electric power grid optimization for the state ...97-113).pdfthe electric power decisions made in...

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Int. J. Elec&Electr.Eng&Telecoms. 2014 Prashobh Karunakaran, 2014

ELECTRIC POWER GRID OPTIMIZATION FOR THESTATE OF SARAWAK AS AN EXAMPLE FOR

DEVELOPING COUNTRIES

Prashobh Karunakaran1*

*Corresponding Author: Prashobh Karunakaran,[email protected]

The current worth of the power industry worldwide pegged at six trillion dollars. The cost ofpower plants are so high that only politicians of the highest level can make decisions on whichto choose. The problem is that there are few engineers in the very top levels of politics worldwideand this is especially so in the developing countries. Incorrect political decisions with regard tofacilities within the power grid can cause sufferings to the people of developing countries asdebt creeps into their lives. This paper therefore aims to be a guide for politicians in developingcountries to wisely choose the appropriate power plants unbiasedly. This is done by depictingthe electric power decisions made in the state of Sarawak, Malaysia as well as of designs tofurther improve this grid. Sarawak has used some of the best minds in the world to develop alarge and exemplary grid. Currently politicians in developing countries tend to get consultantsfrom major corporations aboard. Every activity of large corporations must lead to maximumprofit for themselves, often to detriment of the host developing country.

Keywords: Electric power grid optimization, Political decision making, Developing countries

INTRODUCTIONEngineers have tended to stay away frompolitics in both developing and developedcountries. This problem was highlighted bymany top thinkers and this cannot carry on ashigh technology becomes increasinglyindispensable in developing countries.Experienced engineers need to be at thehighest decision making levels of countries.

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Int. J. Elec&Electr.Eng&Telecoms. 2014

1 Universiti Malaysia Sarawak (UNIMAS, Kota Semarahan, 94300, Kota Samarahan, Sarawak.

This sphere is currently the realm of lawyers.In some countries like China, top engineersare just picked to be politicians but in ademocracy engineers have to be cajoled tobecome politicians for the benefit of society(Duderstadt and James Derstadt, 2008).

In this work, the power system ofSarawak, Malaysia was studied and designswere formulated to optimize it further as a

Research Paper

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reference model for other developingcountries.

Sarawak is the largest state of Malaysia (at124,450 km²) but with a population of only 2.5million. Sarawak is located on the equator andtherefore has a rainfall of about 4000 mm (157inches) per year. This compares to a USAaverage of 715 mm (28 inches). Thetopography is also of high mountain ranges atthe border with Indonesia. This four factors oflarge land area, low population density, highrainfall and mountains ranges makes it idealfor hydroelectricity production. It is for thisreason that Sarawak has already built threedams with two fully running and nine more inthe planning stage. The sites of these damsare depicted in Figure 1.

Sarawak’s hydroelectricity resources wereconfirmed the SAMA Consortium, under atechnical aid to Malaysia granted by the

German government via the German Agencyfor Technical Co-operation (GTZ). A total 155dam sites were identified, each with a potentialto generate more than 50 MW. This gives acapacity of approximately 80,000 MW.Sarawak needs to tap to this resourcebecause it is her advantage.

However many of the dam sites are locatedtoo close to each other such that thedevelopment of one site will flood some others.Therefore only 51 of the 155 dam sites can bedeveloped. Their combined hydroelectricgeneration potential is 20,000 MW (the currentusage for Sarawak is 1,695 MW). Figure 2shows the current grid system in Sarawak tocarry the power from the power stations to theconsumers.

In 2013, the amount of CO2 emitted to theatmosphere was the highest in earth’s history.The figure was 36 billion tons. As this keeps

