I am surprised to hear the RAF use petrol generators
Glojo, when I joined in 1976, there was a good mix of petrol and diesel engined equipment. By the time I left in 1985, our ground equipment was almost entirely run on diesel engines. My memory is a little faded, but I seem to remember towing around 2 bowsers on Ascension to refuel the ground equipment so one must have been petrol, (there was no diesel, so 1/99 motor oil/avtur was an excellent substitute). The Regiment had their own ground equipment guys and from what I remember the screamer generators they used were petrol, but a lot of l4nd rov3rs were still had petrol engines so perhaps not such a big issue back then. I would think that now, the Armed Forces use diesel to fuel all their engine run equipment, with only a few exceptions. All the ground equipment I used since then, when working abroad, has been diesel engined.
One garage owner told me that in 2001 when Agfannystan kicked off, the rise in diesel prices was attributable to the sudden increase in demand from the military.