Diesel Cost per Tonne: Your Haul Fleet Has a Drinking Problem

Your haul fleet has a drinking problem. That is normal; it is a haul fleet. The real question is whether some trucks are drinking more than their share, and whether anyone would notice before month-end.

On an open-pit mine, diesel is one of the largest operating costs, and every litre also carries the carbon fuel levy. Yet in many operations fuel is reported as a monthly total: litres issued and rand spent. That tells you what you spent. It does not tell you where, why, or whether it was reasonable for the work done.

Totals are very good at keeping secrets

A monthly total rises and falls with production, haul distances and the weather, so a good month and a bad month can look identical. The useful question is efficiency: how many litres did it take to move a tonne, and how does that compare across pits, fleets, shifts and operators?

Building the KPI

Good news: most of the data already exists.

• Fuel issues per vehicle from the fuel management system.
• Loads, cycle times and idle time from the fleet management or dispatch system.
• Tonnes moved from production reporting.

Join these by vehicle and shift and you get litres per tonne moved, then diesel cost per tonne and carbon per tonne. The first version does not need to be perfect. Even a weekly view is a big step up from one number a month.

Where the savings usually hide

• Idle time: engines running while trucks queue at the shovel or the crusher, burning fuel to go precisely nowhere.
• Outlier units: trucks that consistently burn more per tonne than the rest of the fleet, often a maintenance issue in disguise.
• Haul routes and road condition: longer or rougher roads show up clearly once fuel is measured per tonne.
• Operator practices, best addressed through coaching rather than blame.

Put it where people will see it

A KPI only changes behaviour if the right people see it at the right time. Put litres per tonne in the daily production meeting, by fleet and shift, with a simple trend. The gap between your best and worst units is usually the quickest saving on site. Your fleet won’t thank you, but your budget will.

Want to see where this applies in your operation? Our free guide covers diesel, energy and carbon tax in more detail. Or request a call with our team.