Engineering
Steam Power Plant (PLTU)
Steam Power Plant (PLTU) is a type of generator that uses "hot steam" to turn a turbine. The hot steam that is used can come from the process of evaporating water through a boiler, this plant uses coal fuel or fuel oil to heat water, as shown in Figure 1.
Gambar 1. Skema PLTU
The high volume of coal supplies both globally and in Indonesia and its low prices make coal-fired PLTU’s one of the highest production rates in electrical generation. At PLTU, coal is used as boiler fuel to produce heat energy which then functions to change the working fluid phase from liquid to steam. The kinetic energy contained in the steam is then used to turn a turbine connected to a generator. One of the main problems with the use of coal in electricity generation is the high emission of CO2 , which is a by-product of the coal burning process. The advantages and disadvantages of coal-fired power plants are summarized in Table 1.
Advantages
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Mature Technology
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Low fuel cos
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Longer lifetime usag
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Disadvantages
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High investment cost in the beginning
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High carbon emission
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Inflexible location,
Lokasi tidak fleksibel, wherever possible near ports or big water sources for cooling
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Table 1. Advantages and Disadvantages of PLTU
In its operation, the PLTU generally has components as shown below:
Gambar 2. Komponen pada PLTU
1) Boilers & auxiliaries
The boiler functions to convert water (feed water) into superheated steam which will be used to turn the turbine. Here the chemical energy of the fuel is converted into heat energy from steam.
2) Turbines & auxiliaries
Turbines function to convert heat energy contained by steam into rotational energy (mechanical energy). The turbine shaft is coupled with the generator shaft so that when the turbine rotates the generator also rotates.
3) Condensers & auxiliaries
The condenser serves to condense used steam from the turbine (steam that has been used to turn the turbine).
4) Generators & auxiliaries
The generator serves to convert the rotational energy from the turbine into electrical energy.