**3. Malaysia hydropower information**

#### **3.1 Introduction to hydropower**

Hydropower is the conversion of Kinetic Energy (KE) of water into electricity and is considered a RES due to the water cycle being constantly renewed by the sun. According to an article on the US Geological Survey website, a hydropower dam works by having the water in the reservoir flow into a pathway called the penstock when the sluice gate is opened. This penstock is directly connected to the turbine, which is spun by the force of the water moving from a location of higher pressure to one of lower pressure. The water itself then flows out to a river below, whereas the turning of the turbine causes the conversion of KE from the water force into

*A Comprehensive Review on Available/Existing Renewable Energy Systems in Malaysia… DOI: http://dx.doi.org/10.5772/intechopen.96586*


#### **Table 2.**

*Net solar PV capacity and total addition by country from 2015 to 2018 [10,*

 *11].*

**Figure 2.** *Global PV cell production from 2015 to 2018 [12].*

mechanical energy for use by the generator, which is connected to it by way of shafts or gears. This turning of the turbine also causes the rotor within the generator to turn and consequently causes the electromagnets on its edge to move past the stators placed in a static position outside the rotor, allowing for the conversion of the mechanical energy from the turbine into Electrical Energy (EE). The electricity produced from this conversion process is then carried out to other locations and facilities by way of power to transmission lines connected directly to the generator.

#### **3.2 Hydropower in Malaysia**

International Hydropower Association states that the installed hydropower capacity is 6094 MW in 2016, with hydropower generating roughly 11% of the country's electricity and less than 20% of the technically feasible generation potential utilized to date in their article from May 2017 [14]. The following comparison has been done by choosing the most five powerful Hydropower plants in Malaysia.

#### *3.2.1 Bakun Hydroelectric Plant, Sarawak*

The Bakun Hydroelectric Plant is located on Batang Lui in the upper parts of the Rajang River, roughly 37 km upstream of the town of Belaga in Sarawak. The plant is powered by eight 300 MW turbines, allowing for an installed generation capacity of 2400 MW and has a power transmission system that directly connects to the existing power transmission network in Sarawak. The plant has been operational since 2011 and produces an average electricity generation of 1700 MW to 2110 MW depending on demands. The dam is considered to be the largest and tallest Concrete-Faced Rock-fill dam in South East Asia with a 205 m height and 750 m length, with the capability to contain 16.93 million m<sup>3</sup> of water, allowing the reservoir a surface area of around 695km2 with a catchment area of 14750 km<sup>2</sup> [13].

#### *3.2.2 Murum Hydroelectric Plant, Sarawak*

The Murum Hydroelectric Plant was completed back in 2016 and is located on the Murum River in the upper region of the Rajang River Basin, roughly 200 km

*A Comprehensive Review on Available/Existing Renewable Energy Systems in Malaysia… DOI: http://dx.doi.org/10.5772/intechopen.96586*

from Bintulu. The plant is powered by four 236 MW turbines, which totals to an installed generation capacity of 944 MW [13, 14], with its average production being around 635 MW and would be delivered through the state power grid. The dam is 141 m high and 473 m long, with a reservoir area of 270km<sup>2</sup> and a catchment area of 2750km<sup>2</sup> . The cost of the project totaled about RM 4.8 billion [15]. Besides that, Murum also has the world's tallest stepped chute spillway that helps to reduce KE by aerating the water overflow, which also helps to preserve the riverine ecosystem and the Batu Tungun rock formation, which is considered sacred to the local Penan community [14].

#### *3.2.3 Pergau Hydroelectric Station, Kelantan*

The Pergau Hydroelectric Station is located on the Pergau Lake, around 100 km away from Kota Bharu, Kelantan. The plant is powered by four 150 MW turbines totaling 600 MW of installed generation capacity and was designed to operate at a daily load factor of 25%. The Kuala Yong dam, which the power station receives its water from, is 75 m high [15, 16], with a 54km2 upper catchment and lower plain area. Besides that, the station also has a 1*:*<sup>5</sup> <sup>10</sup><sup>6</sup>*m*<sup>3</sup> reregulating pond designed to accept peak generation flows and to release them into the river in a controlled manner, which also had a generating cycle of 5.5 hours when at full station output. The cost of the project is totaling to RM 2.23 billion [17].