Figure 1: The 12 New Dams Sites in Sarawak

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up we will have more disasters like Sandy andthe Japan tsunami. A scientist from U.N warnedthat a two degree rise in earth’s temperaturewill trigger floods, droughts and storms(Garside Ben and Baird Jane, 2014). Humanbeings inevitably need industrial production,the choice for humans is use highly pollutingcoal fired plants or clean energy likehydroelectricity, wind or solar. If Sarawak fullyutilizes all her hydroelectric potential, many ofthe heavy industries planned for constructionin China can be moved to Sarawak thus takingout the huge increase of CO2 emission fromcoal fired power stations of China. Industrialproduction needs lots of cheap energy, Japanenabled her huge spurt of industrial productionafter World War II (WWII) because of the largeutilization of nuclear energy. The introductionof nuclear power in Japan after WWII wasencouraged by USA in the hope that it will deterJapan from going into another war to secureresources. Nuclear power gave Japan cheapelectricity to kick off her huge industrializationprogram (Jha Saurav, 2010). India hopes toget the same spurt with thorium based nuclearenergy because of the abundance of thoriumin India (Adee Sally, 2010). In fact Japan wentthrough a phase of eliminating the dependenceon nuclear power after the Fukushima disasterin March 2011, but has recently (2014)decided to embrace fully nuclear energybecause this short experimentation withhydrocarbon energy was just too expensiveand resulted is too much pollution. Besides theprofessor emeritus, Kiyoshi Kurokawa fromthe University of Tokyo concluded from thereport of the Fukushima disaster investigationteam, that it was not the tsunami but the laxsafety protocol in the construction of the plantthat caused the disaster (Orcutt Mike, 2014).

TECHNICAL CONTENTIn Sarawak the construction of the 13 damsplanned or already built have a main purposeof powering the heavy industries near Bintuluwhich is gradually becoming the load centerfor Sarawak. The current load center is in thelargest city and capital, Kuching.

Other renewables like wind and solar weretried out but failed to proof feasible. Solarpower in Sarawak is a problem becausethough there is sunlight, it is quite often blockedby the heavy cloud cover, typical of equatorialareas. Also fungus grows very fast in anequatorial climate. This fungus even consumesthe minerals within the solar panels renderingthem opaque to the flow of sunlight to thephotovoltaic cells (Noack-Schönmann Steffi,2012).

The other option of wind will not work unlesswith proper calculation of the dimension of thewind turbine in accordance to the low windspeed value. There is a formula below shouldbe used which gives the full dimension of thewind turbine given a specific average windspeed. The energy extracted from a windturbine is given by:

Ek = ½ MV² where M = AV x eff...(1)

where M = mass, = density, A = area, V =wind speed and eff = efficiency of the windturbine. Assuming the wind is in a form of acylinder of air. The theoretical maximumefficiency of a wind turbine is 16/27 or 59%,

Ek max = (½ AV³)16/27 ...(2)

This is Betz’ law, however empirically theamount of energy extractable from a windturbine ranges from 40 to 47% (Betz Albert,

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1946). Notable from this equation is that thewind speed is the most important factorbecause it is cubed in the equation. But windspeed is very low in the equator whereSarawak is located. Sailors of old dreaded theequator because they could be stuck in theseregions for months due to the lack of wind.Wind energy in the equator is possible only ifspecially designed wind turbines are used tocater for the low wind speeds. One windturbine project in Sarawak where a windturbine from a temperate country was justimported and planted (not considering thelocal low wind conditions) was a dismal failure.

Basically solar will work optimally desertslike Saudi Arabia, wind is for the North Seacountries like Norway. In equatorial Sarawak,hydroelectric dams is the best choice. Eachcountry should find her advantage and fullyutilize it and for Sarawak it is hydroelectricity.Also no power generator works as efficientlyas a dam because it uses only one engine,the generator.

The one older dam in Sarawak, the BatangAi has a relatively very low record of trippingand maintenance cost. The simple logic is thatin a dam, the falling water replaces thecomplicated Gas Turbine (GT), the coal firedsteam engine or and Internal CombustionEngine (ICE). Upon receiving a phone call fromthe power control center in Kuching, 300 MWof electricity from the Bakun dam can beloaded on the Sarawak grid within 30 seconds.This is compared to 45 minutes for a GT, anhour plus for an ICE, and eight hours for a coalpower station.

Also the staff at the Batang Ai powerstations do not face hazards of up to 103 dB(A)of sound pollution as in some parts of the ICE

power stations. The Preventive Maintenance(PM) at the ICE stations are also hazardous.Huge pistons the size of a truck need to betaken out and placed in a container of keroseneto be scrubbed manually. The diesel andkerosene outgassing have a very negativeimpact on the staff. At the GT in Bintulu the highfrequency noise attracts a four inch long insectcalled Emperor Cicada. The whole floor of thepower station is littered with these deadinsects. If it is cleared, the next day it will be fullagain. Apparently the high frequency noise theGT produces attracts the insects but they dieonce they reach the GT. If the power stationnoise can kill this insect, there must be someharm to humans. Statistically GT power stationstaff of Sarawak Energy Berhad (SEB) healthis relatively bad. On the other hand, thehydroelectric power station staff has the besthealth statistics in SEB.

