Apa Bedanya PLTG vs PLTGU ?

Summary

This video compares two types of power plants: PLTG (Gas Turbine Power Plant) and PLTU (Steam Power Plant). PLTG operates with just a gas turbine, offering lower efficiency, while PLTU uses both gas and steam turbines in a combined cycle, significantly increasing its efficiency. PLTG is less efficient with a 29% energy conversion rate, while PLTU can reach up to 43% efficiency by utilizing exhaust heat to produce steam. The video explains the mechanics, fuel usage, and efficiency differences between these two power plants, highlighting why PLTU is the more energy-efficient option for large-scale power generation.

Takeaways

• 😀 PLTG (Gas Turbine Power Plant) uses a single gas turbine to generate electricity, while PLTU (Steam Power Plant) uses both a gas turbine and a steam turbine in a combined cycle.
• 😀 PLTG operates on an open cycle, where exhaust gases from the gas turbine are released directly into the atmosphere, leading to lower efficiency.
• 😀 PLTU operates on a combined cycle, recovering exhaust gases from the gas turbine to produce steam, which powers the steam turbine, improving overall efficiency.
• 😀 The efficiency of PLTG is around 29%, as a significant amount of energy is lost through exhaust gases.
• 😀 PLTU's efficiency is around 43%, due to the utilization of both gas and steam turbines and the recovery of heat from exhaust gases.
• 😀 The key component differentiating PLTU from PLTG is the diverter damper, which controls whether exhaust gases are released or used for steam generation.
• 😀 Gas used in PLTG can be either diesel or LNG, and combustion requires compressed air to burn the fuel and generate power.
• 😀 PLTG systems typically use seawater for cooling purposes, especially when located near coastal areas, which is pumped through desalination plants to provide fresh water.
• 😀 The heat recovery steam generator (HRSG) in PLTU captures exhaust heat, using it to heat water and convert it into steam, which powers the steam turbine.
• 😀 The air used for cooling and as feedwater in PLTU is processed through various systems, including makeup water tanks and condensers, before being returned to the turbines.
• 😀 A higher number of heat exchanger fins in the HRSG improves heat absorption, leading to more efficient steam production and higher energy recovery from exhaust gases.

Q & A

What is the difference between PLTG and PLTU?

PLTG (Gas-Fired Power Plant) uses only a gas turbine to generate electricity, while PLTU (Steam-Fired Power Plant) uses both gas and steam turbines in a combined cycle to generate electricity, making PLTU more efficient.

How does PLTG (Pembangkit Listrik Tenaga Gas) work?

PLTG works by using a gas turbine powered by combustion of fuels like diesel or LNG. The exhaust gas from the turbine is released into the air in an open cycle, generating electricity with low efficiency.

What is the role of the Diverter Damper in PLTU?

The Diverter Damper in PLTU controls the exhaust gas flow from the gas turbine, deciding whether the gases will be expelled directly into the atmosphere or redirected to a heat recovery system (HRSG) to generate steam.

What is HRSG, and why is it important in PLTU?

HRSG (Heat Recovery Steam Generator) is a system that recycles waste heat from the gas turbine to produce steam. This steam is used to drive a steam turbine, significantly improving the efficiency of the power plant.

Why is seawater used in the cooling process of PLTG and PLTU?

Seawater is used for cooling in both PLTG and PLTU because it can absorb heat from the system efficiently. In PLTU, seawater helps in condensing the steam back into water in the condenser.

How does the process of water supply work in PLTU?

Water in PLTU is first drawn from a makeup water tank, then mixed with condensate water. It is pumped through multiple stages of heating to different pressures (high, intermediate, low) before being used to generate steam in the HRSG.

What is the purpose of the three pressure levels (HP, IP, LP) in PLTU?

The three pressure levels—High Pressure (HP), Intermediate Pressure (IP), and Low Pressure (LP)—are used to optimize the steam turbine’s efficiency. Each pressure level helps in driving the corresponding turbine stages and generating electricity.

How does PLTU improve the efficiency compared to PLTG?

PLTU improves efficiency by using waste heat from the gas turbine to generate steam, which drives an additional turbine. This combined cycle allows PLTU to utilize more energy, making it more efficient than PLTG, which only uses the gas turbine.

What happens to the exhaust gas in PLTG?

In PLTG, the exhaust gas, which can be as hot as 600-700°C, is typically released directly into the atmosphere. However, in combined cycle plants like PLTU, it is used to heat water to generate steam.

Why is the voltage of electricity increased in PLTU?

The voltage of electricity is increased in PLTU to reduce energy loss during transmission over long distances. Higher voltage reduces the current, minimizing the loss of energy in the form of heat.