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A prototype 2007 ISL Cummins diesel engine equipped with a diesel oxidation catalyst (DOC), diesel particle filter (DPF), variable geometry turbocharger (VGT), and cooled exhaust gas recirculation (EGR) was tested at Southwest Research Institute (SwRI) under a high-load accelerated durability cycle for 1000 hours with B20 soy-based biodiesel blends and ultra-low sulfur diesel (ULSD) fuel to determine the impact of B20 on engine durability, performance, emissions, and fuel consumption. At the completion of the 1000-hour test, a thorough engine teardown evaluation of the overhead, power transfer, cylinder, cooling, lube, air handling, gaskets, aftertreatment, and fuel system parts was performed. The engine operated successfully with no biodiesel-related failures. Results indicate that engine performance was essentially the same when tested at 125 and 1000 hours of accumulated durability operation.

A 2001 General Motors 4.3 liter V-6 marine engine was baseline emissions tested and then equipped with catalysts. Emission reduction effects of exhaust gas recirculation (EGR) were also explored. Because of a U.S. Coast Guard requirement that inboard engine surface temperatures be kept below 200°F, the engine's exhaust system, including the catalysts, was water-cooled. Engine emissions were measured using the ISO-8178-E4 5-mode steady-state test for recreational marine engines. In baseline configuration, the engine produced 16.6 g HC+NOx/kW-hr, and 111 g CO/kW-hr. In closed-loop control with catalysts, HC+NOx emissions were reduced by 75 percent to 4.1 g/kW-hr, and CO emissions were reduced by 36 percent to 70 g/kW-hr of CO. The catalyzed engine was then installed in a Sea Ray 190 boat, and tested for water reversion on both fresh and salt water using National Marine Manufacturers Association procedures.

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.

The goal of the automated mobility platforms (AMPs) initiative is to raise the bar of service regarding equity and sustainability for public mobility systems that are crucial to large facilities, and doing so using electrified, energy efficient technology. Using airports as an example, the rapid growth in air travel demand has led to facility expansions and congested terminals, which directly impacts equity (e.g., increased challenges for Passengers with Reduced Mobility [PRMs]) and sustainability—both of which are important metrics often overlooked during the engineering design process.

A simple, inexpensive, critical flow blender has been developed for filling a tedlar bag with controllable concentrations of HC, NOx, CO2, and CO gases at levels encountered in automobile emissions testing. According to a daily schedule, a technician takes the bag to all analyzer sites in the laboratory for analysis. The concentrations indicated by each site are compared to the overall averages. The results are stored in a computerized data base from which control charts, statistical analyses, and interpretations of significant differences among test sites can be made. The precision, accuracy, and statistical interpretations of the data are discussed.

Studies of emissions from vehicles equipped with catalysts have shown that some unregulated emissions can increase when a catalyst is used. One example of this is sulfuric acid, which has been studied extensively. Other unregulated emissions include ammonia and hydrogen cyanide. In a number of studies, these unregulated pollutant emissions have been measured from light-duty vehicles and heavy-duty engines. These emission levels were used in air quality dispersion models to predict the resultant air quality levels. The ambient concentrations predicted for each pollutant were then compared to suggested concentrations at which adverse health effects may be found to determine if additional monitoring or control would be indicated for these pollutants. It was determined that mobile source emissions of sulfuric acid, hydrogen cyanide, and ammonia do not in general result in ambient levels of concern for the air quality situations studied.

Battery electric vehicles (BEVs) offer the potential to reduce both oil imports and greenhouse gas emissions, but high upfront costs, battery-limited vehicle range, and concern over high battery replacement costs may discourage potential buyers. A subscription model in which a service provider owns the battery and supplies access to battery swapping infrastructure could reduce upfront and battery replacement costs with a predictable monthly fee, while expanding BEV range. Assessing the costs and benefits of such a proposal are complicated by many factors, including customer drive patterns, the amount of required infrastructure, battery life, etc. The National Renewable Energy Laboratory has applied its Battery Ownership Model to compare the economics and utility of BEV battery swapping service plan options to more traditional direct ownership options.

