Modelling Result

Table 4.5 shows the example of one-day observation result from the PD vessel, whilst result from other vessels are provided in Appendix H. According to the observation results, time allocation for each activity including the average speed and total fuel consumption were plotted as illustrated in Figure 4.7. The figure shows that in the PD vessel, most of the fishing time is spent for locating the fish, followed by steaming, which refers to the voyage between the port and the main fishing ground. A large percentage on fish locating and steaming indicates that the vessel actively moves during the operation.

Table 4.5 Result of one-day observation in the PD vessel

Operation phase Duration (minutes) Main Engine Power Speed (knots) Start 05.30 am

Loading 00:15:42 off off 0.00

Manoeuvring 00:01:40 on 25% 1.51

Steaming 00:10:49 on 75% 6.26

Setting 00:05:13 on 50% 4.64

Hauling 00:17:03 off off 0.00

Steaming 02:05:00 on 75% 7.18

Setting 00:05:30 on 50% 5.56

Hauling 00:16:22 off off 0.00

Steaming 00:43:20 on 50% 5.35

neSetting 00:05:21 on 50% 4.97

Hauling 00:16:22 off off 0.00

Steaming 01:20:27 on 75% 6.05

Setting 00:05:19 on 50% 4.75

Hauling 00:16:10 off off 0.00

Steaming 01:24:08 on 75% 6.91

Anchoring/Break 00:45:58 off off 0.00

Steaming 03:54:20 on 75% 7.45

Manoeuvring 00:01:37 on 25% 1.67

Unloading 00:10:03 off off 0.00

Manoeuvring 00:01:51 on 25% 1.57

Finish 17.53 pm 12:22:15

The TN vessel can undertake active or passive methods. When performing active fishing, the TN vessel is mostly moving either steaming, fish hunting or encircling. In contrast, when a passive operation is conducted, the vessel only performs a return voyage to set and haul the net, as the net is left deployed at the fishing ground. In the LF vessel, the ferry also conducts return voyage between the port and platforms to shuttle the fishers, and it can be seen that the largest fishing time is spent in the LF platforms. Another small vessel movement is found in the HL vessel, as the fishing operation is conducted whilst the vessel is anchored.

Compared to other vessels, steaming time in the PD vessel is the largest percentage, showing that it goes to the farthest fishing ground. Furthermore, the figure shows that the TN vessel allocates significant time on hauling process, this is due to the difficulty to collect the entangled catch from the net one by one. The longest duration is found in the TN vessel with the passive method, which takes up to 27 hours due to the requirement to soak the net for at least 12 hours. Regarding the speed, the highest speed is found during

steaming in all vessel, as it is very common for skippers to run the vessels at high speed when heading back to the port.

Subsequently, data from on-board observation was used to calculate the constant k. As a result, fuel consumption for each vessel was modelled followed by SFC calculations, as seen in Figure 4.8 and Figure 4.9. The figures confirm that petrol engines consume more fuel than diesel engines.

Furthermore, when compared to the engine specification (Appendix C), there are slight differences to SFC estimated from this model, given the largest discrepancy is 10.5%, which is found in the PD vessel. Therefore, despite no SFC reference for the LF vessel being found, it is argued that this model can be used for further calculation.

Using information presented in Figure 4.7 and 4.8, fuel consumption for each fishing stage was estimated, which is presented in Table 4.6. For active operations, fuel is spent for steaming, fish locating and setting gear or encircling. Whilst for passive operations, fuel is primarily used for steaming. It should be noted that fuel consumption in the HL and LF vessels exclude fuel used for the generator as presented in the table.

Figure 4.9 Specific fuel consumption (g/kWh) of studied vessels

Table 4.6 Estimation of fuel consumption (litres) for each fishing stage

Note: *the vessel is anchored and the fuel is spent for generator

**the vessel returns to the port and the fuel is spent for generator in the 10 platforms

Fishing stage PD vessel TN vessel active TN vessel passive HL vessel LF vessel

Loading - - - - -

Manoeuvring 0.05 0.05 - - 0.18

Steaming 40.56 9.64 6.86 3.50 10.40

Fish locating 43.14 2.72 n/a n/a n/a

Setting the gear 1.25 0.35 -

Soaking the gear n/a - -

Hauling the gear - - -

Unloading - - - - -

Encircling 3.88 n/a

Shuttling 5.39

Towing 0.72

Boarding/Alighting 0.24

Total fuel (litres) 85 17 7 4 17

n/a n/a

n/a n/a

80** 3*

4.4 Summary

In this chapter, the fishing vessel operation has been described using profit and fuel consumption model. The purpose of the first modelling is to estimate the profit and its distribution amongst the stakeholders. It is developed based on the generic profit formulation using predefined input variables, which are constructed through statistical analysis, observation and interviews with the fishers. The model illustrates the fishing profit throughout the year, which is presented on a monthly basis for common, optimistic, and pessimistic scenarios.

The second model portrays time and speed allocation as well as fuel consumption throughout the fishing proses. Regarding time allocation, it is clearly seen that active and passive fishing operations show a significantly different pattern. In relation to speed, the vessels in both operations are typically run at high speed during the steaming. This model enables prediction of the fuel consumption at different fishing stage, and the result shows that steaming consumes a remarkable amount of fuel in all vessels.

In the next chapter, the profit model is used for calculating annual productivity, as the basis information for environment and economic impact assessment. Furthermore, the fuel consumption model is used for analysing possible measures in relation to fuel reduction, which will be further discussed in Chapter 6.

Chapter 5. Result of sustainability assessment of fishing vessels