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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.

Beginning in 2007, heavy-duty engine manufacturers in the U.S. have been responsible for verifying the compliance on in-use vehicles with Not-to-Exceed (NTE) standards under the Heavy-Duty In-Use Testing Program (HDIUT). This in-use testing is conducted using Portable Emission Measurement Systems (PEMS) which are installed on the vehicles to measure emissions during real-world operation. A key component of the HDIUT program is the generation of measurement allowances which account for the relative accuracy of PEMS as compared to more conventional, laboratory based measurement techniques. A program to determine these measurement allowances for gaseous emissions was jointly funded by the U.S. Environmental Protection Agency (EPA), the California Air Resources Board (CARB), and various member companies of the Engine Manufacturer's Association (EMA).

Current U.S. Army ground vehicles predominately use commercial off-the-shelf or modified commercial diesel engines as the prime mover. Unique military engines are typically utilized when commercial products do not meet the mobility requirements of the particular ground vehicle in question. In either case, such engines traditionally have been calibrated using North American diesel fuel (DF-2) and Jet Propellant 8 (JP-8) compatibility wasn't given much consideration since any associated power loss due to the lower volumetric energy density was not an issue for most applications at then targeted climatic conditions. Furthermore, since the genesis of the ‘one fuel forward policy’ of using JP-8 as the single battlefield fuel there has been limited experience to truly assess fuel effects on diesel engine combustion systems until this decade.

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.

On-vehicle proof-of-concept testing was conducted to evaluate the ability of the dual oxygen sensor catalyst evaluation method to identify serious losses in catalyst efficiency under actual vehicle operating conditions. The dual oxygen sensor method, which utilizes a comparison between an upstream oxygen sensor and an oxygen sensor placed downstream of the catalyst, was initially studied by the Environmental Protection Agency (EPA) under steady-state operating conditions on an engine dynamometer and reported in Clemmens, et al. (1).* At the time that study was released, questions were raised as to whether the technological concepts developed on a test fixture could be transferred to a vehicle operating under normal transient conditions.

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.

Current SAE practices for evaluating potential improvements in fuel economy on heavy-duty vehicles rely on gravimetric measurements of fuel tanks. However, the recent evolution of portable emissions measurement systems (PEMS) offers an alternative means of evaluating real-world fuel economy that may be faster and more cost effective. This paper provides a direct comparison of these two methods based on a recent EPA study conducted at Southwest Research Institute. More than 228 on-road tests were performed on two pairs of class 8 tractor-trailers according to SAE test procedure J1321 in an assessment of various chassis components designed to reduce drag losses on the vehicle. During these tests, SEMTECH-D™ portable emissions measurement systems from Sensor's, Incorporated were operating in each of the vehicles to evaluate emissions and to provide a redundant measure of fuel economy.

As part of the U.S. Environmental Protection Agency’s (EPA’s) continuing assessment of advanced light-duty (LD) automotive technologies to support the setting of appropriate national greenhouse gas (GHG) standards and to evaluate the impact of new technologies on in-use emissions, a 2016 Honda Civic with a 4-cylinder 1.5-liter L15B7 turbocharged engine and continuously variable transmission (CVT) was benchmarked. The test method involved installing the engine and its CVT in an engine-dynamometer test cell with the engine wiring harness tethered to its vehicle parked outside the test cell. Engine and transmission torque, fuel flow, key engine temperatures and pressures, and onboard diagnostics (OBD)/Controller Area Network (CAN) bus data were recorded.

This paper describes a method used to compare the emissions from transient operation of an engine with the emissions from steady state operating modes of the engine. Weightings were assigned to each mode based on the transient cycle under evaluation. The method of assigning the weightings for each mode took into account several factors, including the distance between each second of the transient cycle's speed-and-torque point requests (in a speed vs. torque coordinate system) and the given mode. Two transient cycles were chosen. The transient cycles were taken from actual in-use data collected on nonroad engines during in-field operation. The steady state modes selected were based on both International Standard Organization (ISO) test modes, as well as, augmentation based on contour plots of the emissions from nonroad diesel engines. Twenty-four (24) steady-state modes were used. The transient cycle's speed-and-torque points are used to weight each steady state mode in the method.

Recreational marine engine operation effects water quality as well as air quality. Significant quantities of hydrocarbons are discharged into the rivers, lakes, and estuaries used as recreational boating waters. In order to investigate the impact of recreational marine engine operation on water quality, a MerCruiser 3.0LX four-cylinder four-stroke inboard engine and a Mercury 650 two-cylinder two-stroke outboard engine were tested using EPA required certification procedures. Both engines were tested with exhaust gas/cooling water mixing (scrubbing) in the exhaust stream using both freshwater and saltwater. Additionally, the inboard engine was tested without exhaust scrubbing. Gaseous emissions (HC, NOX, CO, and CO2) from the engines were continuously measured using a constant volume sampling system. Both exhaust gas and cooling water samples were collected and speciated for hydrocarbon species present.

Six heavy-duty diesel engines were tested for exhaust emissions on the ISO 8-mode nonroad steady-state duty cycle and the U.S. FTP highway transient test cycle. Two of these engines were baseline nonroad engines, two were Tier 1 nonroad engines, and two were highway engines. One of the Tier 1 nonroad engines and both of the highway engines were also tested on three transient cycles developed for nonroad engines. In addition, published data were collected from an additional twenty diesel engines that were tested on the 8-mode as well as at least one transient test cycle. Data showed that HC and PM emissions from diesel engines are very sensitive to transient operation while NOx emissions are much less so. Although one of the nonroad transient duty cycles showed lower PM than the steady-state duty cycles, all four of the other cycles showed much higher PM emissions than the steady-state cycle.

