Now you are really struggling, refrigeration plants!As I see things, just because they are not the largest part of the problem doesn't seem to make them not a problem. I assume when you say they are not a problem, that includes the things like refrigeration units which often also run on diesel and produce their contributions?
Of course all i.c. vehicles are a problem, but that isn't what I'm posting about. I'm posting about the most effective solution, and that is emphatically dealing with the vast number of cars, compared to the relatively very small number of large trucks.
To once again repeat, the serious pollution hotspots affecting people the most are in cities where the great majority of the people and their cars live. Conversely the great majority of the distribution truck mileage is far outside of the cities and towns where their polution is dispersed and naturally cleansed.
It's clear you are desperately struggling to put all the blame on trucks and avoid any action against cars. It won't work, the authorities aren't daft and will continue to act where it's not only most effective but also easiest to achieve.
Just consider how difficult it is to deal with truck pollution and the tiny gains when you do since there's so few trucks comparatively and so little of their pollution is in urban areas.
Then consider how easy it is to deal with car pollution due to the variety of solutions. First solution which is happening now is getting back to petrol engines, diesel sales now slumped. Then there's hybrids reducing consumption. Then there's PHEVs which for many people are enabling them to do most of their trips, which are short, on electric drive only. Then there's fully electric cars with sales constantly increasing as they've become more capable. Then there's the city car share schemes, we have some in London. Then there's public transport, which in London has been growing continuously for the decade or so, the bus fleet doubled, a tram system installed and expanding and a new Crossrail underground railway.
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