scholarly journals Performance, Cost, and Market Share of Conventional Vehicle Efficiency Technologies?: Retrospective Comparison of Regulatory Document Projections for Corporate Average Fuel Economy and Greenhouse Gas Standards

2017 ◽  
Vol 2628 (1) ◽  
pp. 67-77 ◽  
Author(s):  
Fei Xie ◽  
Zhenhong Lin ◽  
Rachael Nealer
Keyword(s):  
Greenhouse Gas ◽  
Fuel Economy ◽  
Gasoline Engine ◽  
Vehicle Body ◽  
Corporate Average Fuel Economy ◽  
Conventional Vehicle ◽  
Retrospective Comparison ◽  
Vehicle Efficiency ◽  
Gas Standards ◽  
Current Energy

This study conducted an analysis of regulatory documents on current energy- and greenhouse gas–relevant conventional vehicle efficiency technologies in the corporate average fuel economy standards (2017 to 2025) and greenhouse gas rulemaking context by NHTSA and EPA. The focus was on identifying what technologies today—as estimated now (2015 to 2016)—receive higher or lower expectations with regard to effectiveness, cost, and consumer adoption than what experts projected during the 2010 to 2011 rulemaking period. A broad range of conventional vehicle efficiency technologies, including gasoline engine and diesel engine, transmission, accessory, hybrid, and vehicle body technologies, was investigated in this analysis. Most assessed technologies were found to have had better competitiveness than expected with regard to effectiveness or costs, or both, with costs and market penetration more difficult to predict than technology effectiveness.

U.S. fuel economy and greenhouse gas standards: What have they achieved and what have we learned?

Energy Policy ◽  
2020 ◽  
Vol 146 ◽  
pp. 111783
Author(s):  
David L. Greene ◽  
Judith M. Greenwald ◽  
Rebecca E. Ciez
Keyword(s):  
Greenhouse Gas ◽  
Fuel Economy ◽  
Gas Standards

scholarly journals Policy Watch: Corporate Average Fuel Economy Standards

1992 ◽  
Vol 6 (2) ◽  
pp. 171-180 ◽  
Author(s):  
Robert W Crandall
Keyword(s):  
Carbon Dioxide ◽  
Global Warming ◽  
Greenhouse Gas ◽  
Fuel Economy ◽  
Carbon Tax ◽  
Empirical Literature ◽  
Oil Shocks ◽  
Corporate Average Fuel Economy ◽  
The Past ◽  
Policy Watch

Initially, the minimum corporate average fuel economy (CAFE) program was promoted as a policy to reduce U.S. vulnerability to oil shocks. In the past two years, however, concern about global warming has resulted in new political pressures to raise CAFE once again to reduce the growth in U.S. emissions of carbon dioxide, a greenhouse gas. In this paper, I do not attempt to provide a detailed critique of these two objectives. I simply take the goals as given and draw upon estimates from the empirical literature to show that CAFE is a very costly instrument for achieving them. In addition, I compare the costs of meeting the same objectives through a fuel or carbon tax.

Tumble Flow Measurements Using Three Different Methods and Its Effects on Fuel Economy and Emissions

2006 ◽  
Author(s):  
Myoungjin Kim ◽  
Sihun Lee ◽  
Wootae Kim
Keyword(s):  
Fuel Economy ◽  
High Performance ◽  
Gasoline Engine ◽  
Exhaust Emissions ◽  
Combustion Stability ◽  
Lean Burn ◽  
Flow Measurements ◽  
Part Load ◽  
Gasoline Engines ◽  
Dynamometer Test

In-cylinder flows such as tumble and swirl have an important role on the engine combustion efficiencies and emission formations. In particular, the tumble flow, which is dominant in-cylinder flow in current high performance gasoline engines, has an important effect on the fuel consumptions and exhaust emissions under part load conditions. Therefore, it is important to know the effect of the tumble ratio on the part load performance and optimize the tumble ratio of a gasoline engine for better fuel economy and exhaust emissions. First step in optimizing a tumble flow is to measure a tumble ratio accurately. In this research the tumble flow was measured, compared and correlated using three different measurement methods: steady flow rig, 2-Dimensional PIV, and 3-Dimensional PTV. Engine dynamometer test was performed to find out the effect of the tumble ratio on the part load performance. Dynamometer test results of high tumble ratio engine showed faster combustion speed, retarded MBT timing, higher exhaust emissions, and a better lean burn combustion stability. Lean limit of the baseline engine was expanded from A/F=18:1 to A/F=21:1 by increasing a tumble ratio using MTV.

