Analisis Reliability dan Improvement Program pada PLTP Kamojang Unit 1
Kamojang Geothermal Power Plant Unit 1 has installed capacity of 30 MW and has been operating as a base load system. It means that Kamojang Geothermal Power Plant must be able to supply electricity to the system for 24 hours continuously in a year exclude in the presence of repair or scheduled maintenance (periodic or corrective). Demand and market pressures encourage management to make further improvement of the reliability and availability to meet the needs in maintaining a stable supply of electricity to base load system.
Kamojang Geothermal Power Plant Unit 1 has been operating for 30 years. Thus far, there is no model of reliability and failure prediction applied. By knowing the pattern of reliability and failure prediction, the operation strategy can be specified. Reliability improvement programs are expected to maintain reliability and minimize the risk of force outage. To determine the reliability mode and failure prediction on turbines, generators and transformers, the modeling is proposed based on the Weibull Distribution - 2 Parameters Method. The data such as the number and time to failures in the equipment as well as the operation hours of equipment is required.
Reliability analysis shows the value of reliability prediction at the 245780 operation hours with 40% for turbine, 42% for generator and 31% for transformer. It will make the failure prediction value of turbine is 59 %, generator 58 %, and transformer 68% . Based on the reliability analysis and the actual condition of the equipment, improvement program is scheduled. Improvement programs for turbine are replacement of turbine gland packing material in 2014, providing rotors and diaphragm interchangeable in 2016, optimization and the effectiveness of turbine washing. The improvements for generator are rewinding of stator windings in 2015 and improvement of generator cooling performance in 2016. Some improvements for transformers are oil regeneration in 2014 and replacement of main transformer in 2015.
Financial analysis shows that IRR value for turbine is 28.87%, generator 51.81% and main transformer 69.57%. The payback period is 7 years for the turbine, 5 years for generator and 4 years for main transformer respectively.