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This technical paper collection focuses on the general topic of combustion engine gaseous emissions (regulated and non-regulated). This includes well-to-wheels CO2 production for alternative technologies, fuel economy and all greenhouse gas emission research. It also includes hydrocarbon species and specific NOx species production over aftertreatment devices as a result of changes in fuel specification and the inclusion of bio-derived components and consideration of secondary emissions production (slip) as a result of aftertreatment.

More specific, engines are required to reduce CO2 emissions by 6% compared to GHG phase 1 levels. Next to the GHG emission legislation, more stringent legislation is anticipated in the US to further reduce NOx emissions: a further 90% reduction is targeted as soon as 2024 compared to 2010 standard. ...Increasing efforts to minimize global warming has led to regulation of greenhouse gas (GHG) emissions of automotive applications. The US is frontrunner regarding implementation of GHG related legislation with the introduction of GHG phase 1 and phase 2, ultimately targeting a 40% fuel consumption reduction in 2027 compared to 2010 on vehicle level. ...The US is frontrunner regarding implementation of GHG related legislation with the introduction of GHG phase 1 and phase 2, ultimately targeting a 40% fuel consumption reduction in 2027 compared to 2010 on vehicle level.

When considered along with Phase 2 Greenhouse Gas (GHG) requirements, the proposed Air Resource Board (ARB) nitrogen oxide (NOx) emission limit of 0.02 g/bhp-hr will be very challenging to achieve as the trade-off between fuel consumption and NOx emissions is not favorable. ...Each of these engine models met the 2027 Phase 2 GHG emission standards but used a different combination of technologies, including downsizing, downspeeding, variable compression ratio (VCR), cylinder deactivation, and turbocompounding. ...The results show that with appropriate selection of engine and aftertreatment technology packages, the 2027 Phase 2 GHG emission standards and the proposed 2024 ultra-low NOx emission standards can be achieved simultaneously.

The aim of this study is to evaluate the land requirement, energy consumption and GHG (greenhouse gases) emissions of microalgal biodiesel (M-BD) and Jatropha curcas seeds (J-BD) based biodiesel from the perspective of life cycle assessment (LCA). ...The well to pump (WTP) stage for microalgal biodiesel had higher fossil energy requirement but lower petroleum energy consumption and GHG emissions compared to Jatropha curcas and conventional diesel (CD). The WTP energy efficiency for J-BD100 and M-BD 100 were 26% and 17.4%, respectively. ...The WTW results showed good performance for MBD100 on petroleum consumption and GHG emissions. The high fossil energy use for microalgae BD100 was attributed to the large inputs for microalgae growth, including fertilizer and process fuels.

The recent development of biofuel production worldwide is closely linked to GHG savings objectives and to regional agricultural policies. Many existing studies intend to evaluate the net non renewable energy and GHG savings associated to the various biofuel production pathways. ...Many existing studies intend to evaluate the net non renewable energy and GHG savings associated to the various biofuel production pathways. However, there is no consensus on the results of those studies. ...The main explanations of variations among the results are the following: energy consumption and GHG emissions of the reference fossil pathway, data used for the representation of farming processes and biofuel production processes, accounting for carbon storage in agricultural soils, reference use of the land, choice of an allocation method in case of coproduction.

Electricity from renewable sources realized the largest reductions in petroleum energy use and GHG emissions for all PHEVs as AER increased. GHG emissions benefits may not be realized for PHEVs employing biomass-based fuels, e.g., biomass-E85 and -hydrogen, over regular HEVs if the marginal mix is dominated by fossil sources. ...The Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model incorporated fuel economy and electricity use of alternative fuel/vehicle systems simulated by the Powertrain System Analysis Toolkit (PSAT) to conduct a well-to-wheels (WTW) analysis of energy use and greenhouse gas (GHG) emissions of plug-in hybrid electric vehicles (PHEVs). Based on PSAT simulations of the blended charge depleting (CD) operation, grid electricity accounted for a share of the vehicle’s total energy use ranging from 6% for PHEV 10 to 24% for PHEV 40 based on CD vehicle mile traveled (VMT) shares of 23% and 63%, respectively. ...Besides fuel economy of PHEVs and type of on-board fuel, the type of electricity generation mix impacted the WTW results of PHEVs, especially GHG emissions. For an all-electric range (AER) between 10 to 40 miles, PHEVs employing petroleum fuels (gasoline and diesel), a blend of 85% ethanol and 15% gasoline (E85), and hydrogen were shown to offer 40–60%, 70–90%, and over 90% reduction in petroleum energy use, and 30–60%, 40–80%, and 10–100% reduction in GHG emissions, respectively, relative to an internal combustion engine vehicle (ICEV) using gasoline.

