Optimization of electrical power production process for the Sibayak geothermal field, Indonesia

Abstract

Geothermal fluid in the Sibayak geothermal field is water-dominated. Seven production wells and 3 injection wells have been drilled. The old 2 MWe turbine has operated for 7 years. Plans to develop a new power plant by using the steam resources from the wells are underway. The main objectives of this paper are to design and to determine the optimum pressure for the technical operation of the system and optimize the electrical power production process. The most important result obtained shows that the optimum wellhead pressure of wells in Sibayak is in the range 9-13 bar-a. The EES program has proven very useful for calculations giving the turbine power output as 22 MWe and the power plant’s electrical power consumption as approximately 10% of the power from the turbine. The output from the turbine increases with lower condensing pressure as does the power consumption of the plant. Consequently, low condensing pressure will reduce the output from the power plant.