Another advantage of the Batang Ai dam isthat it is normally used to balance out theinductive load in the grid when it is run as asynchronous motor to produce capacitiveVArs. Note that it is very easy to disconnectthe prime mover in a dam by just shutting theinlet water flow. In a GT power station, the gasturbine has to be separated from thegenerator via the contactless clutch which ismuch more difficult and often not possible. Incontactless clutch there is engine oil betweenthe GT and the generator instead of two platesclamping as in a car’s clutch. The GT’s shaftturns, resulting in a spin of the engine oil andthis spinning oil turns the generator shaft. It alsotakes 45 minutes for the GT to startup orshutdown so it is not normally run as asynchronous motor to balance the inductiveload of the grid. The difficulty of disengaging a

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prime mover from a generator in an ICE, GTor steam engine is the same reason they arethe last choice to run as a synchronous motorto produce capacitive VArs to balance themostly inductive VArs of industries (mostlyinduction motors).

Thus the majority of Sarawak’s electricpower is from hydroelectric dams. The othermajor source of electricity is coal powerstations, GT and ICE. Table 1 depicts the power

generation in Sarawak. Table 2 shows theforecast indicating an expansion of non-organicpower demand specifically to supply the heavyindustries currently being built in the centralportion of Sarawak. Table 3 shows the currentand power carried by the main power lines.

In gas turbines the input temperature of theburning gas and compressed air is 900-1400°C and the output is 450-650 °C. This exhaustgas is hot enough to heat up water to produce

SEB power generation May 2013

Capacity Running96 0

Bintulu (gas turbine) Spinning 6 X 33MW GT, reserve 2X100MW GT 350MW

513 405

79 60Total gas = 592

210 200

270 230

Total coal = 480104 80

1800 720

Total coal = 1904Total hydro = 1904Grand Total = 3072 1695

Biawak (ICE, GT)

Miri (gas turbine)

Power generation in Sarawak

Bakun (unit 3,4,5,6,7,8 atrunning=180MWcapacity=300MW)

Mukah (coal power)capacity 2 X 135 MW

1X115MW CombinedCycle

Batang Ai (hydro)

Sejingkat (coal power)Unit 1 & 2 = 50MW, 3 & 4=55MW

Table 1: Current Power Generation in Sarawak

Demand in MW 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020Organic load 991 1050 1113 1180 1251 1326 1406 1490 1580 1674 1775% Contribution 92% 77% 58% 42% 36% 32% 33% 30% 32% 33% 34%Energy intensive and export 90 307 807 1637 2217 2817 2817 3417 3417 3417 3417Total load demand 8 23 42 58 64 68 67 70 68 67 66Total Instaled capacity 1260 1850 3762 4570 4570 5170 5170 5720 6024 7024 7294Reserve margin (%) 14% 27% 49% 38% 24% 20% 18% 14% 17% 28% 29%

Table 2: Power Demand Forecast in Sarawak

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steam to run another generator. This is calleda combined cycle or Rankine cycle. Basicallya steam generator is a heat engine whichworks using the same logic as an airconditioner with four basic parts namely thecondenser, the evaporator, the compressorand the expansion valve. The combine cycle(gas turbine and steam engine) generator inBintulu produces 115 MW of electricity. Thecooling of the condenser in the combined cycleis done with sea water.

A good example of grid improvement forliterature review is the EriGrid Company onIreland to link up Leinster and Munster. Thisproject links to the line between Knockraha inCo. Cork to Great Island in Co. Wexford toDunstown, near Kilcullen, in Co. Kildare toensure high quality and reliable electricitysupply for homes, farms and businesses in thesouthern and eastern regions. It brings aboutbenefits such as:

• The grid line will helpto secure a futureelectricity supply for Leinster and Munster.

• Help to enable Ireland meets her 40%renewable electricity target as renewableenergy is integrated into the grid, therebyreducing reliance on imported fossilfuels.

• Improving the current grid in the south andeast of Ireland where the current supply isnot sufficient.

• Providing a platform for job creation in thesouth and east of Ireland.