The Automotive Deployment Options Projection Tool (ADOPT) is a light-duty vehicle consumer choice and stock model supported by the U.S. Department of Energy's Vehicle Technologies Office. It estimates technology improvement impacts on future U.S. light-duty vehicles sales, petroleum use, and greenhouse gas emissions. ADOPT uses techniques from the multinomial logit method and the mixed logit method to estimate vehicle sales. Specifically, it estimate sales based on the weighted value of key attributes including vehicle price, fuel cost, acceleration, range and usable volume. The average importance of several attributes changes nonlinearly across its range and changes with income. For several attributes, a distribution of importance around the average value is used to represent consumer heterogeneity. The majority of existing vehicle makes, models, and trims are included to fully represent the market. The Corporate Average Fuel Economy regulations are enforced.

Hybrid electric vehicles, plug-in hybrid electric vehicles, and battery electric vehicles offer the potential to reduce both oil imports and greenhouse gases, as well as to offer a financial benefit to the driver. However, assessing these potential benefits is complicated by several factors, including the driving habits of the operator. We focus on driver aggression, i.e., the level of acceleration and velocity characteristic of travel, to (1) assess its variation within large, real-world drive datasets, (2) quantify its effect on both vehicle efficiency and economics for multiple vehicle types, (3) compare these results to those of standard drive cycles commonly used in the industry, and (4) create a representative drive cycle for future analyses where standard drive cycles are lacking.

A 2002 Cummins ISM engine was modified to be optimized for operation on gas-to-liquid (GTL) fuel and advanced emission control devices. The engine modifications included increased exhaust gas recirculation (EGR), decreased compression ratio, and reshaped piston and bowl configuration. The emission control devices included a deNOx filter and a diesel particle filter. Over the transient test, the emissions met the 2007 standards. In July 2004, the modified engine was installed into a Class 8 tractor for use by a grocery fleet. Chassis emission testing of the modified vehicle was conducted at the National Renewable Energy Laboratory's (NREL) Renewable Fuels and Lubricants (ReFUEL) facility. Testing included hot and cold replicate Urban Dynamometer Driving Schedule (UDDS) and New York Composite (NYComp) cycles and several steady-state points. The objective of the testing was to demonstrate the vehicle's with the modified engine.

Increasing fuel costs and the desire for reduced dependence on foreign oil has brought the diesel engine to the forefront of future medium-duty vehicle applications in the United States due to its higher thermal efficiency and superior durability. The main obstacle to the increased use of diesel engines in this platform is the upcoming extremely stringent, Tier 2 emission standard. In order to succeed, diesel vehicles must comply with emissions standards while maintaining their excellent fuel economy. The availability of technologies such as common rail fuel injection systems, low sulfur diesel fuel, NOX adsorber catalysts (NAC), and diesel particle filters (DPFs) allow the development of powertrain systems that have the potential to comply with these future requirements. In meeting the Tier 2 emissions standards, the heavy light-duty trucks (HLDTs) and medium-duty passenger vehicles (MDPVs) will face the greatest technological challenges. In support of this, the U.S.

Increasing fuel costs and the desire for reduced dependence on foreign oil has brought the diesel engine to the forefront of future medium-duty vehicle applications in the United States due to its higher thermal efficiency and superior durability. The main obstacle to the increased use of diesel engines in this platform is the upcoming extremely stringent, Tier 2 emission standard. In order to succeed, diesel vehicles must comply with emissions standards while maintaining their excellent fuel economy. The availability of technologies such as common rail fuel injection systems, low sulfur diesel fuel, NOX adsorber catalysts (NAC), and diesel particle filters (DPFs) allow the development of powertrain systems that have the potential to comply with these future requirements. In meeting the Tier 2 emissions standards, the heavy light-duty trucks (HLDTs) and medium-duty passenger vehicles (MDPVs) will face the greatest technological challenges. In support of this, the U.S.

Fleet managers need a tool to assist them in assessing their need to comply with EPAct and to provide them with the ability to obtain information that will allow them to make alternative fuel vehicle purchasing decisions. This paper will describe the Web-based tool that will inform a fleet manager, based on their geographic location, the type of fleet they own or operate, and the number and types of vehicles in their fleet, whether or not they need to meet the requirements of EPAct, and, if so, the percentage of new vehicle purchases needed to comply with the law. The tool provides detailed specifications on available OEM alternative fuel vehicles, including the purchase cost of the vehicles, fuel and fuel system characteristics, and incentives and rebates surrounding the purchase of each vehicle. The full set of federal, state, and local incentives is made available through the tool, as well as detailed access to refueling site and dealership locations.

