A Methodology on Analyzing Fuel Saving with Idling Stop

In order to estimate the effect of idling stop on fuel saving, in this work, a methodology to calculate the fuel saving was proposed and analyzed. Since it is very impractical to estimate the fuel saving from the daily recorded fuel filling amount, a fuel saving was calculated using the fuel consumption for both idling and engine start-up. A standard test with NIER-07 mode was carried out to validate the proposed method of this work, and showed a good agreement between the measurement and calculation of fuel saving owing to idling stop. Measured data from in-use city bus was used to estimate the fuel saving from idling stop. Also, an analysis of real driving data showed that the maximum execution rate of idling stop would be about 75%. This corresponds to about 8.7% of fuel saving based on the total fuel consumption without idling stop. Finally, an equation to estimate the fuel saving for city buses was made, which has about 5.7% of deviation.