• The project will facilitate further electricityinterconnection with the European grid(either Britain or France), providing a moresecure and reliable electricity system.

The current Ireland national power systemis an interconnected network of 400 kVtransmission lines which connects Moneypointpower station in Co. Clare to Woodlandsubstation in Co. Meath and Dunstownsubstation in Co. 220 kV and 110 kV lines arealso used in the grid. The overall transmissionline length is 6400 km.

Based on assessments report, it wasdetermined that the optimum solution was toconstruct a 400 kV AC overhead line linkingCork and Kildare via Wexford to meet theneeds for south and east.

These three connection point of DustwonSub, Knockraha Sub, and Great Island Subwere identify for this connection to enhancethe 400 kV grid because they aregeographically well-positioned to meet the

Table 3: 275 kV Existing Power and Current Carrying Capacity

275 kV Transmissionlines

MVA per circuit Total MVA withtwo circuits

Total current carriedby two circuits

Engkilili-Mambong 587 980 190Mambong-Matang 587 980 110Batang Ai-Engkilili 294 500 88Engkilili-Kemantan 600 1020 113Kemantan-Oya 600 1020 150Oya-Selangau 587 998 480Selangau-Kemenan 587 998 475Kemenan-Bintulu 587 998 535Bintulu-Similajau 587 998 210Similajau-Miri 587 998 90

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condition of the network development. TheIreland Grid link project estimated to cost $836million (EirGrid Plc, 2014).

Also in Europe, the InternationalElectrotechnical Commission (IEC) did aresearch to determine how extensive usageof renewal energy can be done to preventglobal warming and reduce dependence onimported fossil fuels. Their design envisagesa connection of grid to as large as possible tocater to the unavailability of solar energy duringa sudden cloud cover or unavailability of windpower during a sudden low wind situation.Large energy storage was also determined tobe one of the solutions. Batteries with liquidelectrodes have been suggested as a form ofgrid energy storage. Already the SynchronousGrid of Continental Europe which is alsoknown as the Continental Synchronous grid isthe largest electrical grid in the world. Thewhole grid is locked on a 50 Hz frequencyserving over 400 million customers in 24countries (International ElectrotechnicalCommission, 2012).

In the USA a large substation called the TresAmigas is being built to interconnect the threelarge grids of the USA, the WesternInterconnection, the Eastern Interconnectionand the Electric Reliability Council of Texas(ERCOT) grid. Electricity from each grid isconverted to DC and flows in a smaller DCHigh-Temperature Superconductor (HTS)wires in a 58 km2 area where any of the threegrids can pull out power or supply intermittentrenewal energy from wind or solar farms.Superconductors have the ability to keepelectrons flowing within it for long periods oftime making them energy storage devices. TheTresAmigas substation can initially handle 5

GW, expandable to 30 GW. HTS wires conductelectricity about 200 times better than copperwires of the same dimensions (Melhem,2012).

Salim, Prashobh et al. researched thepossibility of a solar and wind power forBorneo-wide power grid. This paperresearched on possible of incorporation ofsolar and wind power farm for Sarawak powergrid. With included potential location for solarand wind power generation in Sarawak.Simulations were made for the renewableenergy integration into the existing power grid.It takes into account the problems encounteredlike synchronization and when faults occur.Research was also conducted on the currentgrid control system, Supervisory and DataAcquisition System (SCADA) to study if it ispossible to replace it with a distributed internetbased network. This network runs on MultiProtocol Label Switching (MPLS) topology andcore and edge routers are connected withLocal Area Networks (LAN) at points ofgeneration and distribution connected by fiberoptics cables to form a wide areacommunication network (Salim Maaji et al.,2013).

The exploitable potential of hydroelectricityin Malaysia is 123 TWh per year. 70% of thislies in Sarawak, because of its abundantrainfall and topography. Sarawak hasnumerous rivers flowing down from steepmountain ranges at the border with Indonesia.Some of these ridges are of up to 1,200meters high.

The first dam built in Sarawak was theBatang Ai dam. This is a relatively small damcompleted in 1985 which produces 104 MW.The operation of the dam was so successful

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that the Sarawak government decided to buildother dams.

