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The primary purpose of this study was to obtain gas-phase and particular matter (PM) emissions from newer Tier 4 final off-road construction equipment using a Portable Emissions Measurement System (PEMS). This information can be used to provide accurate estimates of emissions from off-road construction equipment under real-world scenarios. Emission measurements were made for 10 pieces of Tier 4 final construction equipment including 3 excavators, 3 wheel loaders, 2 crawler tractors and 2 backhoe/loaders. The duty cycles included a pre-defined combined sequence of a cold-start phase, trenching, backfilling, travelling, and idling. For all types of equipment, the highest emissions were seen for the cold start phase, which showed NOx emissions levels ranging from 3.4 to 6.3 g/bhp-hr, from 15.8 to 26.1 g/kg-fuel and from 107 to 249 g/hour, with an average exhaust temperature around 100°C.The next highest emissions were found for the travel mode.

With funding from the California Energy Commission, the California Hybrid, Efficient and Advanced Truck Research Center, contracted with the University of California, Riverside's College of Engineering to evaluate the performance of a Class 5 battery electric urban delivery vehicle over two standardized driving cycles and a steady state range test on a chassis dynamometer. The test vehicle, a Smith Electric Newton Step Van, was equipped with a proprietary data acquisition system which was set to record a wide variety of vehicle parameters at a 1 Hz sampling period. In addition, the chassis dynamometer was set to measure and record additional parameters. Lastly, a portable J1772 EVSE recorded both grid energy and power at 15-minute intervals. This project provides a controlled test evaluation of the Smith Electric Newton Step Van. It recognizes the vehicle's potential for a successful delivery vehicle and identifies several important findings and areas that will need further research.

Biofuels, such as ethanol and butanol, have been the subject of significant political and scientific attention, owing to concerns about climate change, global energy security, and the decline of world oil resources that is aggravated by the continuous increase in the demand for fossil fuels. This study evaluated the potential emissions impacts of different alcohol blends on a fleet of modern gasoline vehicles. Testing was conducted on a fleet of nine vehicles with different combinations of ten fuel blends over the Federal Test Procedure and Unified Cycle. The vehicles ranged in model year from 2007-2014 and included four vehicles with port fuel injection (PFI) fueling and five vehicles with direct injection (DI) fueling. The ten fuel blends included ethanol blends at concentrations of 10%, 15%, 20%, 51%, and 83% by volume and iso-butanol blends at concentrations of 16%, 24%, 32%, and 55% by volume, and an alcohol mixture giving 10% ethanol and 8% iso-butanol in the final blend.

Emissions, fuel economy, and performance are determined over a light and a heavy driving cycle designed to represent the vehicles in-use driving patterns. The vehicles are 2010 class 8 Freightliner tractor trucks equipped with Cummins engines with Selective Catalytic Reduction and Diesel Particulate Filter emission control systems. The hybrid has lower carbon dioxide emissions, better fuel economy, and nitrogen oxide emissions statistically the same as the conventional. The CO emissions are well below the standards for both vehicles, but they are higher from the hybrid. The higher CO emissions for the hybrid are primarily related to the cooling of the Diesel Oxidation Catalyst (DOC) during the standard 20 minute key-off soak between repeats of the driving cycles. With a 1 minute key-off soak the CO emissions from the hybrid are negative.

Gasoline direct injection (GDI) engines have improved thermodynamic efficiency (and thus lower fuel consumption) and power output compared with port fuel injection (PFI) and their penetration is expected to rapidly grow in the near future in the U.S. market. In addition, the use of alternative fuels is expanding, with a potential increase in ethanol content beyond the current 10%. Increased emphasis has been placed on butanol due to its more favorable fuel properties, as well as new developments in production processes. This study explores the influence of mid-level ethanol and iso-butanol blends on criteria emissions, gaseous air toxics, and particulate emissions from two wall-guided gasoline direct injection passenger cars fitted with three-way catalysts. Emission measurements were conducted over the Federal Test Procedure (FTP) driving cycle on a chassis dynamometer.

Engine manufacturers have explored many routes to reducing the emissions of harmful pollutants and conserving energy resources, including development of after treatment systems to reduce the concentration of pollutants in the engine exhaust, using alternative fuels, and using alternative fuels with after treatment systems. Liquefied petroleum gas (LPG) is one alternative fuel in use and this paper will discuss emission measurements for several LPG vehicles. Regulated emissions were measured for five school buses, one box truck, and two small buses over a cold start Urban Dynamometer Driving Schedule (CS_UDDS), the Urban Dynamometer Driving Schedule (UDDS), and the Central Business District (CBD) cycle. In general, there were no significant differences in the gas phase emissions between the UDDS and the CBD test cycles. For the CS-UDDS cycle the total hydrocarbons and non-methane hydrocarbon emissions are higher than they are from the UDDS cycle.

The introduction of biofuels is seen as a very important measure to reduce the emissions of greenhouse gases from the transport sector. Currently, ethanol is the most widely used renewable fuel for transportation in the US and with the push to use increasingly higher levels of renewable fuels, there has been an accompanying push to further increase the ethanol level in gasoline. In addition to ethanol, butanol, an alcohol which can be produced from biomass sources, has recently received more attention as an alternative to gasoline for use in spark ignition (SI) engines. For this study, two 2007 model year and one 2012 model year light-duty vehicles equipped with a three-way catalyst (TWC) were employed. For the 2007 model year vehicles, emissions and fuel economy measurements were made for E10 (reference fuel), E15, E20, and B16 fuels. The latter corresponds to a blend of gasoline and 16% of butanol, which is the equivalent of E10 in terms of oxygen content.