Quote:
Originally Posted by chunder
Seems diesels are not quite as clean as poeple thought or governments, nicely done makers for getting fleets and the government on your side, managing to get UK supliers to make diesel dearer and now apparently puling the wool over peoples eyes as to how clean diesels are in terms of ar pollution!
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Its not as simple as that though is it.
There are two big differences between petrol and deisel emissions, CO2 and carbon particulates. A decade or two ago the fact that diesel cars emitted substantially lower CO2 was considered far more important than their higher particulate emissions, hence better for the environment and encouraged by governments. In the intervening years two things have changed. Petrol cars have got more efficient which means there is less CO2 advantage for diesel, and the health implications of carbon particulates from diesel have become better understood (it's nasty!). This is why the balance has shifted, especially for urban areas where there are lots of cars.
Particulates are essentially a local issue you emit them and people breathe them in the immediate area, they don't persist in the environment or travel far as rain scrubs them out of the air. CO2 of course is a long term addition to the global atmosphere and screws the climate for the whole planet. Perhaps which you choose depends if you are more worried about poisoning your neighbours or wrecking the climage for your children and grand children
I know NOX tends to be worse from diesel too but I'm not aware that it has been driving the changed perception, I could be wrong though.