Economy and emission characteristics of the optimal dilution strategy in lean combustion based on GDI gasoline engine equipped with prechamber

2021 ◽  
Vol 13 (12) ◽  
pp. 168781402110381
Author(s):  
Li Wang ◽  
Zhaoming Huang ◽  
Wang Tao ◽  
Kai Shen ◽  
Weiguo Chen
Keyword(s):  
Fuel Economy ◽  
Gasoline Engine ◽  
Direct Injection ◽  
Engine Performance ◽  
Gasoline Direct Injection ◽  
Dilution Ratio ◽  
Lean Combustion ◽  
Excess Air ◽  
Combustion Phase ◽  
Hc Emissions

EGR and excess-air dilution have been investigated in a 1.5 L four cylinders gasoline direct injection (GDI) turbocharged engine equipped with prechamber. The influences of the two different dilution technologies on the engine performance are explored. The results show that at 2400 rpm and 12 bar, EGR dilution can adopt more aggressive ignition advanced angle to achieve optimal combustion phasing. However, excess-air dilution has greater fuel economy than that of EGR dilution owing to larger in-cylinder polytropic exponent. As for prechamber, when dilution ratio is greater than 37.1%, the combustion phase is advanced, resulting in fuel economy improving. Meanwhile, only when the dilution ratio is under 36.2%, the HC emissions of excess-air dilution are lower than the original engine. With the increase of dilution ratio, the CO emissions decrease continuously. The NOX emissions of both dilution technologies are 11% of those of the original engine. Excess-air dilution has better fuel economy and very low CO emissions. EGR dilution can effectively reduce NOX emissions, but increase HC emissions. Compared with spark plug ignition, the pre chamber ignition has lower HC, CO emissions, and higher NO emissions. At part load, the pre-chamber ignition reduces NOX emissions to 49 ppm.

scholarly journals Evaluation of vehicle lightweighting to reduce greenhouse gas emissions with focus on magnesium substitution

2018 ◽  
Vol 16 (6) ◽  
pp. 869-888 ◽  
Author(s):  
Siddharth Kulkarni ◽  
David John Edwards ◽  
Erika Anneli Parn ◽  
Craig Chapman ◽  
Clinton Ohis Aigbavboa ◽  
...  
Keyword(s):  
Comparative Analysis ◽  
Greenhouse Gas Emissions ◽  
Greenhouse Gas ◽  
Fuel Economy ◽  
Internal Combustion Engines ◽  
Mechanical Performance ◽  
Material Design ◽  
Torsional Stiffness ◽  
Gas Emissions ◽  
Content Type

Purpose Vehicle weight reduction represents a viable means of meeting tougher regulatory requirements designed to reduce fuel consumption and control greenhouse gas emissions. This paper aims to present an empirical and comparative analysis of lightweight magnesium materials used to replace conventional steel in passenger vehicles with internal combustion engines. The very low density of magnesium makes it a viable material for lightweighting given that it is lighter than aluminium by one-third and steel by three-fourth. Design/methodology/approach A structural evaluation case study of the “open access” Wikispeed car was undertaken. This included an assessment of material design characteristics such as bending stiffness, torsional stiffness and crashworthiness to evaluate whether magnesium provides a better alternative to the current usage of aluminium in the automotive industry. Findings The Wikispeed car had an issue with the rocker beam width/thickness (b/t) ratio, indicating failure in yield instead of buckling. By changing the specified material, Aluminium Alloy 6061-T651 to Magnesium EN-MB10020, it was revealed that vehicle mass could be reduced by an estimated 110 kg, in turn improving the fuel economy by 10 per cent. This, however, would require mechanical performance compromise unless the current design is modified. Originality/value This is the first time that a comparative analysis of material substitution has been made on the Wikispeed car. The results of such work will assist in the lowering of harmful greenhouse gas emissions and simultaneously augment fuel economy.

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