Research Projects

Project at a Glance

Project Status: complete

Report Published February 1994:

Title: Effects of use of low-oxygenate gasoline blends upon emissions from California vehicles

Principal Investigator / Author(s): Born, Gerald L.

Contractor: Automotive Testing Laboratories

Contract Number: a932-159

Research Program Area: Emissions Monitoring & Control

Topic Areas: Mobile Sources & Fuels, Stationary Sources


The objective of this study was to determine the effects of oxygenated fuels on regulated emissions (hydrocarbons, HCs; carbon monoxide, CO; and oxides of nitrogen, NOx) and unregulated emissions (speciated HCs, carbonyl compounds, and alcohols) from California vehicles under summer and winter conditions. Both exhaust and evaporative test sequences were included using a fleet of in use, California emission certified vehicles drawn from a wide range of emission control techniques. The test results obtained were examined statistically to address six specific questions concerning the use of oxygenated fuels:

1. Do slight increases in NOx emission offset the benefit of HC and CO reductions attributable to the oxygenate?
2. Do different vehicle technologies respond differently to the oxygenates?
3. How do the oxygenated fuel effects change with the driving cycle?
4. What is the emission impact of splash blending of ethanol versus RVP match blending of ethanol?
5. Do increased emissions of toxic materials due to the oxygenates offset reductions in the regulated pollutants?
6. What are the temperature and fuel blend season effects on emissions from the oxygenated fuels?


For questions regarding this research project, including available data and progress status, contact: Heather Choi at (916) 322-3893

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