A New Mechanism in Determining the Number of Geothermal Wells for Power Plant Development Using Stochastic Method

Abstract

Abstract The number of geothermal wells (production, injection, make-up) should be calculated carefully to get the optimum values for the technical aspect of power plant development. However, the method for calculating the number of wells has been used is a deterministic approach that involves only a single value for every parameter. Since the result of this method is a single value, it cannot capture the uncertainties of the field parameters. Therefore, this paper proposed the newest method that applied 2-level full factorial design of experiment approach with the help from Minitab software to cover the uncertainties of the field parameters and to produce the probabilistic number of wells in combination with Monte Carlo Simulation. The proposed method has been successfully used to calculate the number of wells in the case study of Karaha-Talaga Bodas field. Based on the study, the most significant factors for determining the number of production and injection wells are the fluid enthalpy and total mass flow rate, whereas for the make-up wells number are the decline rate and make-up well capacity. 5 production wells, 1 injection well, and 4 make-up wells are the minimum requirement number of wells that should be drilled for generating 30 MW power plant capacity in 30 years.