Technology Overview

Gas turbine power generation is a technology that uses gaseous fuels (primarily natural gas) to drive turbines and generate electricity. This technology can operate in two main configurations: simple cycle gas turbine (SCGT) and combined cycle gas turbine (CCGT). In CCGT systems, waste heat from the gas turbine is used to generate steam for a steam turbine, thereby improving overall generation efficiency.

Technical Characteristics

The net electrical efficiency of CCGT is approximately 58%, while open cycle gas turbines (OCGT) achieve around 42%. OCGT offers advantages in fast start-up capability and operational flexibility, making it suitable for peak load applications. In contrast, CCGT is more suitable for baseload or mid-merit operation due to its higher efficiency. CO₂ emissions from gas-fired power are lower than those from coal-fired power.

Technology Comparison:

Technology	Investment Cost 2025	Configuration	Technical Characteristics
SCGT	~1.01 million USD/MW	Simple cycle gas turbine	– Simple configuration (single cycle)
CCGT	~1.14 million USD/MW	Combined gas and steam turbine	– Gas turbine reaches full load in <15 minutes – Steam turbine reaches full load in <1 hour
Hydrogen-ready CCGT (future option)	Not fixed	Can operate with a mixture of natural gas and hydrogen	– Capable of operating on natural gas–hydrogen blends – High flame speed and high combustion temperature – Potential for increased NOₓ emissions – Challenges in flame stability

 

Current investment costs are approximately 1.05–1.15 million USD/MW. Compared to coal-fired power, gas-fired power has lower capital costs and shorter construction time, while also supporting the integration of renewable energy due to its high operational flexibility.

Application in Vietnam

In Vietnam, gas-fired power is considered an important transitional technology in the energy transition process.