Effect of Hydrogen Co-Firing with Natural Gas on Thermal Efficiency and CO₂ Emissions in Gas Turbine Power Plant

The Indonesian government has established an energy transition policy for decarbonization, including the target of utilizing hydrogen for power generation through a co-firing scheme. Several studies indicate that hydrogen co-firing in gas-fired power plants can reduce CO₂ emissions while improving efficiency. This study develops a simulation model for hydrogen co-firing in an M701F gas turbine at the Cilegon power plant using Aspen HYSYS. The impact of different hydrogen volume fractions (5–30%) on thermal efficiency and CO₂ emissions is analyzed under varying operational loads (100%, 75%, and 50%). The simulation results show an increase in thermal efficiency with each 5% increment in the hydrogen fraction, averaging 0.32% at 100% load, 0.34% at 75% load, and 0.37% at 50% load. The hourly CO₂ emission rate decreased by an average of 2.16% across all operational load variations for every 5% increase in the hydrogen fraction. Meanwhile, the average reduction in CO₂ emission intensity at the 100%, 75%, and 50% operational loads was 0.017, 0.019, and 0.023 kg CO₂/kWh, respectively.