontractor, Munro & Associates, developed a robust costing methodology based on tearing down, to the piece part level, relevant systems, sub-systems, and assemblies from vehicles ?with and without? the technologies being evaluated.

As part of the midterm evaluation of the 2022-2025 Light-Duty Vehicle Greenhouse Gas (GHG) Standards, the U.S. Environmental Protection Agency (EPA) developed simulation models for studying the effectiveness of 48V mild hybrid electric vehicle (MHEV) technology for reducing CO2 emissions from light-duty vehicles. Simulation and modeling of this technology requires a suitable model of the battery. This article presents the development and validation of a 48V lithium-ion battery model that will be integrated into EPA’s Advanced Light-Duty Powertrain and Hybrid Analysis (ALPHA) vehicle simulation model and that can also be used within Gamma Technologies, LLC (Westmont, IL) GT-DRIVE™ vehicle simulations. The battery model is a standard equivalent circuit model with the two-time constant resistance-capacitance (RC) blocks.

Emissions from manual transmission motorcycles have been shown to be dependent upon transmission shift patterns. Presently, when undergoing an emission test for an Environmental Protection Agency (EPA) certification a manufacturer can designate their own shift points during the cycle or utilize an EPA prescribed shift pattern which uses basic up or down shifts at specific speeds regardless of the type of motorcycle, 40 CFR 86.528-78(h). In order to predict the real-life emissions from motorcycles, a comparative real-life shift pattern has been developed which can then be used to evaluate the suitability of the manufacturer’s shift schedule. To that end, a model that predicts shift points for motorcycles has been created. This model is based on the actual operation of different motorcycles by real life operators in a combined city and highway setting.

The U.S. Environmental Protection Agency (EPA) contracted with FEV, Inc. to estimate the per-vehicle cost of employing selected advanced efficiency-improving technologies in light-duty motor vehicles. The development of transparent, reliable cost analyses that are accessible to all interested stakeholders has played a crucial role in establishing feasible and cost effective standards to improve fuel economy and reduce greenhouse gas (GHG) emissions. The FEV team, together with engineering staff from EPA's National Vehicle and Fuel Emissions Laboratory, and FEV's subcontractor, Munro & Associates, developed a robust costing methodology based on tearing down, to the piece part level, relevant systems, sub-systems, and assemblies from vehicles “with and without” the technologies being evaluated.

There has been considerable interest in applying remote measuring methods to sample in-use vehicle emissions, and to characterize fleet emission behavior. A Remote Sensing Device (RSD) was used to measure on-road carbon monoxide (CO) emissions from approximately 350 in-use vehicles that had undergone transient mass emission testing at a centralized I/M lane. On-road hydrocarbon (HC) emissions were also measured by the RSD on about 50 of these vehicles. Analysis of the data indicates that the RSD identified a comparable number of the high CO emitters as the two speed I/M test only when an RSD cutpoint much more stringent than current practice was used. Both RSD and I/M had significant errors of omission in identifying High CO Emitters based on the mass emission test. The test data were also used to study the ability of the RSD to characterize fleet CO emissions.

This report describes in detail new test procedures designed to minimize test variability, and the resulting false failures of new technology vehicles. There are currently six promulgated test procedures. The new procedures differ from the current ones in that they include controlled preconditioning, second chance testing, and sampling and score selecting algorithms. These are intended to minimize the variability in testing conditions and thereby reduce false failures of clean vehicles. High emitting vehicles which have been escaping detection with the current test procedures may continue to do so under the new ones. It is EPA's hope that these new procedures will improve the possibility of using more stringent cutpoints and non-idle test modes in the future to detect these high emitters by eliminating the additional false failures that would otherwise occur by instituting such measures under current procedures.

