HEAT RATE GAP ANALYSIS BASED ON EPRI AND HEAT BALANCE METHOD (CASE STUDY in PLTU OMBILIN 2 X 100 MW)

• Main Author: Daniel Sihaloho, Ridho
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/43552
• Institution: Institut Teknologi Bandung

The performance of power plant will begin to decrease with increasing operating hours of power plant. PLTU Ombilin is one of the power plant that was established to strengthen the electricity system in the central part of sumatra and has been operating for more than 20 years so that the performance analysis is needed to identify that condition. In this study analyzed the performance of PLTU Ombilin Unit 1 based on the heat rate gap between commissioning and actual. Based on EPRI (Electric Power Research Institute), the analysis of the heat rate gap is done by mapping the dominant parameters causing heat rate losses. The amount of heat rate losses is determined by the gap factor which is the effect of changes in parameter values on the heat rate. The heat balance method is used to determine the gap factor values that are in accordance with power plant condition. However, the EPRI gap factor is obtained from the results of statistical calculations of several plants specified in the range value and average value. This study aims to determine the most suitable heat rate gap analysis by comparing the results of the heat rate gap analysis with the EPRI method and the heat balance method. Turbine heat rate calculation using cycle tempo software and boiler efficiency calculation using ASME PTC standard 4.1. The amount of deviation from the plant heat rate between commissioning and actual at 60 MW, 75 MW, and 90 MW in respectively is 234.98 kcal/kWh, 213.89 kcal/kWh, and 155.27 kcal/kWh. Comparison of the results of the heat rate gap analysis, the heat balance method is more accurate than the EPRI method because the total heat rate losses are the closest to the heat rate gap. The dominant parameters cause heat rate losses in the turbine cycle are main steam pressure, condenser backpressure, and makeup water with heat rate losses of 37.7 kcal/kWh or 62.7% of the overall heat rate losses in the turbine cycle while the dominant parameters cause the heat rate losses in the boiler are unburned carbon and excess oxygen with heat rate losses of 88.73 kcal/kWh or 91.68% of the total heat rate losses in the boiler.