Application of Monte Carlo simulation for the estimation of production availability in geothermal well

Abstract

Abstract Wellbore simulation is one of the methods used in geothermal system performance analysis using a mathematical model of the geothermal system that considers parameters such as operating conditions, feed zone parameters, and well geometry. One of the methods used to perform wellbore simulation is the homogenous method. However, the results may still have a high level of uncertainty. To overcome this, probabilistic methods such as the Monte Carlo method can improve the accuracy of geothermal well production capacity modelling. The Monte Carlo method determines variability and uncertainty in the data being analysed. In determining geothermal well production capacity, the Monte Carlo method can take random samples of various influencing parameters, such as operating conditions, feed zone parameters, and well geometry. By conducting a Monte Carlo simulation, a more comprehensive probability distribution related to well production capacity will be obtained, considering the uncertainties associated with the available data. This research aims to determine the probability of production capacity of a candidate well in a geothermal field by considering uncertainty factors. In this research, a simulation is carried out until it converges using the Monte Carlo method so that the probability value will be obtained. Based on the analysis using the Montecarlo method, the probability of production capacity at the VY-1 Well of Vyatra Field is obtained, namely the P10 value with a large Mwe of 8.31 with an error of 0.102. Next, the P50 value obtained a Mwe value of 11.44 with an error of 0.001. Then P90 was obtained at 14.44 with an error of 0.012. Based on the analysis results, the most influential parameter in determining the production capacity of a Geothermal well is the productivity index value, followed by temperature and reservoir pressure.