The attractiveness of the hydraulic hybrid concept stems from the high power density and efficiency of the pump/motors and the accumulator. This is particularly advantageous in applications to heavy vehicles, as high mass translates into high rates of energy flows through the system. Using dry case hydraulic pumps further improves the energy conversion in the system, as they have 1-4% better efficiency than traditional wet-case pumps. However, evacuation of fluid from the case introduces air bubbles and it becomes imperative to address the deaeration problems. This research develops a bubble elimination efficiency testing apparatus (BEETA) to establish quantitative results characterizing bubble removal from hydraulic fluid in a cyclone deaeration device. The BEETA system mixes the oil and air according to predetermined ratio, passes the mixture through a cyclone deaeration device, and then measures the concentration of air in the exiting fluid.

Plug-in hybrid electric vehicles (PHEVs) have the ability to significantly reduce petroleum consumption. Argonne National Laboratory (Argonne), working with the FreedomCAR and Fuels Partnership, helped define the battery requirements for PHEVs. Previous studies demonstrated the impact of the vehicle's characteristics, such as its class, mass, or electrical accessories, on the requirements. However, questions on the impact of drive cycles remain outstanding. In this paper, we evaluate the consequences of sizing the electrical machine and the battery to follow standard drive cycles, such as the urban dynamometer driving schedule (UDDS), as well as real-world drive cycles in electric vehicle (EV) mode. The requirements are defined for several driving conditions (e.g., urban, highway) and types of driving behavior (e.g., smooth, aggressive).

The Advanced Light-Duty Powertrain and Hybrid Analysis tool (ALPHA) was created by EPA to evaluate the Greenhouse Gas (GHG) emissions of Light-Duty (LD) vehicles. ALPHA is a physics-based, forward-looking, full vehicle computer simulator capable of analyzing various vehicle types combined with different powertrain technologies. The ALPHA desktop application was developed using MATLAB/Simulink. The ALPHA tool was used to evaluate technology effectiveness and off-cycle technologies such as air-conditioning, electrical load reduction technology and road load reduction technologies of conventional, non-hybrid vehicles for the Midterm Evaluation of the 2017-2025 LD GHG rule by the U.S. Environmental Protection Agency (EPA) Office of Transportation and Air Quality (OTAQ).

EPA new-model fuel economy figures are presented for passenger vehicles and light duty trucks (those with GVW ratings up to 8500 lbs). The 1981 models are emphasized, with some comparisons to prior years included. Reader familiarity with the EPA tests, data bases, and analytical methods is assumed. Principal two-way analyses include comparisons of domestic vs. import, gasoline vs. Diesel, and Federal (49-state) vs. California vehicles. Sales fractions for a number of vehicle and engine emission control design features are included. The principal finding is that increased use of newer vehicle and emission control technologies in 1981 has accompanied significant fuel economy gains in spite of the tougher 1981 emission standards.

This is a summary compilation and analysis of exhaust-emission results and operating parameters from forty-five heavy-duty gasoline and diesel-powered vehicles tested over a 7.24-mile road course known as the San Antonio Road Route (SARR); and, for correlative purposes, on a chassis dynamometer.(2) Exhaust samples were collected and analyzed using the Constant Volume Sampler (CVS) technique similar to that used in emission testing of light-duty vehicles. On the road course, all equipment and instrumentation were located on the vehicle while electrical power was supplied by a trailer-mounted generator. In addition to exhaust emissions, operating parameters such as vehicle speed, engine speed, manifold vacuum, and transmission gear were simultaneously measured and recorded on magnetic tape. The forty-five vehicles tested represent various model years, GVW ratings, and engine types and sizes.

EPA Fuel economy figures are presented for model year 1982 cars and light duty trucks. Comparisons with the MPG figures of prior years are included. Sales penetrations of various vehicle, engine, and emission control design features are given, and domestic cars' MPG characteristics are compared to that of imports', gasoline vehicle MPG is compared to Diesel MPG, and 49-states MPG is compared to California MPG. Usage of newer vehicle technologies is continuing to increase, leading to continued growth in fuel economy capability in spite of stringent emission standards.