Historically, greenhouse gas (GHG) emissions standards for vehicles have focused on tailpipe emissions. However, sound environmental policy requires a more holistic well-to-wheels (WTW) assessment that includes both production of the fuel and its use in the vehicle. ...The present research explores the net change in WTW GHG emissions associated with moving from regular octane (RO) to high octane (HO) gasoline. It considers both potential increases in refinery emissions from producing HO fuel and potential reductions in vehicle emissions through the use of fuel-efficient engines optimized for such fuel. ...Two engine designs were considered: one which could take little advantage of higher octane fuel to increase efficiency, and one which could be adjusted further to take advantage of the higher octane. WTW GHG emissions were analyzed within a life cycle analysis framework, where the upstream emissions of raw material and utility inputs to the refinery were added to the direct refinery emissions and product combustion emissions from the vehicle.

., EPA and NHTSA have issued a joint proposed GHG rule that sets limits for CO2 and other GHGs from pick-up trucks and vans, vocational vehicles, semi-tractors, and heavy duty diesel engines. ...This work focuses on the new U.S. regulation of greenhouse gas (GHG) emissions from commercial vehicles and diesel engines and the most likely technologies to meet future anticipated standards while improving transportation freight efficiency. ...This paper discusses and compares different technologies to meet GHG regulations for diesel engines based on considerations of cost, complexity, real-world fidelity, and environmental benefit.

Nitrous oxide (N2O), with a global warming potential (GWP) of 297 and an average atmospheric residence time of over 100 years, is an important greenhouse gas (GHG). In recognition of this, N2O emissions from on-highway medium- and heavy-duty diesel engines were recently regulated by the US Environmental Protection Agency (EPA) and National Highway Traffic Safety Administration’s (NHTSA) GHG Emission Standards. ...In recognition of this, N2O emissions from on-highway medium- and heavy-duty diesel engines were recently regulated by the US Environmental Protection Agency (EPA) and National Highway Traffic Safety Administration’s (NHTSA) GHG Emission Standards. Unlike NO and NO2, collectively referred to as NOx, N2O is not a major byproduct of diesel combustion. ...Engine-based results show that N2O emissions for this nonroad engine and aftertreatment system are below the current 0.1 g/bhp·hr on-highway GHG standard. To better understand the processes which contribute to the system-level N2O emissions seen during engine testing, reactor-based experiments were conducted to elucidate the fundamental component-level mechanisms responsible for N2O formation.

Using a transportation fuel-cycle model developed at ANL with data collected on vehicle fuel economy from the two events as well as electric generation mix data from the utilities that provided the electricity to charge the EVs on the two Tours, we estimated full fuel-cycle energy use and GHG emissions of EVs and CVs. This paper presents the data, methodology, and results of this study, including the full fuel-cycle energy use and GHG emission reduction potential of the EVs operating on the Tour. ...This paper presents the data, methodology, and results of this study, including the full fuel-cycle energy use and GHG emission reduction potential of the EVs operating on the Tour.

Light-duty vehicle greenhouse gas (GHG) and fuel economy (FE) standards for MYs 2012-2025 are requiring vehicle powertrains to become much more efficient. ...One key technology strategy that vehicle manufacturers are using to help comply with GHG and FE standards is to replace naturally aspirated engines with smaller displacement “downsized” boosted engines.

