You are barking up the wrong tree!
Listen carefully!
This message is to those that drive diesel vehicles.
Diesel is at least 1.35 per litre.
New Cooking oil is 70p per litre (Rape seed or Corn oil as long as it is liquid at room temperature)
Diesels will run on cooking oil as long as you mix it with ordinary diesel. Half a tank of Diesel to Half a tank of Cooking Oil will work quite happily. Do not attempt to run your engine on 100% Cooking Oil. It will not start.
Cooking oil will clean your fuel system and may mean that you need to change your filter. Engines running on Cooking Oil will emit far less harmful products out of the exhaust pipe.
The government will try to charge you duty on the oil but it is not getting the message. The amount of duty in UK motor fuels is double that which our european neighbours charge.
I am not suggesting that any of your members do this but they are entitled to the information.
Sirius Dogstar