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Figure 3.10 Haulout and harvester fuel use (Sandell and Agnew 2002)
Mallee System
As a proven system robust enough to harvest mallee has not yet been developed the exact
configuration of haulout vehicle is not known. Hence, the actual cost of the infield transport
component is unknown.
However, McCormack et al. (2009) in their model investigated the effect of haulout travel speed,
transport distance and bin size on haulage costs.
Figure 3.11 shows the influence of bin size and haulout speed upon the cost of infield transport, with
costs ranging from $6 to $12 per green tonne. The cost is equally sensitive to both variables.
Figure 3.12 shows the influence of infield transport distance upon cost, and compares this with the
effect of pour rate. Estimates range from $5 to $12 per green tonne, and pour rate is much more
influential upon the cost of infield transport than distance, because even at short transport distances,
the harvesting system still requires two haulouts. Fuel, repairs and maintenance vary with the amount
of work done per shift, but other costs are either effectively fixed on a daily or shift basis or fixed
annual costs.
Fuel use estimates for infield transport vary from 0.9 l/gt to 1.9 l/gt according to the assumptions
about transport speed, distance and payload. These values are very sensitive to the details of
operation, such as the proportion of time the haulouts spend under load at the rated engine speed, but
it would be reasonable to assume that with longer transport distances, fuel use would be higher than
the observed values in sugarcane. There is some potential for relatively good efficiency if the larger
payloads lead to a better vehicle load to gross mass ratio with large mallee haulouts.
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