The existing numerical and analytical models for fluid circulation in wellbores provide the necessary foundation for exploring geothermal energy prospects for generating power or hot water for various industrial usage. A steady-state fluid circulation rate in a closed-loop system provided insights into power generation’s efficacy in previous studies. Lately, the introduction of analytical modeling paved the way for exploring realistic scenarios for the time-variant geothermal gradient at a well’s proximity.
This article attempts to provide a roadmap for geothermal energy extraction by invoking the cyclical fluid circulation strategy for ensuring a stable surface fluid temperature or power. Both increasing and decreasing stepwise rate sequence provides the desired outcome. This rate-sequencing approach leads to assessing the value proposition of proposed thermal-energy extraction strategy in various North American basins. For a given depth, the overall thermal prospect depends on a well’s geographic location. Given the abundance of abandoned wells in oil fields, this study explores retrofitting such wells and drilling designed wells in geothermal-friendly areas to compare their relative economic value propositions.
Keywords thermal-energy, fluid circulation, designed wells, repurposed wells, power generation