Today's Working Lunch

I was interviewed about the car by Simon Gompertz of the BBC's Working Lunch program. The interview should appear on today's program - 12:30 on BBC2.

Smelling like lavender

When running on vegetable oil, the exhaust has a distinctive cooking smell.
It isn't that strong, and you can't smell it when you are driving along with the windows closed.
I personally think it smells much nicer than normal diesel fumes.
When using waste oil, it doesn't seem to smell like the food that was cooked - just a general frying smell. That might just be because the waste oil I use is fairly clean.

So I tried an experiment...
I took a couple of litres of vegetable oil and infused them for a few weeks using a large bunch of fresh lavender, from my friend's garden. I then filtered it (using a new filter element) and stuck it into my near-empty tank to see what effect it would have on the exhaust smell.
The answer, disappointingly, is that you can't smell the lavender on the exhaust.

I don't think I'll try any more smell experiments, but I'd welcome suggestions of other things to try - assuming they don't involve fossil fuels, and don't damage the car or the environment.