The Effect of Inlet Water Intake Temperature on the Thermal Efficiency of Timor 1 Coal-Fired Power Plant (2x50 MW)

Abstract

In a thermal power plant, evaluating the performance of plant can be seen from the thermal efficiency value. Thermal efficiency is the percentage of heat energy entering the system that is actually converted into electrical energy. One way to increase the thermal efficiency of the plant is to reduce the temperature of the cooling water at the water intake inlet. From the research results, a graph shows the relationship between the increase in inlet water intake temperature from 30℃ - 33℃ to the condenser heat transfer rate, condenser pressure, and thermal efficiency of power plant. From the results of the calculations carried out, it was found that an increase in the inlet water intake temperature of PLTU Timor 1 (2x50 MW) from 30℃-33C, caused a decrease in the heat transfer rate in the condenser from 81,875 kJ/s – 81,873kJ/s, causing an increase in condenser pressure from 0, 0744 bar – 0.0872 bar and causes a decrease in thermal efficiency from 43.62% – 43.23%. So it can be said that the higher inlet water intake temperature, the lower the thermal efficiency of power plant. Lowering thermal efficiency from 43.62% – 43.23% will cause an increase in Levelized Generating Cost Value (LGCV) from IDR 1,284/kWh – 1,302/kWh. If LGCV multiplied by the annual kWh production, every 1℃  increase in water intake inlet temperature will increase production costs by 5 billion rupiah per year.