Grant: Alliance Grants

The Earth's subsurface will play a critical role in transforming the global energy system. Examples include geothermal energy (GE), hydrogen production and storage (HPS), geological CO2 storage (GCS), and critical element extraction (CEE). GCS, HPS, GE, and CEE are collectively referred to herein as "subsurface transitional energy pathways" ('STEPs'). Canada is committed to lowering its carbon footprint through reduction of greenhouse gas emissions and transitioning to alternative sources of energy; STEPs will be integral to this plan, leveraging the vast subsurface resources that Canada possesses. Technologies advanced and utilized in the commercial development of unconventional hydrocarbon reservoirs over the past 30 years will play a key role in the scale-up of STEPs to meet Canada's clean energy needs and emissions reduction targets. One such technology is multi-fractured horizontal wells (MFHWs), which are long horizontal wells hydraulically fractured in multiple stages along the well. Example applications of MFHWs to STEPs include enhanced geothermal systems (EGS), where water injection and producing well doublets are connected through a hydraulic fracture network to produce geothermal energy, and gas (CO2 or H2) injection for the purpose of permanent sequestration (CO2) or temporary energy storage (H2). The over-arching goal of this research program is to advance reservoir and hydraulic fracture characterization and evaluation methods, applied to MFHWs, to ensure the safe, efficient, and sustainable development of STEPs in Canada. New, low cost and time-efficient field testing methods, such as the diagnostic fracture injection test - flowback analysis technique, and the post-fracture pressure-decay analysis method, will be advanced for improved STEP system characterization, and to lower the risk of hazards such as induced seismicity. New laboratory methods will be advanced to obtain faster and more reliable estimates of STEP rock properties, and to evaluate the potential of organic-rich rocks (coal and shale) for purifying hydrogen-containing gas streams (e.g., effluent gases from the steam-methane reforming process).