If you process the veg oil into pure biodiesel, which takes a fair bit of doing and a whole lump of gear, then run it through a heated fuel pump first, then you can comfortably run a biodiesel mix with standard diesel through most if not all diesel vehicles. Fact is that the diesel you buy on the forecourt can have a certain percentage of biodiesel in it anyway, so it is not entirely true to say that a Frontera cannot and should not ever run on at least a percentage of biodiesel.
The problem with chip fat (oil) is it requires considerable processing to get the lumps of fish and chip out first, then the water content, etc.,. You have to perform a titration to check the level of processing agents required before you "cook up" the biodiesel. Then the real killer for sensitive engines is the fact that the initial processed biodiesel diesel needs washing and drying for sensitive engines like the Frontera. Another problem is that biodiesel depending on the type of oil used gels at not so low temperatures ( around plus 5 deg C) as unlike forecourt diesel it lacks antifreezing additives, hence you up the mix of forecourt to bio in winter, and heat it through the heated fuel pump to a fair old temperature first.
Of course if you have the savvy to do all of the above, then it comes down to the start up and ongoing costs as to whether it is financially viable. Cheap processors on eBay (which do not do all of the above!) start at £600. The kit to do all of the above PROPERLY is around £2000 and upwards. Then the chemicals to process it are methanol and caustic soda to name but a few. These are not cheap either.
Then your chip fat supply? Chip shops get money for the used chip fat, because it does get recycled into commercial biodiesel, some of which can get mixed into your forecourt diesel, or sold on to farmers. So unless you do loads of miles and can get chip fat for pennies a litre so that you get a quick payback on your upfront investment, for the average man in the street you are stuck paying £1.43 a litre. Of course if you want to stick two fingers up at the tax man and derive enjoyment from your investment then that may be payback enough.
A WORD OF WARNING, METHANOL IS POISONOUS, IT GETS IN THROUGH THE SKIN AS WELL AS KILLS QUICKLY THROUGH INGESTION, NOT TO MENTION IF IT CATCHES FIRE IN YOUR GARDEN SHED BIO-STILL YOU WILL NEED A NEW SHED FOR A START OFF WHEN IT EXPLODES! THEN THERE IS THE CAUSTIC SODA, THAT BLINDS YOU IF YOU GET IT IN YOUR EYES, SO BEWARE IF YOU CONTEMPLATE MAKING YOUR OWN FUEL, IT COULD KILL YOU EASILY!! FINALLY OF COURSE IF YOU DO GET IT WRONG OR YOUR MIX ISN'T SUFFICIENT FOR THE OLD FRONTERA THEN YOU MIGHT NEED A NEW CAR TOO! YOU HAVE BEEN WARNED, SO DON'T BLAME ME!!!
Enough said.
Steve