The Batang Ai Dam is a concrete-face rock-fill dam in Batang Ai National Park in Sarawak.The power station comprises four 26 MWturbines which totals to an installed capacityof 104 MW. Construction of the dam started in1982. The financing for the dam came fromthe Asian Development Bank. The constructioncaused a displacement of approximately 3,000people from 26 longhouses. These peoplewere moved into the Batang Ai ResettlementScheme where they were trained to cultivatecocoa and rubber but this program was notsuccessful. A mistake was made 1970s ofproviding each affected families quite a lumpsum of money. The villagers, who never sawsuch a great sum of money, lavishly spent it allin futile expenditures. Some even boughtMercedes cars for use in jungle roads, therebydestroying it in a short time. Most of thevillagers squandered all the money in a shorttime. Their minds were not ready or educatedto use this money. The best approach tohandle the villagers would have been to givethem a “salary” for the rest for their lives.

The next dam which is the Bakun dam wasbuilt at a cost of $2.4 billion. Construction ofthe 2400 MW dam began in 1993 initially as aprivate concern but later taken over by theMinistry of Finance of Malaysia. The BakunDam is located on the Balui River, a tributaryor source of the Rajang River. This dam is thesecond tallest concrete-faced rock filled damin the world.

The 205 m Bakun dam has a reservoir areawhich is 228 m above sea level with animpounded reservoir of 695 km². The

formation of the reservoir required resettling10,000 people.

There are eight penstocks of 8.5m indiameter each with lengths of 760 m. 16 rollergates control the water flow. The operatingwater level ranges from a maximum 228 m andminimum 195 m. The gated spillway withconcrete weir, chute and flip bucket has acapacity of 15,000 m3/s. The gross storagevolume is 43,800 million cubic meters. Thepowerhouse has a dimension of 250 m lengthx 48 m width × 48 m height. Each of the eightpenstocks supply water to the Francis turbinesof 300 MW which turns a 360 MVA air-cooledgenerator. This generator sends electricity toa 360 MVA transformer. Thus the total powersupply output is 300 X 8 = 2400 MVA. TheBakun dam came online on 6th August 2011.

Bakun was originally justified on the basisof supplying electricity to peninsula Malaysia.30% of the generated capacity was plannedto be consumed in East Malaysia and the restsent to Peninsular Malaysia. But this plan wasscrapped due to the high expense of theundersea cable between Sarawak andpeninsular Malaysia.

Currently the electric power from the damis supplied to the grid whose consumers areincreasingly the heavy industries located in theSamalaju Industrial Park. As of now there arefour large factories where 275 KV lines goesdirectly into the factory substations. Planningis also going on to enable the Sarawak grid tosupply the whole of Borneo island. This meanssupplying electricity to the other Malaysianstate of Sabah, the Indonesian territory ofKalimantan and the country of Brunei. Theoptimum way to do this is via DCinterconnections in-between grids. This way a

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of land. The displaced population has accessto a forest reserve of 19,500 hecters.

The Mukah power plant is an intermediarypower plant utilizing the low quality coal foundin Mukah. It cost $306 million to build which isa much cheaper initial cost than any of theplanned dams in Sarawak. To fire the two 135-megawatt (MW) steam turbines of the RM950-million Chinese-built Mukah plant, about 1.2million to 1.4 million tons of coal are requireda year generating 42,000 tons of ash a year.The coal reserves at the Mukah-Balingian Fieldcan last for 50 years if the Mukah coal powerplant is the only consumer. But another moreefficient coal plant is currently being designedto be built in Balingian.

The next dam in planning stage is the Baramdam. This planned dam will use four sets ofFrancis turbine to generate 1,200 MW. Thedam will be a roller compacted concrete typedam with a height of 185 m. Two saddle damswill be required to maintain full supply levelwithin the reservoir. This dam will impound areservoir of 388 km2. An estimated 6,000 to8,000 people from 32 longhouses will bedirectly affected by the Baram dam.

Sarawak needs the electricity that will besupplied by the Baram dam because demandfor energy from energy intensive large factorieslocated in Samalaju already exceeds currentsupply. The electricity from the Bakun andMurum (no output yet) dams has already beensold to energy intensive customers who haveinvested in Sarawak.

The development of the proposed Baramdam will also benefit the people of Baram asmajor roads are built to provide access to thedam sites. These roads will enable the

fault in say the Indonesian territory will not affectthe Sarawak grid (Maji et al., 2013).

