A Comparison Study on Saving Fuel by Idle-Stop System in Bangkok Traffic Condition

This paper presents an investigation on fuel consumption in Bangkok traffic condition with an application of idle stop system. Collected data is evaluated by cutoff the fuel usage while the vehicle is in stationary condition. The vehicles in this study are ordinary vehicle which is not the vehicle with idle-stop system. The study includes four levels of congestion and three road side conditions. With idle stop system, for spark ignition engine 40% of fuel consumption rate could be improved in severe condition and 10% improvement in free flow traffic. In addition, the fuel consumption can be improved by 30% for compression ignition engine. Furthermore, the idle stop system improves fuel efficiency in severe congestion to the same level as the free flow traffic