Doubtless you know of catalytic converters, which are cheap enough but with diesel trucks you should also consider soot filters which are a cost multiple of cat converters, because of the health risk from particulates. But even then they are not entirely squeeky clean. When your trucks finally need replacing, and you still wish to remain with ic trucks, you may wish to consider CNG until something better, like hydrogen power, comes along. The great advantage of CNG over LPG is that they are much cleaner, in that they do not emit benzene, a known carcinogen. That said, there are downsides to CNG in terms of performance and other issues.

It is a pity that the green movement has taken the moral high ground over carbon emissions, based on inadequate scientific data or "bad science". We all want to see a cleaner planet but the problem is how to go about the right way to achieve that. Making pronouncements which translate into global action based on skimpy data is downright dangerous and irresponsible.

A good example is the Green movement's greatest "victory" over the bannng of CFCs, back in 1987, used mainly in refrigeration and air conditoning. It know emerges that CFCs' replacement, HFCs (hyrodflourocarbons) is far more potent, ton for ton, than carbon emissions at fouling up the atmosphere.

One ton of HFC-23 has the same global warming potential as 14,800 tons of carbon dioxide. Just how bad that news is, especially for Britons living on the west coast, you may wish to discover by going into Google and tapping in: Marine low emission zones promise longer lives.