In the automotive sector, BMW performs best in emission testing. Honda and Volvo frequently pass these tests more consistently than other manufacturers, albeit not without some variability. At the bottom of the list are Hyundai, Mitsubishi, Chrysler, and GM.
Researchers arrived at these results after analyzing data from nearly 4 million cars and trucks that underwent government emissions tests in Illinois, Maryland, and Massachusetts (USA).
The study indicates that a vehicle’s design significantly influences its environmental pollution potential.
In the truck category, Honda, Toyota, and Nissan lead the performance rankings. Ford is cautiously in fourth place. Chrysler and Mitsubishi frequently fall to the bottom of the list.
“There are several factors that determine the pollution levels of trucks and cars, and the manufacturer is the most significant of these,” said Jean-Michel Guldmann, a co-author of the study from Ohio State University. “Some manufacturers produce cleaner vehicles than others.”
Researchers also identified the following trends:
- Poorly maintained vehicles are more likely to “fail testing.”
- Improving fuel efficiency in both cars and trucks helps reduce emissions.
- The longer a vehicle is driven, the higher the emission rates.
- Older vehicles are more prone to failing tests due to higher rates of equipment and engine wear, leading to increased emissions.
- On average, cars emit fewer pollutants in spring and summer, possibly due to changing atmospheric conditions and variations in fuel composition from refineries.
Vehicle age is also a significant factor in determining emission levels. On average, a car manufactured in 1985 releases CO at a rate 38 times higher than a model produced in 2001. Toyota shows the least difference between new and old models, as even its older vehicles are relatively low in emissions. Other manufacturers like Honda, Nissan, and Hyundai exhibit significant disparities between generations, with older models producing far more emissions.
T. An (according to LiveScience)
