By Tia Ghose
The news just keeps getting worse for Volkswagen.
The company may have to recall up to 500,000 diesel cars in the United States and 11 million vehicles worldwide because they emit up to 40 times the allowable levels of air pollutants that are called nitrogen oxides (NOx), The company is now embroiled in a scandal after it was revealed that Volkswagen deliberately turned off the filter designed to trap NOx from the exhaust.
But the recall has also raised this question: Was it so hard to make diesel cars run with low emissions that the company had to resort to cheating?
It turns out that diesel engines have an inherent trade-off between power, fuel efficiency and clean emissions, experts said.
“You have power, you have energy, you have emissions: You get to choose two of them,” said Don Hillebrand, the director of energy systems research at Argonne National Laboratory in Illinois, and the former president of the Society for Automotive Engineers…
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