This the twelfth in a series of Papers on trends in EPA fuel economy, concentrates as usual on the current Model Year (1984). Final Corporate Average Fuel Economy (CAFE) production volumes and MPG figures have been used to update the data bases through the 1982 Model Year. This paper is different from earlier papers in four ways: 1) manufacturer-supplied production forecasts have been adjusted for both model years 1983 and 1984. 2) sales weighted MPG values at the nameplate level of aggregation are presented. 3) much of the analysis is stratified at the Domestic/European/Japanese manufacturer level, and 4) fuel economy analysis for Light Duty Trucks is not included. Conclusions are presented on the trends in fuel economy of the fleet as a whole and for various classes of vehicles.

The increased interest in use of methanol makes it important to determine what levels of methanol and formaldehyde emissions may be acceptable. This paper reviews the available health data for methanol and formaldehyde to define what approximate ranges of concentrations, termed ranges of concern, could be acceptable from a toxicological viewpoint. Air quality models are then used to predict the in-use fleet average exhaust emission levels in localized situations (heavily impacted by mobile sources) corresponding to these ranges of concern. Using predicted fleet compositions, approximate target emission levels are given for the light-duty portion of the fleet which could yield these fleet averages. Finally, there is a brief summary of available methanol and formaldehyde emissions data from neat methanol-fueled vehicles which are compared to the target levels.

This, the thirteenth in a series of papers on trends in EPA fuel economy, covers both passenger cars and light trucks and concentrates on the current model year, 1985. It differs from previous papers in two ways: 1) Model years 1975, 1980 and 1985 are highlighted, with the model years in between these rarely discussed; 2) The progress of the industry, as a whole, in improving fuel economy since 1975 is emphasized, and individual manufacturer data are de-emphasized. Conclusions are presented on the trends in fuel economy of the car and light truck fleets; the Domestic, European and Japanese market sectors; and various vehicle classes.

This, the fourteenth in this series of papers, examines trends in fuel economy, technology usage and estimated 0 to 60 MPH acceleration time for model year 1986 passenger cars. Comparisons with previous year's data are made for the fleet as a whole and using three measures of vehicle/engine size: number of cylinders, EPA car class, and inertia weight class. Emphasis on vehicle performance and fuel metering has been expanded and analysis of individual manufacturers has been deemphasized; comparisons of the Domestic, European, and Japanese market sectors are given increased emphasis.

The United States Environmental Protection Agency (EPA) has initiated Phase I of a regulatory program to control exhaust emissions of nonroad diesel engines over 37 kW. Central to any emissions regulation is the test procedure, which must include an appropriate test cycle. Based on actual in-use speed and estimated torque data collected from an agricultural tractor, a backhoe-loader, and a crawler tractor, three duty cycles were developed. Using an iterative process, comparison of chi-square statistical data was used to identify representative microtrips, segments of engine operation gathered during performance of selected activities. Representative microtrips for specific activities for a particular nonroad application were “strung” together to make up a test cycle. Before accepting the test cycle, data for the cycle was compared to statistical data used to characterize the raw data in an effort to validate that the cycle was representative of the raw data.

As part of the U.S. Environmental Protection Agency’s (EPA’s) continuing assessment of advanced light-duty automotive technologies in support of regulatory and compliance programs, a development project was started to study various test methods to benchmark Electric Drive Units (EDUs) consisting of an electric motor, inverter and a speed-reduction gearset. Several test methods were identified for consideration, including both in-vehicle testing of the complete EDU and stand-alone testing of the EDU and its subcomponents after removal from the vehicle. In all test methods explored, sweeps of speed and torque test points were conducted while collecting key EDU data required to determine efficiency, including motor torque and speed, direct current (DC) battery voltage and current into the inverter, and three-phase alternating current (AC) phase voltages and currents out of the inverter and into the electric motor.