Search Results

As GHG and fuel economy regulations of light-duty vehicles have become more stringent, advanced emissions reduction technology has extensively penetrated the US light-duty vehicle fleet. ...The Environmental Protection Agency (EPA) has previously used its Advanced Light-Duty Powertrain and Hybrid Analysis (ALPHA) full vehicle simulation tool to evaluate the greenhouse gas (GHG) emissions of light-duty vehicles. ALPHA contains a library of benchmarked powertrain components that can be matched to specific vehicles to explore GHG emissions performance. ...ALPHA contains a library of benchmarked powertrain components that can be matched to specific vehicles to explore GHG emissions performance. Recently, EPA has updated the ALPHA model with key changes including the addition of new models for electrified vehicle architectures and a robust structure which allows batch processing of large numbers of simulations.

In addition to NOX emissions, greenhouse gas (GHG), CO2 and methane emissions regulations from heavy-duty engines are also becoming more stringent. ...Results from this study demonstrate a potential pathway to achieving ultra-low NOX emissions and future GHG Phase 2 standards on heavy-duty vehicles.

For the US market, an abundant supply of natural gas (NG) coupled with recent green-house gas (GHG) regulations have spurred renewed interest in dual-fuel combustion regimes. This paper explores the potential of co-direct injection to improve the efficiency and reduce the methane emissions versus equivalent fumigated dual-fuel combustion systems.

The CO2 advantage coupled with the low NOX and PM potential of natural gas (NG) makes it well-suited for meeting future greenhouse gas (GHG) and NOX regulations for on-road medium and heavy-duty engines. However, because NG is mostly methane, reduced combustion efficiency associated with traditional NG fueling strategies can result in significant levels of methane emissions which offset the CO2 advantage due to reduced efficiency and the high global warming potential of methane.