#### *3.2.4 Sultan Mahmud Power Station,Terengganu*

The Sultan Mahmud Power Station was completed in 1985 and located 55 km southwest of Kuala Terengganu on the Kenyir Lake. The plant is powered by four 100 MW turbines, totaling 400 MW of installed generation capacity, with continuous generation being 165 MW. The dam is 155 m high and 800 m long in crest, with a reservoir area of 369km<sup>2</sup> and a catchment area of 1260km<sup>2</sup> . The water height is around 120 m at minimum capacity and can go up to 153 m when it's at maximum, with a full supply level of 145 m [16, 17]. The lake itself can store 13.6 billion m<sup>2</sup> of water, with its deepest point being 145 m. Besides that, it can also release any excess water flow in the reservoir directly downstream into the Terengganu River.

### *3.2.5 Ulu Jelai Hydroelectric Power Plant, Pahang*

The Ulu Jelai Hydroelectric Power Plant was completed in 2016 and is located in the Cameron Highlands, Pahang on the Bertam River. The plant is powered by two 186 MW turbines which are placed in an underground plant [18], totaling to 372 MW of installed generation capacity for electricity. The Susu Dam, which is the dam that forms the Susu Reservoir of this hydropower plant, was built using almost 750,000m<sup>2</sup> of concrete through the Roller-Compacted Concrete (RCC) method, a very modern way to build such a dam. Said dam is measured to be 88 m high and 460 m long in the crest, with a 0.1km<sup>2</sup> catchment area. The total cost of the project was RM 4.2 billion and is expected to reduce 250,000 tons of carbon dioxide equivalent per year by substituting coal or fossil fuel-based generator stations during peak hours, according to a United Nations report [17, 18].

#### **3.3 Comparing the projects**

Based on the information gathered here, the five selected hydropower projects can be arranged and compared between each other within the categories of installed generation capacity, dam size, catchment area, reservoir area, and project cost (**Table 3**) [15, 18].

When it comes to total installed generation capacity, the Bakun has the highest of the five at 2400 MW, followed by Murum at 944 MW, Pergau/Sultan Ismail Petra at 600 MW, Sultan Mahmud at 400 MW and lastly Ulu Jelai at 372 MW. The reason behind the high output behind Bakun is not only it's high number of turbines, but the capacity of 300 MW that each turbine is capable of, which in and off itself is close to rivaling the entire output of the Ulu Jelai station at 372 MW. This makes it the most powerful hydroelectric power plant in Malaysia and the largest power generation facility in Sarawak, as it also supports the Sarawak Corridor of Renewable Energy (SCORE) initiative required for the energy-intensive heavy industries such as the Samajaya Industry Park. In terms of the dam sizes, Bakun has the largest at 205 m high and 800 m long, followed by Sultan Mahmud at 155 m high and 800 m long, Murum at 141 m high and 473 m long, and lastly Ulu Jerai at 88 m high and 460 m long. The length of the Pergau/Sultan Ismail Petra was not given but can be assumed to be the smallest of the five as the height is only 75 m. As for catchment area, which is a land area where water can flow into the plant reservoir [15, 18], the largest is Bakun at 14750km<sup>2</sup> , followed by Murum at 2750km2 , Sultan Mahmud at 1260km<sup>2</sup> , Pergau at 54km<sup>2</sup> and lastly Ulu Jerai at 0.1km<sup>2</sup> . Ulu Jerai is the smallest of the bunch as it uses the Bertam River, whereas the rest have a larger area to work with as they are built on lakes and other large bodies of water. Out of the five stations, only Bakun, Murum and Sultan Mahmud have a listed reservoir size at 695km<sup>2</sup> , 270km<sup>2</sup> and 369km<sup>2</sup> respectively. Having a reservoir allows for the storage of water as conversion fuel for a later date [17], meaning that Bakun has the largest water reserve of them all and thus can use more water to generate more electricity in comparison. When it comes to cost, the most expensive project was Bakun at RM 7.3 billion, Murum at RM 4.8 billion, Ulu Jelai at RM 4.2 billion, and lastly Pergau at RM 2.23 billion, whereas the cost for production of the Sultan Mahmud plant was nowhere to be found but could be assumed to be between Pergau and Murum due to the size being between those two and that it was completed in 1985. The cost of Bakun being the highest is because it uses more turbines that are very powerful in order to produce more power than the rest of the ones on the list combined at peak usage, not to mention the size of the construction project itself.

To wrap this part up, the Bakun Hydroelectric Plant is the best hydroelectric plant available in Malaysia due to the amount of installed generation capacity for electricity that it can provide due to the massive size of the project itself, but such power comes at a great price tag. In comparison, a project such as the Sultan Ismail Power Station or Pergau Hydroelectric Station would be a more feasible one to create in a higher quantity for a developing country such as this due to the lower


#### **Table 3.**

*The data for each of the five selected hydroelectric power plants.*

costs and less space requirement, while still capable of pumping out a respectable amount of electricity for the towns, villages and cities found in this country.
