Optimizing Well Productivity: Impact of Turbine Inlet Pressure in Cluster 9 at PT. Pertamina Geothermal Energy, Lumut Balai Unit

Geothermal energy, extracted from high-temperature reservoirs via deep wells, provides a low-carbon, sustainable alternative to fossil fuels. To optimize geothermal power generation, the study investigates the impact of turbine inlet pressure on well productivity at PT. Pertamina Geothermal Energy’s Lumut Balai Unit 1. By increasing the turbine inlet pressure from 4.3 barg to 4.9 barg, net power output rose from 52 MW to 56 MW, while gross power increased from 55 MW to 58 MW. However, this pressure adjustment also led to variations in system parameters, including increased wellhead pressures (e.g., LMB9-1: 8.02 to 8.13 barg) and changes in fluid flow rates—steam flow decreased from 149.2 to 135.7 tons/hour, while brine flow rose from 744 to 1,027 tons/hour. Despite the power gains, turbine efficiency slightly declined from 89.10% to 87.83%, highlighting a trade-off between higher energy output and operational efficiency. These findings underscore the critical role of turbine inlet pressure optimization in geothermal power generation. A balance must be struck between maximizing electricity production and maintaining efficiency. Strategic advancements in turbine operation and pressure control could significantly enhance Indonesia’s geothermal utilization, contributing to a more sustainable and energy-secure future.