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Speciated exhaust emission data from Phase I of the Auto/Oil Air Quality Improvement Research Program are presented and analyzed. Eighteen fuels were tested which varied in four fuel parameters: aromatics, MTBE content, olefins, and T90. These fuels were tested in two fleets of vehicles. One consisted of twenty 1989 vehicles and the other consisted of fourteen 1983-1985 vehicles. The 1990 version of Carter reactivity factors were used to calculate reactivities for each of these tests. Two types of reactivities were calculated. The first was Specific Reactivity and has units of grams ozone per gram NMOG (non-methane organic gas). The second was Ozone Forming Potential and has units of grams ozone per mile. Both types of reactivities were calculated using Carter's MIR (Maximum Incremental Reactivity) as well as MOR (Maximum Ozone Reactivity) factors.

This report presents the Auto/Oil AQIRP results of a methanol fueled vehicle emission study. Nineteen early prototype flexible/variable fueled vehicles (FFV/VFV) were emission tested with industry average gasoline (M0), an 85% methanol-gasoline blend (M85), and a splash-blend of M85 with M0 (gasoline) giving 10% methanol (M10). Vehicle emissions were analyzed for the FTP exhaust emissions, SHED diurnal and hot soak evaporative emissions, and running loss evaporative emissions. Measurements were made for HC, CO and NOx emissions and up to 151 organic emission species, including air toxic components. M0 and M10 emissions were very similar except for elevated M10 evaporative emissions resulting from the high M10 fuel vapor pressure. M85 showed lower exhaust emissions than M0 for NMHC (non-methane hydrocarbon), OMHCE (organic material hydrocarbon equivalent), CO and most species. M85 had higher exhaust emissions for NMOG (non-methane organic gases), NOx, methanol and formaldehyde.

Exhaust and evaporative emissions were measured as a function of gasoline composition and fuel vapor pressure in a fleet of 20 1989 vehicles. Eleven fuels were evaluated; four hydrocarbon only, four splash blended ethanol fuels (10 vol %), two methyl tertiary-butyl ether (MTBE) blends (15 vol %) and one ethyl tertiary-butyl ether (ETBE) blend (17 vol %). Reid vapor pressures were between 7.8 and 9.6 psi. Exhaust emission results indicated that a reduction in fuel Reid vapor pressure of one psi reduced exhaust HC and CO. Adding oxygenates reduced exhaust HC and CO but increased NOx. Results of evaporative emissions tests on nineteen vehicles indicated a reduction in diurnal emissions with reduced Reid vapor pressure in the non-oxygenated and ethanol blended fuels. However, no reduction in diurnal emissions with the MTBE fuel due to Reid vapor pressure reduction was observed. Reducing Reid vapor pressure had no statistically significant effect on hot soak emissions.

The objective of this project was to assess the effects of various blends of biodiesel on locomotive engine exhaust emissions. Systematic, credible, and carefully designed and executed locomotive fuel effect studies produce statistically significant conclusions are very scarce, and only cover a very limited number of locomotive models. Most locomotive biodiesel work has been limited to cursory demonstration programs. Of primary concern to railroads and regulators is understanding any exhaust emission associated with biodiesel use, especially NOX emissions. In this study, emissions tests were conducted on two locomotive models, a Tier 2 EMD SD70ACe and a Tier 1+ GE Dash9-44CW with two baseline fuels, conventional EPA ASTM No. 2-D S15 (commonly referred to as ultra-low sulfur diesel - ULSD) certification diesel fuel, and commercially available California Air Resource Board (CARB) ULSD fuel.

Fuel economy measurements from portions of Phase I of the Auto/Oil Air Quality Improvement Research Program were analyzed. The following fuel variables were examined: aromatics, olefins, T90, RVP, and various oxygenates (MTBE, ETBE and ethanol). Two vehicle fleets were tested: twenty 1989 vehicles and fourteen 1983-1985 vehicles. Three measures of fuel economy were analyzed. EPA Fuel Economy used the calculation defined in the Federal Register and is an attempt to correct for changes in fuel properties. Volumetric Fuel Economy is based on a carbon balance calculation and is a measure of the actual volume of gasoline burned. Energy Specific Fuel Economy is a measure of fuel economy based on energy content. The following fuel changes resulted in reductions of Volumetric Fuel Economy in both fleets: reduced aromatics, reduced olefins, reduced T90, and addition of oxygenates. Changes in RVP did not have a significant effect on fuel economy.

Exhaust and hot soak evaporative emissions were measured in a fleet of 1993 production flexible/variable-fueled vehicles on methanol fuels blended with a reformulated gasoline. A fleet of 1993 California Tier 1 gasoline vehicles was also tested on the same reformulated gasoline blended to meet the specifications of California Phase 2 fuel. Ozone-forming reactivity, expressed as reactivity weighted emissions and specific reactivity, was calculated using 1991 SAPRC and 1994 CBM MIR and MOR factors. Within the FFV/VFV fleet, FTP exhaust and reactivity weighted emissions were significantly lower by 18 to 32% with Phase 2 gasoline relative to Industry Average gasoline. With the exception of greater NMOG emissions with the M85 blends, and lower OMHCE emissions with M85 blended with Industry Average gasoline, exhaust organic emissions, CO and NOx with the methanol fuels were not significantly different than their base gasolines.

Exhaust and evaporative emissions from three flexible/variable fuel vehicles (FFV/VFV) were measured as the vehicles operated on E85 fuel (a mixture of 85% ethanol and 15% gasoline) or on gasoline. One vehicle was a production vehicle designed for ethanol fuels and sold in 1992-93 and the other two vehicles were prototypes which were recalibrated 1992 model year methanol FFV's. The gasolines tested were Industry Average Fuel A and a reformulated gasoline Fuel C2 that met California 1996 regulatory requirements. The gasoline component of Fuel E85 was based on the reformulated gasoline. The major findings from this three-vehicle program were that E85 reduced NOx 49% compared to Fuel A and 37% compared to Fuel C2, but increased total toxics 108% (5 mg/mi) and 255% (20 mg/mi), respectively, primarily by increasing acetaldehyde. The NOx effect was significant for both engine-out and tailpipe emissions.