Influence of road and traffic conditions on fuel consumption and fuel cost for different bus technologies

In this paper, the influences of road and traffic conditions on fuel consumption and fuel costs of conventional diesel, parallel hybrid and stoichiometric CNG buses in intercity bus service are analysed. Calculation of fuel consumption and fuel costs for these three different bus technologies was conducted for road network of the Republic of Serbia. Three scenarios were considered. The first scenario includes bus traffic volume carried out on the road network in 2014. The other two scenarios are characterized by the decrease i.e. increase of traffic volume by 20% with unchanged state of road infrastructure in comparison to the year 2014. Obtained results show that in intercity bus service the greatest influence on the fuel consumption of buses has operating speed of the bus, followed by terrain type on which buses operate. The impact of other factors (international roughness index, fluctuation of traffic volume by 20% and correction factors of fuel consumption) is less pronounced. In various operating conditions the fuel cost savings per 100 km of CNG buses compared to diesel buses are in the range of €8.84-12.16. These cost saving for hybrid buses compared to diesel buses are in the range of €3.33-7.27.