David Hayes reports on the Malaysian Government's plans to increase hydroelectric power output in the country

GOVERNMENT plans to double hydroelectric power generation by the end of the decade are back on course again following the recent award of the civil works contract for Bakun dam in Sarawak, East Malaysia. Construction of Malaysia’s largest hydro power scheme is due to be completed in five years time and the first electricity supplied to customers by the end of 1997.

Several other hydroelectric schemes are also due for completion during the same period as Malaysia expands hydro power and coal-fired generation to reduce dependence on gas-fired generation. Plans include the development of pumped storage power in Peninsular Malaysia to make use of growing off-peak coal-fired power supplies.

Hydro power represents the largest indigenous renewable energy resource in Malaysia. The total amount of technically exploitable hydro potential countrywide is 123,000GWh per year. About 70% of this lies in the East Malaysian state of Sarawak due to regular tropical rainfall and the state’s topography which is characterised by numerous rivers flowing between steep, narrow, interconnected ridges rising up to 1200m high.

In a detailed survey on hydro potential carried out in 1980, a total of 51 hydro projects with an exploitable potential of 20,000MW and energy output of 87,000GWh per year were identified in Sarawak. The power from these projects constitutes the major portion of Malaysia’s unexploited hydro power resources.

Bakun dam

Among the various priority dam sites identified in Sarawak, the Murum and Bakun hydroelectric schemes are two of the largest schemes for which feasibility studies have been carried out, confirming their technical and economic viability. In 1994, the government decided to implement Bakun dam as an independent power producer (IPP) project targeted for commissioning in 2003. However, following the impact of the Asian financial crisis in 1997-98, the original government-appointed Bakun dam project developer, Sarawak tycoon Ting Pek Khing, was unable to proceed with the project and returned it to the government receiving US$110M compensation.

After deferring the project for three years the government has decided to revive Bakun, which will now be undertaken by Sarawak Hidro Sdn Bhd, a wholly-owned subsidiary of state-owned Minister of Finance Incorporated. Business analysts in Malaysia expect the government will try to privatise the Bakun project again with wealthy businessman Syed Mokhtar understood to be negotiating to buy a majority stake in Sarawak Hidro.

Engineering work began on 8 October 2002 on Bakun hydroelectric dam scheme and is being carried out by the seven-member Malaysia-China joint venture Berhad, while the main Chinese partner is China Water Resources and Hydro Power Engineering Corporation.

Construction work was completed early last year on the US$78.9M Bakun cofferdam and three river diversion tunnels, the first phase of the massive dam project. The US$2.4B hydroelectric dam project, which involves flooding an area the size of Singapore, will involve relocating about 10,000 local inhabitants away from areas that will eventually lie under water.

Bakun dam is scheduled to commence commercial operation by the fourth quarter of 2007. The project will have a total generating capacity of 2400MW, of which 1700MW is firm capacity.

Sarawak Hidro has tendered contracts for the dam’s electrical and mechanical works. Bids for the first set of four 300MW turbine generators have already been submitted and are being evaluated for the contract to be awarded.

Bakun dam power house will to be installed with eight 300MW turbines eventually. As Bakun will meet East Malaysia’s growing power needs for a number of years, no other major hydro power development schemes are likely to be needed for some time afterwards.

Aluminium smelter

Government support for Bakun dam is due to the prime pumping effect the massive project will have on the East Malaysian economy. Originally Bakun was planned to supply 1500MW of its power output to Peninsular Malaysia through a submarine transmission cable to help diversify the Peninsular’s growing power needs.

Constructing the submarine cable has now been abandoned as too costly. Instead, Bakun’s largest customer will be an aluminium smelting plant that will be built as part of Sarawak’s economic diversification programme.

At the end of March 2003, Sarawak Hidro and Smelter Asia Sdn Bhd announced they had reached agreement on the proposed bulk sale and purchase of electricity to be generated by Bakun dam, following the earlier signing of an MoU between the two parties.

Smelter Asia, a joint venture company between Gulf International Investment group and DUBAL, will develop an aluminium smelting plant on a 250ha site at Similajau near Bintulu on the coast of Sarawak. Construction of Smelter Asia’s aluminium smelting Phase 1 project for the production of 250,000 tonnes of aluminium ingots per annum is due to begin in 2005.

According to the recently signed power purchase agreement the amount of electricty to be purchased under the Phase 1 project is about 450MW.

However, the aluminium smelting production capacity is expected to double to 500,000 tonnes when Phase 2 is completed by 2012. As a result, the power purchase requirement will double to 900MW.

Electricity to be sold by Sarawak Hidro to Smelter Asia will be transmitted to the smelting plant by transmission lines to be constructed and owned by Sarawak Electricity Supply Corporation (SESCo), the state’s power generation, transmission and distribution utility. Smelter Asia will enter into a separate power transmission agreement with SESCo for this.

