Interesting, Brian. Here is a general PDF on the Clean Sky initiative:
http://www.cleansky.eu/upload/downlo...aWestland).pdf
Actually diesels are overdue a revolution in combustion technology, which will reduce how much the weight nibbles into payload. The improved fuel economy helps because it reduces fuel load. As for soot, see tier 4 ground vehicle requirements, where the latest oxidation catalysts and common rail injectors have reduced this to a historical footnote.
I'll keep an eye on this story.
