Anybody know anything about it, where to get it or even if it is available in the UK? Are any mods required to the engine?
I ask as Kahn have sponsored a Biodiesel fueled RRTD6 Vogue with Kahn trimmings in the Gumball3000 this year and I am intrigued! There is a note in the front of my current RR's owners' manual to the effect that the use of it will invalidate the warranty.......

It's the same in the Netherlands : RRS TDV6 - no warrenty if you are using Biodiesel !!!

From what I can gather, biodiesel is simply normal diesel with a small (circa 5%) bio content (ie fuel derived from harvested organic material). Our local police force announced that they were going to use it in their vehicles, although it does seem a bit of a token gesture (especially when their highway patrol cars seem to be Volvo t5's - which are petrol).