The next dam is the Murum dam, built at acost of $1.25 billion. The dam is a RollerCompacted Concrete (RCC) dam of height of145 m with an impounded reservoir of 245km².The dam uses four penstocks to turn 236 MWFrancis turbine each, providing a total poweroutput of 944 MW of electricity. The spillway isnot gated. Sarawak Energy organized the damconstruction with the main contractor being theThree Gorges Dam Company which built thelargest dam in the world, the Three Gorgesdam in China. The Murum dam is scheduledto supply power to the grid on June 2014.

In the construction of the dam, ash fromburnt out coal from the Mukah coal powerstation was mixed with the concrete to makecement stronger. Actually this coal powerstation sold 42,000 tons of ash over the year2011. The ash from the Mukah power stationis stored in a silo to prevent dust pollution.From this silo, lorries carry it over a distanceof 400 km to the Murum dam.

In the construction of the Murum dam 1555people had to be resettled. The longhouse, thetraditional home of the resettled people wasconstructed for them in the resettlement area.This longhouse was constructed on as a twostory reinforced concrete frame sitting on stiltswith hard wood floor. In each home there is aliving room and three bedrooms. Eachhousehold within the longhouse is separatedfrom each other by a brick wall and every thirdhome is separated by a firewall. Otheraccessories provided are road, bridges,sanitation, drainage, water and power supply,community halls, chapels, kindergarten andgarden plots. Each family was given 14 hecters

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communities in Baram areas to be moreconnected to the towns and therefore marketsfor their farm or jungle produce. By reorganizingthese people in smaller resettlement areasthere will be more synergy as they worktogether to transport their produce to the towns.Also there will be better access to educationas schools are built for them. Access to townschool and tertiary education is also moreaccessible. The option of moving to town jobsand businesses will also be opened for them.When finally built, at least 20,000 people from25 longhouses will be displaced. The landcompensation will depend on the needs of thedirectly affected communities to support theirfamilies at the resettlement area. The peopleaffected by the dam will be compensated withhomes, including longhouse, land, cropsincluding fruit trees, graves, community hallsand Churches. The final decision on the exactresettlement site will be agreed on by the

directly affected communities themselves andthe Government.

Proposed Improvements to theSarawak GridThis work ventures into how the Sarawak gridsystem can be improved. The weakest pointin the Sarawak grid is the lack of lines carryingpower into the current load center of Kuchingcity. Something needs to be done about theKuching where most of Sarawak’s populationlives. Kuching does not have any significantpower generation at sufficiently low cost.Strategically the load center should not bedependent on a power source a few hundredkilometres away.

In the current setup, Kuching depends onjust two double circuits of 300 mm2 wiresbringing electricity into the city. These linescould be damaged by lightning strikes orsabotaged.

Figure 2: The Current Sarawak Grid

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The solution proposed in this paper isgeothermal energy. 37 km south of Kuching is

the Annah Rais Hot Spring where water surfacetemperature can reach up to 80 °C. This is

Figure 3: Single Line Diagram of Proposed Improvement to the Sarawak Grid

Figure 4: The Proposed Improved Sarawak Grid and New Power Source

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above the surface temperature of thesuccessful Salton Sea geothermal plantslocated near San Francisco whose surfacewater temperature ranges from 14-33 °C.Holes about two km are drilled below theSalton sea to access water at temperaturesof 260 °C which is sufficient for geothermalelectricity production. The existing coal powerplant in Kuching has an inlet steam of 533 °Cat a pressure of 7.62 Mpa to drive a 50 MWgenerator. The way to utilize a lower pressuresteam is to use many smaller generators. TheSalton Sea geothermal project uses 22generators to produce 800 MW of electricitywhich is be more than the demand of Kuchingcity. And all this is renewal. In fact geothermalenergy could potentially be a final solution tosolve all the world’s energy and global warmingproblem because no country that usesgeothermal energy need to import any fuel.Below the ground anywhere on earth there is

heat it is just a matter of how deep thegeothermal well need to be. In earthquakeregions where the larva is closer to the surface,the depth of the hole can be shallower (AdamsJeffrey, 2011; and Fridleifsson et al., 2013).

