Alternative of LNG cold exergy utilization for generating electrical energy at Gresik LNG receiving terminal

Gresik LNG receiving terminal will be built to meet the needs of combined-cycle power plant (PLTGU) with natural gas regasification rate of 60.95 MMSCFD. In conventional regasification process using open rack vaporizer (ORV), the potential of LNG cold exergy will be wasted to seawater which is used as a heat source from the environment. The commercially proven scheme of the regasification process with the utilization of LNG cold exergy to generate electrical energy such as Direct Expansion, Rankine Cycle and combined Direct Expansion+Rankine Cycle is simulated with Unisim computer software. The purpose of this study is to assess technically and economically three scheme mention above. The results show that the combined scheme has the ability to produce the largest electricity surplus of 39.80 kWh per ton LNG regasified with potential revenue from electrical energy sales of USD 1,140,935 per year. The energy and exergy analysis shows that this scheme also has highest thermal efficiency of 14.48% and highest exergy efficiency of 60.71%. However, based on the results of economic analysis found that Direct Expansion scheme has the highest NPV among the three schemes with a value of USD 695,032.