The proposed US LD (light-duty) greenhouse gas (GHG) regulation for 2017-25 is reviewed, as well as the finalized, first-ever, US HD (heavy-duty) GHG rule for 2014-17. ...The proposed US LD (light-duty) greenhouse gas (GHG) regulation for 2017-25 is reviewed, as well as the finalized, first-ever, US HD (heavy-duty) GHG rule for 2014-17. The paper then gives a brief, high-level overview of key emissions developments in LD and HD engine technology, covering both gasoline and diesel. ...Emissions challenges include lean NOx remediation for diesel and lean-burn gasoline to meet both the emerging NOx and GHG regulations. NOx control technologies are then summarized, including SCR (selective catalytic reduction) with ammonia, and hydrocarbon-based approaches.

Both announced new legislation for CO2, Greenhouse Gas (GHG) Phase II. CARB is also planning additional Ultra Low NOx regulations. Both regulations are significant and will require a number of technologies to be used in order to achieve the challenging limits.

In this work, we conduct a well-to-wheels (WTW) analysis of the greenhouse gas (GHG) emissions and energy use of the potential LOF GCI vehicle technology. A detailed linear programming (LP) model of the US Petroleum Administration for Defense District Region (PADD) III refinery system - which produces more than 50% of the US refined products - is modified to simulate the production of the LOF in petroleum refineries and provide product-specific energy efficiencies. ...Taking into account a 25% fuel economy gain relative to the regular gasoline internal combustion engine vehicle (ICEV), the per-mile-based WTW GHG emissions of the LOF GCI ICEV are estimated to be 22% and 9% lower than those of the today’s gasoline and diesel ICEVs, respectively; and the per-mile-based WTW fossil energy use is 18% and 6% lower than gasoline and diesel ICEVs, respectively.

The US finalized LD (light-duty) greenhouse gas (GHG) regulation for 2017-25. The paper then gives a brief, high-level overview of key developments in LD and HD engine technology, covering both gasoline and diesel. ...Marked improvements in engine efficiency are summarized for gasoline and diesel engines to meet both the emerging NOx and GHG regulations. HD engines are just starting to demonstrate 50% brake thermal efficiency. NOx control technologies are then summarized, including SCR (selective catalytic reduction) with ammonia, and hydrocarbon-based approaches.

As part of the midterm evaluation of the 2022-2025 light-duty GHG emissions rule, the Environmental Protection Agency (EPA) has been evaluating fuel efficiency data from tests on newer model engines and vehicles. ...The data is used as inputs to an EPA vehicle simulation model created to estimate greenhouse gas (GHG) emissions from light-duty vehicles. The Advanced Light Duty Powertrain and Hybrid Analysis (ALPHA) model is a physics-based, full vehicle computer simulation capable of analyzing various vehicle types with different powertrain technologies and showing realistic vehicle behavior and auditing of all internal energy flows in the model.

Besides those efforts paid for sheer improvements of genuine vehicle technologies, NISSAN testified that “connectivity” with outside servers contributed a lot to reduce fuel consumption, thus the less emission of GHG, with two major factors; 1. detouring the traffic congestions with the support of probe-based real-time traffic information and 2. providing Eco-driving advices for the better driving behavior to prompt the better usage of energy.

Biofuels offer the benefits of lower and even negative GHG emissions, sustainability, and domestic fuel production. The herbaceous and woody biomass–based ethanol options are more attractive than producing ethanol and biodiesel from food products.

The formation of these salts can reduce the availability of NH3 for NOx conversion, block active catalyst sites, and result in the formation of N2O, a regulated Greenhouse Gas (GHG). In this study, we investigate the effect of hydrothermal aging on the formation and decomposition of ammonium nitrate on a state-of-the-art Cu/zeolite selective catalytic reduction (SCR) catalyst.

This study emphasizes the fact that there lies value and potential savings in harmonizing some of the inherent differences between the USA, EU, and China regulations with respect to the role of vehicle mass and lightweighting within Fuel Economy (FE) and Green House Gas (GHG) regulations. The definition and intricacies of FE and mass regulations for the three regions (USA, EU, and China) have been discussed and compared.