Will diesel engines cut your carbon footprint?

The New York auto show is starting up this weekend and an interesting thing are clean diesels.  The diesel engines, which will meet the emission standards, are 50 percent more efficient than the gasoline burning engine.  However, the cost of a clean diesel engine will be an additional 2,000 dollars.  

According to Csaba Csere, editor of Car and Driver “They are about as clean as a 50-state-legal gasoline engine.  But they are not capable of getting down to, say, ultra-clean SULEV emissions levels (a certification standard under California’s emissions regulations, which are the toughest to meet). They are, however about 20 percent cleaner when it comes to carbon dioxide emissions.”