I am from Canada and it is very common to see taxi fleets, police vehicles and company fleets in general running on propane and natural gas. I know this is not bio, but the thrust to alternate fuels is there.
There was a try at a 10% corn based methane fuel a few years ago, but my Volvo had a horrible knock with it.
I have written Shell asking them if they have any info on the product.
The exhaust, by the way is not as strong a smell as normal diesel.

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Bob Morrison
92 300D 2.5 -197000 Miles
87 300D-170000 Miles The Californian
87 Volvo240DL-200000+MilesGrandson's Now