Nice article here that describes Honda's new diesel exhaust treatment quite well:

http://www.leftlanenews.com/2006/09/...s-regulations/

Here's why this is an interesting step forward....

Gasoline vehicles have low NOx because they are able to use a catalytic converter, which reduces the NOx output by 99%.

Diesel engines currently can't do this because an ordinary catalytic converter only reduces NOx by about 10% when an engine is run in oxygen rich, lean conditions. Gasoline engines very rarely operate in these conditions, but diesel engines always do. This is why ordinary catalytic converters help clean up gasoline engine emissions so well but can't do much for diesel engine NOx emissions.

However the Honda system generates its own ammonia to reduce the NOx, and works under all conditions. Very clever indeed!

Expect to see it in US showrooms in three years time.

http://mysite.wanadoo-members.co.uk/ecotech/ecot.htm

This is impressive since the one previous alternative had been exhaust gas cooling and recirculation. By reducing the O(2) content, the combustion temperatures could be moderated yet still get the diesel high expansion ratio.

One of the reasons Toyota went with a hybrid design was to bypass the growing emissions challenges along with the fuel savings. The 13-to-1 expansion ratio gives some of the highest specific fuel efficiencies for any spark ignition engine.

Bob Wilson

Operation Iraqi Oil Freedom:

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Yes, leave it up to Honda to find elegantly simple solutions ... once again. It is so much like them.

As many have suggested, Honda's long term strategies for extreme fuel economy may hinge on this new Diesel development. I would definitely buy into it for sure.

Cheers;

MSantos