Indonesia is country that owns large enough source of geothermal energy. One effort can be done by utilizing geothermal energy as source for electrical energy generation. To produce a source of electrical energy using ORC using water (H2O) as a working fluid. In this research ORC system uses Refrigerant R-141b as a work fluid for water experiment (H2O) used at Rankine cycle at general. There are 4 (four) main component ORC system namely Turbines, Condensers, Evaporators, and pumps. This experiment focused on Evaporator because it produces degrees superheating as energy source. Superheating steam is produced by Evaporator to turn Turbines and generators. Effect of degrees superheating phase change from liquid to vapor by analyzing Heat Transfer Coefficient. The filled evaporator is heated using a burner at temperature 105 °C,100 °C, 95 °C, and 90 °C. From result of experiments with increasing temperature, hot at same time temperature will increase Coefficient heat transfer and can produce higher heat. Changes in degrees heat from liquid to vapor phase become visible from simulation results. Refrigerant R-141b as a work fluid because of it volatile at low temperatures (T < 150 °C) and utilizes waste heat with low enthalpy.
- Immersed heat exchanger