Energy Efficiency Comparison of Different Well Path Designs

Abstract Minimizing energy losses in production processes is necessary to enhance energy efficiency throughout a field's lifetime. The pressure drops occurring within production and injection wells to and from the production processing facility contributes to such losses. Well paths and completion configurations will impact the extent of pressure drop along the well paths. This study investigates the impact of various well path designs on energy efficiency and reservoir drainage strategies for a representative oil field and associated production system, including total energy consumption of the production processing plant and energy consumption per unit of hydrocarbon produced. This study uses the synthetic Egg reservoir model with a simple drainage strategy involving water and gas injection. Multiple well path designs, defined by their curvature, are used to construct pressure drop tables for production and injection wells. These inputs are integrated into the reservoir simulation and coupled with a simple optimization workflow for the production processing plant, with the processing plant being described by a mathematical model. The optimization controls the number of pump and compressor system stages and trains. Traditional reservoir simulation models provide field production and injection metrics, while the processing plant model employed in this project provides additional data on total energy consumption and CO₂ emissions. Seven well trajectories with varying lengths and curvatures are included in this study to assess the impact of well path design. To eliminate bias in the analysis, consistent drainage strategies, with constant liquid production and injection rates, and equal well completion configurations are applied across all cases, isolating the impact of well path design on energy losses over the field's lifetime. Simulation results reveal a relatively small impact from production well trajectories, with less than a 4% variation in hydrocarbon production and similar pressure drop profiles. Conversely, injection wells, particularly gas injectors, show significant sensitivity, with over 10% variation in pressure drop profiles. However, the results indicate little impact on total energy consumption for the tested cases. Since the volumes of hydrocarbons produced and injected are comparable, the primary distinction lies in the energy required to pressurize fluids to the discharge pressure of the production processing plant. The energy consumption differences for pressurizing fluids to the injectors are negligible. While the overall energy consumption of the processing plant remains largely unaffected for different well paths, the energy loss for different well-paths is significant when large holdup occurs in the well. By adding energy efficiency considerations on top of well productivity and economic performance, this study highlights that well path design has only a limited effect on energy efficiency. The small impact of well path on intra-well energy efficiency indicates that well paths are flexible to target field development goals without detrimental effects on intra-well efficiency. Well paths optimization can thus be conducted without including the efficiency of the wells in the objective function. Such a reduced objective function gives flexibility that can promote more sustainable well-path strategies.