Investigation into Fuel Economy and NOx Emissions of Light Duty Hybrid Truck in Real Traffic Conditions

Hybrid trucks are disseminated on the market in Japan. To bring out advantages of fuel economy and low emission, on-board measuring system for fuel consumption and NOx emissions was mounted in a light duty truck with a parallel hybrid system. Tests were carried out with various payloads on roads. As the results, advantages of the tested hybrid truck were shown from the actual data regarding the fuel economy and NOx emissions, considering regeneration energy by the hybrid system. Improvement of the fuel economy and NOx emissions was clearly observed in the running condition such as urban and suburban roads. From the analysis of regeneration energy during vehicle deceleration, it turned out that a longer slowdown time and a higher speed at which deceleration begins result in larger amount of energy regeneration, which means the improvement of fuel economy. For the improvement of roadside pollutions, the reduction of NOx emissions in running using the second gear position is desired.