In answer to the OP question, in the winter, the most I run is 30litres of Veg, to filled up tank of Diesel, which is normally about 40liters, but then in the summer, the most I run is 40litres of Veg to about 30litres of Diesel. Having said that, I have not yet had a really cold winter to worry about.
been running years and in summer i use 90 wvo with 10 derv,then as it gets colder 75 wvo then i put in a jerry can at pump 13derv and 5rug mixed then that goes into my ready to use wvo.sometimes a little 2 stroke oil as well plus acetone to make a better injector pattern and a bit of cetone booster as rug lowers the omph of the wvo.the last 2 0.01%.this works for me.
all mixed fuel is made as i need it run through my filters so no surprises when i get a cold snap. the fuel i use,well a pop bottle full is always left out in the open so i can see what it is doing and make any adjustments.
i only ever top out the tank at the time i do a long run so if i need to i can put in a derv rug mix when it goes - for a few days.
Just out of interest, and not wanting to sound like I am an "Anti", as I use Veg oil myself, but I struggle and can not get my head around how making usable fuel from waste veg oil at home can be cost effective, unless you have a ready supply of free veg waste oil on tap, and even then, with the amount of work and additives it takes, I am still struggling with the idea.
As I see it, bearing in mind, it's only from what I had read on line, assuming you process your own WVO, once you have added up the electricity to clean it, filter costs, purchase and transport of raw materials, then purchased and added all these extra bits, plus having to dispose of all the waste stuff that does not convert, does it really work out any cheaper than just going to the garage, and filling up with straight DERV oil? I read somewhere that about a 5th of the raw product remains as waste product, so you only actually get 4litres out of every 5 you buy.
I was looking the other day, and someone was selling a WVO set up, and it was £1500 for the kit, plus there was a load of used Veg oil that worked out at 50p/litre before it had been cleaned. Basically it was £2k, for it all. Based on that price, and not allowing for any of the consumables, and extra chemicals, I would need to produce 10,000 litres of WVO, just for the kit to pay for it's self. That's a minimum of 4 years before I can even think of seeing a return on the kit.
I only pay 65p/litre for unused veg oil from Costco, and I can put that in without doing anything.
