Abstract:
The increasing population and economic development impacted the rising global energy consumption. Whereby the gradual increase in energy consumption reflected the massive electricity demand. Currently, the trend to utilise solar panel renewable energy becomes an alternative to support the main power plant (PLN) to meet electricity demand. However, the uncontrollable weather condition caused the Rankine cycle to operate in partial-load condition. Unfortunately, the recent research has rarely discussed the efficiency of the Rankine cycle in partial load condition. Hence, the author focused on analysing the efficiency of Rankine cycle in partial load condition by using the combined cycle the subject of this research as the Rankine cycle in the combined cycle operate more often in partial load condition. In which, the author analysed the partial-load condition in the Rankine cycle by scrutinising thermal efficiency and steam turbine efficiency in the respective component of the Rankine cycle. To calculate Rankine cycle efficiency in partial load-condition, the author used the first law of Thermodynamics perspective and energy balance equations and used the actual operation data from Bekasi Power Combined Cycles. The relation between steam turbine output work and Rankine cycle thermal efficiency is obtained. The results showed, when the turbine efficiency reached and 78% and the power output in 46 MW, the thermal Rankine cycle efficiency reached 38%. Thus, it proofed that the Rankine cycle partial load condition in the combined cycle power plant can operate in a good partial-load condition.
