Study of Increase Geothermal Well Production Rate by Downhole Pump Installation for Utilization in Power Plant

Abstract

Abstract A geothermal well is one of the main components in the geothermal field. The well is essential for geothermal utilization and connecting between reservoir and surface. Based on the condition to discharge fluid toward the surface, wells are categorized as self-discharge wells (able to discharge naturally to surface) and non-self-discharge wells (not able to discharge naturally to surface). For wells categorized as non-self-discharge with low pressure and low-medium temperature, an artificial method needs to be implemented, which is the use of downhole pump technology, namely electrical submersible pump (ESP) or line shaft pump (LSP). This condition occurs in well in Tulehu geothermal field (X-1). Downhole pump technology has been developed in several geothermal fields in other countries and has been proven to increase geothermal well production. The purpose of this research is to determine the appropriate engineering design for the implementation of a downhole pump in X-1 well and the net power output that can be produced. The research method was carried out analytically from evaluating and analyzing well-testing results, including completion test and production test to determine the condition and characteristics of the well, performing technical design calculation for downhole pump implementation, and calculating the binary cycle analysis of power plant obtain net power generated. Optimum pump setting depth in 600 meters depth that can produce mass flow rate 48.28 kg/s, and optimum model is ORC power plant with Butane working fluid that can produce Net Power Output 1.382 MW for ORC power plant model combined with ESP-2.