The first round of emissions testing of flexible fuel methanol vehicles from the U.S. federal fleet was completed in 1995. The vehicles tested include 71 flexible fuel M85 1993 Dodge Spirits, 16 flexible fuel 1994 M85 Ford Econoline Vans, and a similar number of standard gasoline Dodge Spirits and E150 Ford Econoline Vans. Results presented include a comparison of regulated exhaust and evaporative emissions and a discussion of the levels of air toxins, and the ozone-forming potential (OFP) of the measured emissions.
Three private emissions laboratories tested vehicles taken from the general population of federal fleet vehicles in the Washington D.C., New York City, Detroit, Chicago, and Denver metropolitan regions. Testing followed the standard U.S. Environmental Protection Agency's Federal Test Procedures (FTPs) and detailed fuel changeover procedures as developed in the Auto/Oil Air Quality Improvement Research Program. Flexible fuel vehicles (FFVs) were tested using fuels consisting of 85% methanol to 15% gasoline (M85), 50% methanol to 50% gasoline (M50), and California Phase 2 reformulated gasoline (RFG).
All vehicle/fuel combinations showed emissions well below the certification standards (including the more stringent Tier I standards). At these levels, the magnitude of the fuel-to-fuel differences in emissions from FFVs was relatively low. In general, there appeared to be a small drop in non-methane hydrocarbons (NMHCs), and carbon monoxide (CO), and an increase in oxides of nitrogen (NOx) for M85 compared to the same vehicles tested on RFG. The OFP (expressed in grams of ozone per mile) from the M85 tests were 40% to 50% lower than the RFG tests performed on the Dodge Spirits and Ford Econoline vans. The M85 tests also showed lower levels of benzene and 1,3-butadiene but increased formaldehyde.