Re:Volkswagen and the Blame the Engineer Game
by _jp__ on Friday December 11, 2015 @11:57AM
(#10718165)
Thanks for your explanation. But i think the problem here is not the strategy. We are talking about individual car performance. This is not about the NOx produced by the whole VW cars. Every other single manufacturer car is at least 4000% better ? Incredible. This is the question.
Re:Volkswagen and the Blame the Engineer Game
by masklinn on Friday December 11, 2015 @01:03PM
(#10718676)
> But i think the problem here is not the strategy.
The problem is the strategy.
> We are talking about individual car performance. This is not about the NOx produced by the whole VW cars.
We are talking about the NOx emissions of diesel engines in general, and of VW's decision to base their US and global strategy around diesel.
> Every other single manufacturer car is at least 4000% better ? Incredible. This is the question.
What's the point of praising my comment if you didn't fucking read it? Other manufacturers don't have 4000% better cars, in the US other manufacturers sell gasoline cars which intrinsically produce significantly less NOx.
The US has very, very stringent NOx regulations, much more so than Europe (VW's cheating was in fact discovered through european clean diesel advocates pushing for tighter US-style regulations): EPA Tier 2 / Bin 5 has a 0.043g/km limit whereas EURO5 is 0.18g/km and the new (2014) EURO6 standard lowers that to 0.08g/km (still twice EPA)[0].
Diesel has plenty of advantages but is a big producer of NOx (compared to gasoline) because NOx is formed at high pressures and temperatures, and gasoline engines have much, much lower pressure and temperatures than diesel[1]. Also importantly, increasing diesel engine efficiency runs them hotter, which increases NOx production.
VW bet on a all-diesel strategy worldwide, and that included a "clean diesel" push in the US.
[0] for what it's worth, VW engines don't pass EURO5 either (in fact they don't even pass EURO3, the first EURO standard including NOx) which is why they're also in the shit EU-side, just to a way lower extent than in the US (their engines exceed EURO5 limits by a single-digit factor versus double-digit for EPA limits)
[1] EURO standards reflect this (though whether they should is debatable), EURO5 has a 0.18g/km NOx limit on diesel engines but 0.060 on gasoline