WORKING PARAMETERS DESIGN OF ORGANIC RANKINE CYCLE AS A BOTTOMING CYCLE OF GEOTHERMAL POWER PLANTS IN WAYANG WINDU GEOTHERMAL POWER PLANT

• Main Author: Setia Febriatna, Triya
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/50124
• Institution: Institut Teknologi Bandung

Geothermal is one of the renewable energy sources with considerable potential in Indonesia, which is around 40% of the world’s potential. However, its utilization in Indonesia has only reached 1,948 MW. One way to optimize geothermal energy is to use brine that has high temperatures to become an ORC heat source as a bottoming cycle of geothermal power plants. Brine is a geothermal fluid that comes out from the separator with the liquid phase. The utilization of brine has a temperature limit to avoid scaling or silica deposition. With silica content of 723 mg/kg, the limit temperature is 132 ?C. The types of ORC used in the optimization process are simple ORC and ORC with recuperator using five types of working fluids, butane, isobutane, pentane, isopentane, and cis-butene. The optimization process is done by finding the turbine inlet pressure and working fluid mass flow rate which produces the optimum ORC electric power. Simple ORC produced optimum electric power when used cis-butene as working fluid and ORC with recuperator produced optimum electric power when used butane as working fluid. The optimum of simple ORC and ORC with recuperator then calculated the electric energy produced for one year by calculating the required power for the cooling system. The cooling systems used are water and air cooling system. From all the possible systems, a system that produces the largest of electricity for one year is chosen. The largest electricity generated for one year is 38,516,743 kWh, which is the ORC with a recuperator system that uses a water cooling system.