Effects of 10% biofuel substitution on ground level ozone formation in Bangkok, Thailand

• Published in: Atmospheric environment (1994) 2009-12, Vol.43 (37), p.5962-5970
• Main Authors: Milt, Austin, Milano, Aaron, Garivait, Savitri, Kamens, Richard
• Format: Article
• Language: English
• Subjects: Applied sciences; Atmospheric pollution; Bangkok; Biodiesel; Earth, ocean, space; Ethanol substitution; Exact sciences and technology; External geophysics; Genetic algorithm optimization; Meteorology; Modeling ground level ozone; Pollution
• ISSN: 1352-2310; 1873-2844
• DOI: 10.1016/j.atmosenv.2009.07.062

The Thai Government's search for alternatives to imported petroleum led to the consideration of mandating 10% biofuel blends (biodiesel and gasohol) by 2012. Concerns over the effects of biofuel combustion on ground level ozone formation in relation to their conventional counterparts need addressing. Ozone formation in Bangkok is explored using a trajectory box model. The model is compared against O 3, NO, and NO 2 time concentration data from air monitoring stations operated by the Thai Pollution Control Department. Four high ozone days in 2006 were selected for modeling. Both the traditional trajectory approach and a citywide average approach were used. The model performs well with both approaches but slightly better with the citywide average. Highly uncertain and missing data are derived within realistic bounds using a genetic algorithm optimization. It was found that 10% biofuel substitution will lead to as much as a 16 ppb peak O 3 increase on these four days compared to a 48 ppb increase due to the predicted vehicle fleet size increase between 2006 and 2012. The approach also suggests that when detailed meteorological data is not available to run three dimensional airshed models, and if the air is stagnant or predominately remains over an urban area during the day, that a simple low cost trajectory analysis of O 3 formation may be applicable.