Comparison of emissions of transit buses using methanol and diesel fuel

Conference · Sat Dec 31 23:00:00 EST 1988

OSTI ID:5225542

Rajan, J B; Santini, D J

This paper provides a summary review of several comparative studies on the emission characteristics of methanol- and diesel-fueled buses. In order to facilitate comparison, the emissions data at idle and various driving cycles are presented on an hourly and/or per-mile basis. The results suggest that the substitution of methanol-fueled buses for clean diesel buses is not likely to result in net air-quality improvements during low-speed operations in an urban environment. Under these conditions, the negative effects of increases in carbon monoxide, formaldehyde, and hydrocarbons may offset the positive effects of particulate emissions reduction. However, for higher average driving speeds, the results to date are more promising, suggesting that methanol-fueled buses with well-operating catalysts offer net emissions benefits when substituted for old and recent-model diesel buses. This paper makes no attempt to weight emissions or to estimate air quality and does not estimate net emissions benefits. It is shown that pollutant-specific emissions from the test methanol vehicles are highly variable with average speed and are dependent on the engine technology and the emission-control devices used. It is also shown that the change in emissions resulting from the substitution of a methanol bus for a diesel bus can often be positive or negative for a single pollutant, depending on how the buses are driven. In general, methanol does not ignite under compression as easily as does diesel fuel, leading to relatively poor emissions performance by methanol buses when those buses spend a great deal of time at idle or at low engine load and vehicle speed. 18 refs., 19 figs., 4 tabs.

• Research Organization: Argonne National Lab., IL (USA)
• Sponsoring Organization: DOE/EH; DOT
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 5225542
• Report Number(s): CONF-900121-5; ON: DE90005652
• Country of Publication: United States
• Language: English

Related Subjects

29 ENERGY PLANNING, POLICY, AND ECONOMY
290300* -- Energy Planning & Policy-- Environment
Health
& Safety
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
320203 -- Energy Conservation
Consumption
& Utilization-- Transportation-- Land & Roadway
54 ENVIRONMENTAL SCIENCES
540120 -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
AIR QUALITY
ALCOHOL FUELS
ALDEHYDES
BUSES
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CHALCOGENIDES
CHEMICAL ANALYSIS
COMPARATIVE EVALUATIONS
COMPILED DATA
DATA
DIESEL FUELS
ELEMENTS
EMISSION
ENVIRONMENTAL EFFECTS
ENVIRONMENTAL QUALITY
FORMALDEHYDE
FUELS
HAZARDS
HEALTH HAZARDS
HYDROCARBONS
INFORMATION
KETONES
MATERIALS
METALS
METHANOL FUELS
NITROGEN COMPOUNDS
NITROGEN OXIDES
NUMERICAL DATA
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PARTICLES
PARTICULATES
PERFORMANCE TESTING
PETROLEUM PRODUCTS
PLATINUM
PLATINUM METALS
POLLUTANTS
RECOMMENDATIONS
STANDARDS
SYNTHETIC FUELS
TECHNOLOGY ASSESSMENT
TEMPERATURE EFFECTS
TESTING
TOXIC MATERIALS
TRANSITION ELEMENTS
TRANSPORTATION SYSTEMS
VEHICLES