I have a dedicated tank for heating, feeding a 15Kw oil fired boiler.
Living aboard last winter, I consumed about 100 Litres per month running the heating for two hours in the morning and four in the evening.
The system heats the boat (radiators) and 90 Litre unvented water cylinder.
I am able to buy red diesel for heating at 100% domestic so to run on white diesel will be a considerable increase in cost.
I could run on kerosene at approx. 70p per litre but I would have to factor in my cost for delivery.
It is all a bit "wait and see" at the moment.