ENERGY AND EXERGY ANALYSIS OF DRY-STEAM GEOTHERMAL POWER PLANT IN KAMOJANG

摘要

The dry-steam geothermal in Kamojang is one of the biggest power plants in Indonesia with an installed capacity of 235 MW. This capacity was raised by five units of the power house, such as Unit 1 with a capacity of 30 MW, Units 2 and 3 each with 55 MW, 60 MW for Unit 4, and 35 MW for Unit 5. The Kamojang reservoir is considered as the best vapour-dominated reservoir in Indonesia with a temperature of 245°C. This research is aimed at calculating the rate of energy and exergy of Unit 3 using the engineering equation solver. The calculation requires the parameter, temperature, pressure, and mass flow rate which are obtained from daily plant data operation. Our observation showed that the first law of thermodynamic efficiency in Unit 3 of the Kamojang plant had reached 23.21%. The total exergy entering the system is at 295,789 kW. The exergy that can be converted into electrical energy is 100,863 kW with the second law of thermodynamic efficiency the plant had reached 34.10%. The biggest irreversibility occurs in the condenser reaching 178,190 kW or 60.24% of the total availability. Steam receiving header is the component with the smallest irreversibility with 264.2 kW or 0.09% of the total available exergy.