Kuching currently has an ICE that generates96 MW and a coal power station whichgenerates 200 MW. The coal power station isexpensive to run because the coal has to beferried in from 450 km away in Kapit,Sarawak. Sometimes the coal is importedfrom Indonesia. Overall it cost MYR0.11 perkWh to run. The ICE uses gasoline and costMYR0.22 per kWh to run. This is expensiveconsidering the average charge per kWh isaround MYR0.35. Currently the ICE is onstandby unless there is a power trip of thewhole grid. For ICE and coal power plants, sizeis important in the cost of the plant. The largerplant sizes benefit from economies of scaleand efficiency.

Figure 5: Current Sarawak Grid

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Other proposed improvement is theinstallation of solar farms in the existing ICEpower station named TAR, the existing Coalpower station named SEJ and in the hydropower station named BAI. This is nowpossible because solar panel manufacturingin China has driven down it’s cost world-widedrastically.

The second improvement is of courserunning more lines from the cheap powercenters to the load centers which are Kuching,Samalaju, Miri, Sibu and Bintulu. Figure 1shows the existing grid and Figure 2 is theimprovement proposed in this paper.

The Sarawak grid needs to be reinforcedby adding new transmission lines to create aring network around Sarawak. The current gridis not a ring and therefore any fault can bringthe whole grid down.

The improved designed optimum grid forSarawak is shown in Figure 3 single linediagram. The reinforcements that are neededare adding a 500 kV line starting at Bintulu tothe Similajau substation (sub) double circuitswhich is connected to Tada (Sibu) new sub andstop at Tondong (Kuching) new sub. From theTondong sub the 500 kV will be stepped downto 275 kV and link back to Mambong 275 kVsub and Matang 275 kV sub. At Tondong sub

Figure 6: Proposed Improved Grid Inclusive of New Power Stations

Table 4: Proposed New Transmission Lines

Transmission Lines Distance (Km)Tondong – SPC (132kV) 42Entingan-Mambong (275kV) 36Mambong-Tondong (275kV) 30Tondong-Matang (275kV) 29Tondong-Tada (500/275kV) 313Tada-Similajau (500/275kV) 192Tada-Oya (275kV) 30Tada-Selangau (275kV) 50Oya-Tanjung Manis (132kV) 40Bintulu-Samalaju (275kV) 18Tudan-Murum junction (275kV) 85

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a further step down from 275 kV to 132 kV willbe done and linked to SPC sub. At the Tadasub the 500 kV will be stepped down to 275kV and link back to Selangau 275 kV sub andOya 275 kV sub. The four subs that needreinforcement are Entingan 275 kV sub toMambong 275 kV sub. This will link up theMAM-ENT-ENG, Tudan 275 kV link to MurumJunction 275 kV sub to make up a ring circuitof TUD-MJU-SIM. At the Oya 275 kV sub astep down to 132 kV will be done beforeconnecting to Tanjung Manis 132 kV sub. Thiswill link up OYA-KEM-SAR-TGM. The Bintulu275 kV will be connected to Samalaju 275 kVto link up BIN-SIM-SJU.

The transmission lines that urgently need tobe reinforced are the OYA-SLG, SLG-KMNand KMN-BIN where the current loading is over50% of the line rating during normal operation.This is because there is a lack of powergeneration capacity in the southern portion ofSarawak and Sibu.

As Sarawak utilizes as much as possibleof her renewal hydroelectric potential she willattract heavy industries worldwide to site theirplants in this state. Big international companiesare increasingly being pressed to source theirpower away from coal. So it is a win-winsituation from all. Improving the grid to helpcarry all this power is critical in ensuringreliability of the whole system.

Another proposed improvement is to usenew technologies. One idea is to use LEAPengines. Basically the exhaust coming out ofa GT is hot enough to melt even the housingmaterial. So to solve this problem, highpressure air from the compressor is blown intoholes of the housing to cool it down. On theother hand in the LEAP engine the housing is

made of ceramic which can withstand the hightemperature of the exhaust. Thus thecompressed air need not be wasted to coolthe GT housing and can be utilized to producemore energy in the turbine. LEAP engines arecurrently being implemented in jet planes so aPurchase Requisition (PR) to General Electric(GE) is all it takes to build a LEAP engine GTfor power production (General Electric, 2014).

