Sustainable in-situ steam injection approach for shale oil extraction in Xinjiang, China: A technical and economic analysis

This work proposes a microgrid system for in-situ steam heating extraction of oil shale utilizing renewable energy sources. This system is designed for high efficiency and promises significant cost savings. This work couples the underground in-situ steam injection heating model and the microgrid system model to analyze the system's energy-saving and economics. Due to the technical and economic importance of Xinjiang oil shale in Northwest China, it is chosen as a case study to investigate the feasibility of the proposed method. The effect of steam temperature, pressure, and renewable resources at the oil shale extraction location on the economics of the system is examined. The results show that using renewable energy power is superior to hybrid and conventional power supply methods in terms of economy and energy efficiency. Moreover, renewable energy resulted in a 12.38 % reduction in the total net present cost (NPC) when the steam temperature increased by 40 °C. The total NPC of the project can be reduced by 28.61 % when the pressure of superheated steam is decreased by 4.0 MPa. The results indicate that the solar resource at the oil shale extraction location significantly impacts the system's economics. The study provides a theoretical basis for the economic analysis of oil shale steam injection extraction technology.