Proposed Guidelines for Carbon Capture & Storage (CCS) Completions Design in Highly Depleted Reservoir

TotalEnergies is committed to the goal of sustainability as it targets to achieve NetZero by 2050. One of the levers to carbon intensity reduction is to reduce direct emission from our portfolio and developing carbon sinks. Hence, the plan is to provide carbon storage services which would store equivalent of 50-100Mt/year of CO_{2 (TotalEnergies, 2023).} To realize this objective, the logical step is by building capacity, in terms of skills and projects, to adapt to the new requirements of CO₂ injection.

This ambition requires developing viable and sustainable surface and downhole equipment design which can meet the challenges of CO₂ injection. Our focus is the case of CO2 that is transported in dense phase to the well and then injected into a highly depleted reservoir. Among the challenges associated with the dense phase CO₂ injection into a depleted reservoir is the question of compatible completion strings, tubing connections and Downhole Safety Valve (DHSV); which form the primary well barrier, capable of handling potentially extreme low temperatures and rapid swings of temperatures associated with transient conditions of CO₂.

Thus far, we have proposed credible load cases for completions stress analysis and developed a methodology / guideline for completions design in highly depleted reservoir. Today, we routinely apply it to every project in focus; to incorporate CO₂ sequestration in the project development plans.

The results of this methodology clarify the specific need(s) for completions design and associated equipment qualifications for CCS applications in highly depleted reservoir environment.