For the reduction of greenhouse gas emission in the
transportation sector, various countermeasures against CO₂ emission
have been taken. The eco-driving has been paid attention because of
its immediate effect on the CO₂ reduction. Eco-driving is defined
as a driving method with various driving techniques to save fuel
economy. The eco-driving method has been promoted to the common
drivers as well as the drivers of carriers. Additionally, there are
many researches about improvement of fuel efficiency and CO₂
reduction. However, the eco-driving will have the reduction effect
of CO₂ emission, the influence of the eco-driving on air pollutant
emission such as NOx is not yet clear.
In this study, the effect of the eco-driving on real-world
emission has been analyzed using the diesel freight vehicle with
the on-board measurement system. In the test, two drivers drove the
one diesel freight vehicle in the same route; one driver drove the
vehicle normally, and another one drove it with the early shift-up
driving. The CO₂ reduction effect by the early shift-up driving was
examined, as the same time, NOx emission behavior was compared
between the driving with and without the early shift-up
driving.
As a result of the on-road driving test under the urban driving
condition, the early shift-up driving had a sufficient effect on
CO₂ reduction and fuel efficiency improvement. However, the early
shift-up driving caused an increase of NOx emission. This result is
largely concerned with the engine operating region, such as engine
speed and engine torque.