Conclusion

This report has examined the potential of tidal stream energy extraction for eight different sites at multiple angles. The speed of the tidal stream at muara Batang Lupar meets the 1.5m/s minimum requirement used to justify if further investigation against the potential of generating power by extracting tidal stream energy is deserving.

Not to dismiss the possibility of exploring tidal energy in Sarawak but it is important for the authorities or parties from the private sector to realize that the development of a tidal plant involves a good budget and a detailed study of the potential of the targeted site. Components of such detailed study are but not limited to environmental restrictions, available power generation, grid interconnection availability, transmission distance, constructability, maintenance cost, and conflicts with other users of the sea space and exposure to storm waves or other risk factors.

If the interest is for real, it is recommended that developers from the UK are to be engaged and to perform a good evaluation on Batang Lupar and its potential. Harnessing tidal energy is wise due to the sustainability and good predictability of the energy. It will be good for the authorities to tap into this energy the soonest possible. Table 3.20 summarizes all.

Sites / Criteria

 Coordinates

Meeting the 1.5m/s minimum speed requiement

Meeting the clearance requirement for oceangoing vessels

Meeting the clearance requirement for shallow draft vessels

Potential Tidal Stream Energy Extraction Site?

Off Kuala Igan

01° 48’ 00” N
110° 33’ 00” E

No

Yes

Yes

No

Off Kuala
Rajang

02° 30’ 34” N
111° 08’ 41” E

No

No

No

No

Off Tanjung Po

02° 07’ 32” N
111° 01’ 37” E

No

No

No

No

 

Off Kuala Paloh

02° 55’ 00” N
111° 30’ 00” E

No

No

No

No

 

Off Tanjung Sirik

03° 37’ 00” N
111° 45’ 00” E

No

No

No

No

 

Off Kuala Miri

03° 15’ 46” N
113° 00’ 04” E

No

No

No

No

Bintulu Port

 

04° 23’ 52” N
113° 57’ 54” E

No

No

No

No

 

Pulau Triso (Batang Lupar)

01° 30’ 45” N
110° 57’ 55” E

Yes

No

Yes

Yes

 

RECOMMENDATIONS

One thing unique about tidal stream energy is the predictability itself. The idea should not be hard to grasp because tidal activities are essentially the product of the orientation of earth, moon and sun, in which the knowledge behind has long reached its maturity. If a suitable site has proven to be suitable for the extraction of tidal stream energy, we can be rest assured that the supply of electricity will always be there, though the amount of electricity supplied may be hard to ascertain due to the variable behaviour of it. This characteristic of tidal stream energy is itself a distinct advantage over wind and hydro energy.

To understand the potential of tidal stream energy along the coastline of Sarawak in a more thorough manner, a comprehensive inventory of tidal stream data, particularly areas with narrow passes along the shoreline is needed. The process of gathering such information stretches over a relatively long period of time and involves an extensive amount of resource. However, if a sustainable and green energy is what we are looking for; tidal stream energy is one not to be left out.

Even though the notion of having sustainable and green energy may sound decent but judging by the amount of resource involved, it will be good to begin the search for tidal stream energy systematically. The result presented earlier shows a relative consistency of the speed of tidal stream at the North West region of areas offshore of Sarawak, stronger than those found at the North East region (Bintulu and Miri). The continuing study of sites with potentially high tidal stream energy should therefore be concentrated off the coast of the Southern (Kuching) region and Middle (Sibu/Mukah) region of Sarawak, as indicated in Figure 3.21.

The potential of tidal stream energy extraction off the coast of Sarawak could be understood better with more and more areas being investigated apart from the seven sites examined under the scope of this report. The speeds of tidal streams at those areas must be acquired no matter how, regardless of the methods proposed, as long as the readings obtained possess the capacity to be used to tell and predict the behaviour of tidal stream at that particular area.

It is ought to be understood that tidal current energy is in a great deal referring to energy captured from the effects of tidal activities. The energy captured from non-tidal current will be associated to tidal energy, unless the flow of current is in a great deal dominated by the phenomenon of tide.

Koh et al [9] in an attempt to assess the potential of harnessing tidal streams for electricity generation in Malaysia has identified three locations with great potential for tidal stream energy extraction. Among the three,one of them is located in Sarawak. In contrast to this report, Sibu is regarded as a potential site for tidal stream energy extraction. An energy output of 386 GWh/year is deemed feasible by taking into considerations certain assumptions inclusive of the power coefficient of 0.4 and the minimum operating speed of tidal stream of 1.1m/s.

Regardless of the assumptions made, the decisive factor that has contributed to the conclusion is again the speed of the tidal stream. While a minimum speed of 1.5m/s is used in this report to determine if the extraction of tidal stream energy is economical, a speed of 1.0m/s is likewise used by Koh et al as a determining factor. Such observation that the speed of the tidal stream in Sibu in general (coordinates were not mentioned) is greater than 1.0 m/s is different from the data published by the Director of Marine Department as in year 2006. The fastest tidal stream throughout the year was mere a 0.36m/s. The data published by the Director of Marine Department were however predictions made on some actual readings taken years ago. On top of that, the exact location of where the 1.0m/s is cited may also be different from the location where the 0.36m/s is predicted.

Both Koh's and this report is in general agreement that if tidal turbines are to be deployed for the extraction of energy, coastal areas from off Kuching to off Sibu have obvious advantage over areas from off Sibu to off Miri. Apart from that, both reports agree that tidal energy is a green energy worth exploring. Although it is apparent from the raw data obtained from Jabatan Laut Sarawak (JLS) that none of the seven locations investigated in this report shows good potential for tidal stream energy extraction, as the technology evolves and as devices that are capable of extracting energy from slow moving tidal streams emerge, we will see a major transformation of the methods of generating power in this region for sure.

Figure 3.21: Regions where the consecutive studies of tidal stream energy should be centred.