Another idea is the promotion of the use ofelectric cars. With everyone using Electric Cars(EV), these cars will be most of the time beplugged into the grid. Because peoplenormally drive to work for 20-60 minutes andpark the car for at least the next eight hours.They then take another drive home and plug itin for another eight to ten hours. For the fullutilization of EV there must be power socketsat all car parks such as is already done inScandinavian countries and in the USA statessuch as South Dakota, North Dakota andMinnesota. In these places the power at carparks is to heat up engines so that they canstart in the cold winters. With cars plugged intothe grid most of the day, they can be a backupstorage from which to pull electricity from. Thiswill be needed in case of a sudden cloud coverover solar panels, a sudden atmospheric windspeed reduction which impacts wind farms ora sudden mechanical problem which bringsdown an ICE, GT or hydroelectric generator.Of course an improvement which needs to bemade to the current Scandinavian car parkplug points is to install meters on them tomeasure electric flow to and from the EVs.

All these development will provide a lot ofpower supply to the state of Sarawak. TheSarawak government has two options to usethis power. One is to send it over the rest of

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Malaysia via a High Voltage Direct Current(HVDC) cable of 670 km to the nearest pointin the state of Johor, Malaysia. The secondoption is to attract huge heavy industries tocome over to Sarawak. The first option isbogged down by problems because 670 kmof undersea 300 mm2 HVDC will cost almostthat of a new Bakun Dam. Such a longundersea cable has also not been installedanywhere in the world. The energy loss in anundersea cable with it’s much highercapacitance could be too high to be viable.Power loss is increased dramatically withamount of XLPE (cross linked polyethylene)insulation used around the conductor. Thecapacitance in an underground cable isdepicted in Figure 3 and Equation (1) for singlephase and Figure 4 and Equation (2) for threephase (Eteruddin et al., 2012).

Farad

rrlC

c

i

ln

2

...(3)

Farad

rDlC

c

ln

2

...(4)

With the construction of the new 500 kVbackbone transmission line, there will be back-up to the current 275 kV grid. So if one failsthe other takes over. Also there is much greatercarrying capacity to move electricity all aroundSarawak. The latest protection systems shouldbe implemented in the substations. Previouslywith one 275 kV grid across Sarawak, therewas a great difficulty in implementing the latestsystems to help enhance power reliabilitybecause parts or the entire grid had to beshutdown to install the latest protection relays.With a 500 kV backup, upgrades can becontinuously be implemented as they aredeveloped by the big four in the power industrynamely GE, Siemens, ABB and Schneider.

There is also a need to more efficientlymanage the grid. The current SCADA Ethernetsystem from Harris Computers, USA is too

Conductor

Dielectric

rirc

Sheath

Figure 7: Cross Section of a Single PhaseCable Indicating Radius Used in

Capacitance Calculation

Figure 8: Cross Section of a Three PhaseCable Indicating Radius Used in

Capacitance Calculation

DD

r

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slow to respond to fault triggered, even thoughsignals are currently carried over fiber opticlines. An Internet Protocol suite (TCP/IP) basedsystem will enable much faster respond time.Currently many power corporations areconcerned about sending data over the internetbecause hackers may eventually control thegrid. But the current Ethernet can as easily behacked so that concerned is unjustified. Virusprotection from established anti viruscompanies like McAfee can be contracted tosecure the grid from hackers. The systemshould be automated as far as possible. Forexample if one generator in Bakun fails, takingoff 300 MW from the grid, a specified lowpriority load should be automatically sheddedimmediately to safeguard the rest of the grid.

CONCLUSIONWith all the improvement done on grid andpower source in Sarawak, it will boost updevelopments in Sarawak particularly themega power consumers in the Samalajuarea, thereby providing a solution to theextensive pollution in China caused by coalpower plants. The optimum grid and powersources will provide international investorshighly reliable, efficient, economical andsustainable electric supply. It should be notedthat Nikola Tesla who initiated the AC systemused worldwide, started his system withhydroelectric energy generated at the NiagaraFalls. This is what Sarawak is pursuing. Teslamade a statement that the world was notready for his inventions but one day it will beused. That prediction is proving correct asthe worldwide system is AC and his invention,the induction motor is driving the world’sindustry today.

A big political change has to happen toensure mankind move away from ICE vehiclesto electric vehicles which will be both a user ofelectric power as well as a perfect storage totake out power from, in case of an unplannedinterruption in power supply.

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Meeting on Renewable Energy Sources,November 3, pp. 59-80, Luebeck,Germany.

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