Re NOX emissions, there is a lot of development work going on in this area. Pre-production road locomotives with significantly reduced emissions are already out there, and hybrid road engines are under development. Here's a recent GE "Evolution" engine that meets the latest EPA standards.
Oooh - the pot calling the (steam) kettle black! That's the trick the diesel promotors played on steam so often in the Forties and Fifties when the boot was on the other foot, except that they often compared really old-fashioned steam with the very latest latest diesels.
Where Waller is concerned your criticism is invalid as, rather than directly compare with a slightly older diesel he made a point of asking for the latest specifications the diesel manufacturers could offer. However I have always thought that the trials and comparison should have been pursued after 1992 taking into account the effects of wear and tear in service. Personally, I would like to see an independent body set up - a sort of international "Porta Institute" to look into that sort of question. We can dream!
The GE diesel looks interesting, I'll follow that up. John of Paris
