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The one expense on my farm that gives the highest returns from better management is not something simple such as protein licks, or something complex like staff training, or even intensive rotational grazing. It is diesel.
Diesel can account for up to 20% of a livestock farm’s budget, and this does not include damage from dirty diesel.
The following are the systems we use on the farm to reduce our diesel consumption, avoid dirty diesel, and increase our use of government assistance via the diesel refund system.
Police the litres
Saving on diesel starts with protecting it. As any farm manager knows, diesel is much easier to steal than sheep.
We keep our diesel tanks locked up in the barn and being the boss, I keep a vigilant eye on the electronic logbooks to quickly see when more than the usual amount of diesel is being used on the road.
Polish the diesel
Dirty diesel leads to mechanical expenses which is why our farm mechanic, Gert, routinely ‘polishes’ the diesel.
Polishing diesel boils down to killing the microbes and spores that live in the water droplets formed by condensation in any diesel tank. We use a wide spectrum additive to kill these diesel goggas and then drain the little bit of water that condenses twice a month.
To prevent sludge formed by dead bacteria from blocking the high-pressure fuel injectors in our Hilux bakkies, we also have filters on all our diesel nozzles and the main storage tank gets washed out every six months.
Test for paraffin
We also check the quality of any bulk diesel we buy. The profits that can be made by adding tax-free paraffin to diesel is a big and ongoing temptation in South Africa. It is also a very sophisticated industry. In January 2024, the Department of Mineral Resources and Energy said that 70 out of 1 000 fuel stations tested, were selling 50ppm diesel that was mostly paraffin.
We use a reusable diesel test kit from a local diesel injection servicing company. The kit is a 500mℓ bottle containing a floating polymer disk. If the diesel sample contains more than the allowed 5% paraffin, the pellet sinks and with that the engine warranty, should you put that paraffin diesel into your bakkie or tractor.
Toyota’s warranty warning
While it is possible to drive a new bakkie on diesel diluted with cheap paraffin, especially in places where only dirty diesel is available, Toyota’s advice is: “Don’t”. The first thing manufacturers check in case of an engine warranty claim is the diesel quality in the engine. If it has more than 5% paraffin, all manufacturers will void the engine warranty on the spot.
As Toyota explained in a media statement, paraffin ignites at lower temperatures than diesel; is not as effective a lubricant; and does not contain any of the additives required to clean moving parts in the injectors, or protect the seals.
So, while you can drive a modern diesel engine on dirty diesel for a bit, repeated combustion of paraffin will lead to catastrophic diesel engine failure, with no warranty cover.
Read more about Factory settings last, remaps don’t.
Finally, fill in the forms
Doing the paperwork to claim the diesel rebate is where Mbali, our real Zulu princess and farm administrator, works hardest to earn her keep.
This process starts with registering for VAT, then collecting data from the electronic logbooks on all our diesel vehicles, and ends with me sending in the VAT 201 form to claim the rebate, which is basically a discount on our VAT payments.
This discount amounts to 366c/ℓ on 80% of our diesel costs. By comparison, ship owners that service fibre optic cables along Southern Africa’s coastline get a rebate of 588c/ℓ, while owners of diesel generators in plants larger than 200 megawatts get 403c/ℓ. – Alwyn Viljoen