In 2005, the United States Environmental Protection Agency (EPA) and Southwest Research Institute (SwRI) embarked on a mission to help the city of Beijing, China, clean its air. Working with the Beijing Environmental Protection Bureau (BEPB), the effort was a pilot diesel retrofit demonstration program involving three basic retrofit technologies to reduce particulate matter (PM). The three basic technologies were the diesel oxidation catalyst (DOC), the flowthrough diesel particulate filter (FT-DPF), and the wallflow diesel particulate filter (WF-DPF). The specific retrofit systems selected for the project were verified through the California Air Resources Board (CARB) or the EPA verification protocol [1]. These technologies are generally verified for PM reductions of 20-40 percent for DOCs, 40-50 percent for the FT-DPF, and 85 percent or more for the high efficiency WF-DPF.

The project objective was to investigate the ultrafine solid particle emissions of the prevalent traffic, by performing field measurements at an urban traffic artery in Zurich/Switzerland. Subsequently, various scenarios were postulated to assess the potential of the diesel particle filters (DPF) to improve curbside air quality. Soot aerosols are known to be carcinogenic [1]. If all heavy-duty diesel vehicles were equipped with DPFs, then the number of particles emitted from the entire vehicle fleet could be reduced by 75 to 80%. For PM10, the curtailment scope is considerably lower, around 20%, because more than half of those emissions are not from the exhaust and therefore would not be filtered.

Adding oxygenates to diesel fuel has shown the potential for reducing particulate (PM) emissions in the exhaust. The objective of this study was to select the most promising oxygenate compounds as blending components in diesel fuel for advanced engine testing. A fuel matrix was designed to consider the effect of molecular structure and boiling point on the ability of oxygenates to reduce engine-out exhaust emissions from a modern diesel engine. Nine test fuels including a low-sulfur (∼1 ppm), low-aromatic hydrocracked base fuel and 8 oxygenate-base fuel blends were utilized. All oxygenated fuels were formulated to contain 7% wt. of oxygen. A DaimlerChrysler OM611 CIDI engine for light-duty vehicles was controlled with a SwRI Rapid Prototyping Electronic Control System. The base fuel was evaluated in four speed-load modes and oxygenated blends only in one mode. Each operating mode and fuel combination was run in triplicate.

An oxidation catalyst was fitted on a DI diesel engine for an experimental study involving an oxidation catalyst and the use of superheated steam for fumigating the intake air. Results are compared with that of the influence of low level of fumigation of the intake air with superheated diesel fuel. Exhaust emissions of NOx, CO, UHC, TPM, SOF and Carbon were measured and quantified on upstream and downstream of a low light off temperature (250 °C) oxidation catalyst. The technique used an electric vaporizer for producing superheated steam and prevaporised superheated diesel fumes at 350 °C, respectively. A low emissions version of Perkins 4-236 engine with squish lip piston was run both with and without fumigation at two speeds 1200 rpm and 2200 rpm. Roughly covering both city and highway running conditions.

Results showed the influence of the oxidation catalyst on exhaust emissions from a DI diesel engine due to the partial premixing, fumigation of the intake air with diesel fuel. Exhaust emissions of NOx, CO, UHC, TPM, SOF and Carbon were measured and quantified on upstream and downstream of a low light off temperature (250 °C) oxidation catalyst. Two methods of diesel fumigation of the intake air with fuel were used. The difference between these two methods was the degree of premixing of diesel fuel with the intake air. The first technique used a high-pressure fine diesel spray onto a glow plug and the second technique used an electric vaporizer for prevaporised superheated diesel fumes at 350 °C. A low emissions version of Perkins 4-236 engine with squish lip piston was run both with and without fumigation at two speeds 1200 rpm and 2200 rpm. Roughly covering both city and highway running conditions.

The use of a partial flow sampling system (PFSS) to measure nonroad steady-state diesel engine particulate matter (PM) emissions is a technique for certification approved by a number of regulatory agencies around the world including the US EPA. Recently, there have been proposals to change future nonroad tests to include testing over a nonroad transient cycle. PFSS units that can quantify PM over the transient cycle have also been discussed. The full flow constant volume sampling (CVS) technique has been the standard method for collecting PM under transient engine operation. It is expensive and requires large facilities as compared to a typical PFSS. Despite the need for a cheaper alternative to the CVS, there has been a concern regarding how well the PM measured using a PFSS compared to that measured by the CVS. In this study, three PFSS units, including AVL SPC, Horiba MDLT, and Sierra BG-2 were investigated in parallel with a full flow CVS.

Remote sensing nitric oxide (NO) measurements are difficult to analyze because load varies among on-road vehicles measured by remote sensing and NO emissions are dependent on load. Remote sensing NO measurements were made on passenger cars in 1997, 1998, and 1999 in Chicago, IL at a site where few vehicles had loads greater than those encountered in the FTP. Passenger car NO emissions could be modeled by an equation with an age term and a load term for measurements made under moderate load. Onset of decreasing NO emissions with increasing load was observed to occur at lower load for older technology vehicles. Light duty vehicles were measured by remote sensing at two sites on the same ramp in Phoenix, AZ. A large proportion of the vehicles at one of the sites was under loads far in excess of those experienced in the FTP. NO could not be characterized by a single valued function of age and load for both Phoenix sites even though the fleet at the two sites was very similar.