The interesting thing about NOx and soot pollution is that it remains a local problem, unlike the (higher) CO2 emissions from gas engines, which are just a contribution to global climate change. In that sense, I'd say it would almost be preferable to require all passenger vehicles be diesel - people could see quickly why they should drive less... Many diesel owners in the US (myself included) run varying amounts of biodiesel in their engines, which produce slightly more NOx (generally), but less particulates.
Reducing NOx emissions would be great, odd they don't mention particulates, since they seem to me to be one of the worse aspects of diesel engines[1] (and I'd expect that burning 90% less diesel should mean a similar drop in particulates).
What I find ironic is the Diesel emission cheating has allowed NOx pollution to skyrocket in Europe which causes terrible localized air pollution but lowers their CO2 emissions (vs using Gasoline engines) and lowers their crude oil import needs. So companies that promote Diesel Engines can claim to be lowering CO2 emissions at the cost of very polluting NOx emissions.
I seem to not have communicated my point very clearly.
Diesel particulate pollution kills very significant numbers of people, and it kills poor people (who have to live next to the freeway and on urban thoroughfares) disproportionately. I don't care about how easy it is to find a $100 car; I care about policies that we can enact today that can stop truck owners and manufacturers from externalizing their pollution costs onto everyone else. You make a good point about PM being easier to address than NOx - PM is more of an urgent concern given what we now know about its health effects. Whether by retrofitting or by retiring, the engines that emit more PM than the 2008 standards have to go.
New diesels are fine. I agree with you EV trucks are not here yet. The point is there are trucks out there that are 10,000x more harmful in PM emissions than the same exact capability new truck. They need to be removed.
Don’t feel bad. Each and every technology has its failures which will bite at some point. I expect that in a few years, e.g. the recyclability or toxicity of batteries in electric vehicles will hit headlines.
This NOx emission thing is more a PR disaster than an actual environmental problem. The VW diesel engines are still remarkably efficient and nice pieces of technology, at least if you compare them to the huge gasoline engines that they often replace.
(FWIW, I drive a diesel but not made by VAG (this is Renault). It’s probably worse than any current VW engines, but because it’s a few years older, no one complains. It passes the local MOT tests with flying colours, and I get around 5.6 l/100 km or 42 mpg for a minivan which I think is nice enough).
Reducing NOx is one a fine and noble effort, but there's not much new in this BOSCH corporate press release. However, there are plenty of technologies for reducing diesel engine NOx (1), including Selective Catalytic Reducers (SCR's), Exhaust Gas Recirculaters (EGR), and even injecting water into atomized diesel.
Further, reducing NOx is one thing, but you still have other harmful emissions notably SOx and black carbon. So to Dr Volkmar Denner, CEO of Bosch, who says: “There’s a future for diesel. Today, we want to put a stop, once and for all, to the debate about the demise of diesel technology." I respectfully argue that until you can make Diesel as clean as H2 fuel cell, the push to eliminate diesel burning engines will go on.
For my money, the best environmentally sustainable 'fuel' is electric via Hydrogen/Air powered fuel cell, in which the hydrogen is generated by electrolysis powered by renewable generators (wind, solar, hydro). We've seen a significant push in the Maritime sector towards conversions of diesel engines to LNG-fueled engines. However, LNG (which may have significant methane slip - a really BAD greenhouse gas - if you're not careful) isn't nearly as clean as H2.
diesel might be a bit more efficient, but produces more nitrogen dioxide (and other oxides) which are harmful to humans and the environment, which is why they are being banned in some parts of europe.
You should really mention that it's diesel in a comparison like this. Diesels produce significantly more air pollution (particulary nasties like NOx) than similar gas/petrol engines.
Though you appear to have some vested interest in the proliferation of Diesel engines.
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