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Table 7.2 Scenario two capital equipment<br />

Equipment description<br />

capital<br />

value<br />

salvage<br />

value<br />

equity<br />

anticipated<br />

use<br />

$ $ % hours<br />

mallee harvester 750,000 10,000 0 10,000<br />

200 hp tractor 213,800 81,800 0 10,000<br />

200 hp tractor 213,800 81,800 0 10,000<br />

shed 150,000 0 0 50,000<br />

service vehicle + fuel trailer 50,000 5,000 0 10,000<br />

25 tonne side tip haul out 45,000 11,250 0 10,000<br />

25 tonne side tip haul out 45,000 11,250 0 10,000<br />

Scenario Three: Side-tip trailers<br />

Scenario three represents a high-efficiency high cost system that utilises modified 40-feet shipping<br />

containers and swing-lift or side-lift trailers. These 25 tonne capacity road-haul trailers are taken into<br />

the field and are filled directly from the harvester. These bins, represented in figure 7.3, are hauled in<br />

field behind a tractor and, once full, are hauled to and uncoupled at the nearest trafficable road. It is<br />

assumed that the uncoupling would take fifteen minutes.<br />

The containers are modified so that they unload from the side and the ro<strong>of</strong> is open for loading. The<br />

container pins on one side <strong>of</strong> the trailer are modified so that they can pivot. The advantage <strong>of</strong> this<br />

system is unloading time at the factory: the swing-lift is attached to only one side <strong>of</strong> the container, the<br />

side chute on the container is opened and the whole container pivots and unloads at the side.<br />

Unloading times for this system would be in the order <strong>of</strong> fifteen minutes. End-tip trailers, which need<br />

to be uncoupled for unloading and then re-coupled, have unload times in the order <strong>of</strong> one hour.<br />

The road transport component already accounts for rear-tip trailers valued at $86 350 each. Thus the<br />

additional value <strong>of</strong> the swing-lift trailers, $89 650, is accounted for in the haul sector, plus the full<br />

value <strong>of</strong> two additional trailers. The total system cost is $1,948,900 and is detailed in Table 7.3<br />

7.3.3 Other Operating Assumptions<br />

Elevator pour rate represents the tonnes <strong>of</strong> product flowing from the machine while it is continuously<br />

cutting. A target elevator pour rate <strong>of</strong> thirty tonnes per hour was used in all scenarios. However, this<br />

was varied in one sensitivity analysis using 10, 30, 50 and 70 tonnes per hour. These correspond, at<br />

the assumed plant yield <strong>of</strong> one 50kg tree every 2 metres, to ground speeds <strong>of</strong> 0.4, 1.2, 2.0 and 2.8<br />

km/h respectively. Harvester cutting speed is assumed to be limited to 3 km/h.<br />

Time to turn from one belt into another is estimated using the belt spacing and a tractor acceleration<br />

<strong>of</strong> 0.01 m/s 2 and a maximum ground speed <strong>of</strong> 25 km/h. Harvesting is assumed to occur in a circuit<br />

pattern.<br />

It is assumed that two haulouts <strong>of</strong> twenty-five tonnes capacity are used in all scenarios.<br />

Fuel Burn rates, in litres per hour, are included in Figure 7.4. Fuel is costed at $1.40 per litre, which<br />

is exclusive <strong>of</strong> on-road tax.<br />

162

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