In addition, a three way agreement between Sarawak Hidro, SESCo and Smelter Asia will be necessary to ensure an unbreakable supply of electricity to the aluminium smelting plant.

SESCo will also supply electricity from Bakun dam to its existing customers. The utility plans to build a 700km double circuit HV transmission line from Bintulu to the state capital Kuching to reinforce the existing double circuit line and supply up to 1000MW of electricity from Bakun to customers along the transmission route.

Transmission schemes

Elsewhere in East Malaysia, Sabah Electricity Sdn Bhd (SESB), an 80% owned subsidiary of Tenaga Nasional Bhd (TNB), is constructing phase one of a US$254M East-West power transmission grid interconnection scheme to enable the utility to reduce its dependency on diesel and oil fuels by purchasing power from Bakun dam.

SESB supplies electricity in the state of Sabah. The first stage of the project connecting the areas of Sandakan, Lahad Datu, Tawau and Semporna was originally scheduled for completion by the end of 2001 but has been delayed to next year due to various factors including problems in obtaining way-leave permission.

Stage two of SESB’s grid interconnection is also due for completion by the end of 2004, while stage three of the power transmission line is due to be completed in 2005. Once the interconnection is completed and Bakun dam starts up, the power supply situation in Sabah will be greatly altered.

Sabah also has its own hydroelectric power potential that has been studied since 1994 and could be developed in the future. Several mini hydro schemes with capacities of 250kW to 1MW have been suggested to replace oil-based plants currently serving as isolated stations. Two larger hydro projects identified for implementation are the 165MW Liwagu hydro scheme in central Sabah and the 150MW Upper Padas hydro project in southern Sabah which would be able to generate a combined 1300GWh a year.

Peninsular Malaysia

Meanwhile, in Peninsular Malaysia where 18M of Malaysia’s total 23M population lives, government policy since the 1980s to utilise the country’s large natural gas reserves has led the Peninsular to become heavily reliant on gas-fired power generation.

While proven recoverable gas reserves lying offshore Peninsular Malaysia are sufficient to last another 20 to 30 years at the current rate of consumption, state-run Tenaga Nasional Bhd (TNB) plans to develop a more balanced power generation fuel mix programme by increasing the proportion of coal-fired and hydro power generation in future.

Currently about 80% of Peninsular Malaysia’s electricity output is generated by gas-fired stations while hydro schemes and coal-fired stations account for about 8.5% each of the Peninsular’s power production. In contrast, oil-fired units are used to generate just 2% of total power output.

TNB’s plans call for hydroelectric and coal-fired generation to increase to 20% each of Peninsular Malaysia’s total electricity output before 2010. TNB also plans to use coal-fired generation to increase hydro power output. TNB and Tokyo Electric Power Company of Japan have carried out a feasibility study on building a pumped storage scheme in Pahang State. TNB proposes to use off-peak power generated by the almost complete 2100MW Manjung coal-fired station to pump water into the upper reservoir at night for use generating peak load electricity the following day.

Development of hydro in Peninsular Malaysia dates back about 75 years to the pre-Second World War British colonial period. Malaysia’s oldest hydroelectric scheme is the Chenderoh scheme completed in 1927 in Perak State where the dam was built to supply electricity to tin mines. Rehabilitation work on the dam, which is part of the seven station Sungai Perak hydro power scheme, was completed in August 1999 when installation of three 10MW turbine generator sets was completed.

In November 1998, TNB formed a subsidiary, TNB Hidro Sdn Bhd, to manage, operate and maintain all TNB hydro power stations in Peninsular Malaysia including all generators, turbines, pumps, dams, spillways, gates, waterways and catchments.

Currently TNB Hidro operates 43 generating sets installed in 15 hydro power schemes. TNB’s largest dam is the 600MW Pergau scheme.

TNB’s plans to develop hydro power in Peninsular Malaysia include the construction of Kenyir II, the 300MW phase two scheme that will involve installing two 150MW turbine generating sets. The Japan Bank for International Cooperation has agreed to fund the project for which electrical equipment bids have been tendered and are now under evaluation.

Bidding opened in September 2002 and closed in December 2002. The project is an extension of Kenyir I.

Large hydro

Another area of interest to TNB is the rehabilitation and upgrading of various existing hydro power schemes. Contracts are due to be awarded in 2003 to rehabilitate the Cameron Highlands cascade scheme running over 50km in length through three states, Kelantan, Pahang and Perak, which consists of seven mini hydro and regular hydro power houses and includes three reservoirs.

The Cameron Highlands rehabilitation project is not being publicly tendered and is expected to be awarded on a negotiated basis. The smaller units range from 800kw to 2.5MW in installed capacity while larger units installed in the main stations include four 25MW and three 50MW turbine generating sets. The various turbines are understood to average about 40 years old.

Rehabilitation of each hydro station will be undertaken in two stages. Although the turbine generators can have an extended life, the auxiliary parts will need replacing. Also, TNB is asking for some automation to be installed to reduce manpower and help with operations and maintenance.