In 2015 the U.S. Environmental Protection Agency (EPA) and the U.S. Department of Transportation's National Highway Traffic Safety Administration (NHTSA) proposed a new steady-state engine dynamometer test procedure by which heavy-duty engine manufacturers would be required to create engine fuel rate versus engine speed and torque “maps”.[1] These maps would then be used within the agencies' Greenhouse Gas Emission Model (GEM)[2] for full vehicle certification to the agencies' proposed heavy-duty fuel efficiency and greenhouse gas (GHG) emissions standards. This paper presents an alternative to the agencies' proposal, where an engine is tested over the same duty cycles simulated in GEM. This paper explains how a range of vehicle configurations could be specified for GEM to generate engine duty cycles that would then be used for engine testing.

A modified constant volume sampling (CVS) system has been used to sample fugitive hydrocarbon (HC) emissions to determine whether such systems can help identify excess vehicular HC sources, such as leaking gas caps. The approach was successful in distinguishing tightly sealed, marginally leaking and grossly leaking caps. The technique may be useful in motor vehicle inspection and maintenance (I/M) facilities as a less intrusive alternative to techniques requiring pressurization of the fuel system.

Three alternatives to internal combustion vehicles currently being researched, developed, and commercialized are electric, hybrid electric, and fuel-cell vehicles. A total life-cycle inventory for an alternative vehicle must include factors such as the impacts of car body materials, tires, and paints. However, these issues are shared with gasoline-powered vehicles; the most significant difference between these vehicles is the power source. This paper focuses on the most distinct and challenging aspect of alternative-fuel vehicles, the power sources. The life-cycle impacts of battery systems for electric and hybrid vehicles are assessed. Less data is publicly available on the fuel cell; however, we offer a preliminary discussion of the environmental issues unique to fuel cells. For each of these alternative vehicles, a primary environmental hurdle is the consumption of materials specific to the power sources.

Cummins Westport Inc. (CWI) released for production the latest version of its C8.3G natural gas engine, the C Gas Plus, in July 2001. This engine has increased ratings for horsepower and torque, a full-authority engine controller, wide tolerance to natural gas fuel (the minimum methane number is 65), and improved diagnostics capability. The C Gas Plus also meets the California Air Resources Board optional low-NOx (2.0 g/bhp-h) emission standard for automotive and urban buses. Two pre-production C Gas Plus engines were operated in a Viking Freight fleet for 12 months as part of the U.S. Department of Energy's Fuels Utilization Program. In-use exhaust emissions, fuel economy, and fuel cost were collected and compared with similar 1997 Cummins C8.3 diesel tractors. CWI and the West Virginia University developed an ad-hoc test cycle to simulate the Viking Freight fleet duty cycle from in-service data collected with data loggers.

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.

Due to continuing reductions in EPA's emission standard values for exhaust particulate emissions, industry production has shifted towards engines that produce very low amounts of particulate emissions. Thus, it is very possible that future engines will challenge the error range of the current instrumentation and procedures used to measure particulate emissions by being designed to produce extremely low levels of particulates. When low particulate emitting engines are sampled at low flowrates, the resulting filter loadings may violate the minimum filter loading recommendation in the Heavy Duty Federal Test Procedure [1]. Conversely, higher flow rates may be an inappropriate option for increasing filter loading due to the possibility of stripping volatile organic compounds from the particulate sample or otherwise artificially reducing the accumulated mass [2].

The advent of emission control technology has resulted in significant changes in both the total mass and detailed patterns of hydrocarbons emitted from automobiles. Emission rates of 56 hydrocarbons from 22 motor vehicles, including catalyst and noncatalyst configurations, were determined for the Federal Urban Driving Cycle. An increased relative abundance of methane is indicated for vehicles equipped with oxidation catalysts. In view of the photochemically non-reactive nature of methane, simple and economic procedures for determination of vehicle nonmethane hydrocarbon emission rates are evaluated. In general the procedures evaluated require independent total hydrocarbon and methane analysis, with the nonmethane hydrocarbon level calculated by difference. The procedures are evaluated by comparison of indicated nonmethane hydrocarbon emission rates with rates obtained by summation of individual compound rates determined by advanced gas chromatographic procedures.