3.2.3. Storage Project Phasing

Storage development is an iterative process that can be symbolized by a logical workflow in which one step can be achieved when the previous ones have been successful. Such workflows have been split into specific sub-tasks depending on the type of project (DSF, DOGF), the suitability of a given area, and its location (onshore shallow water, deep sea). Each sub-task is qualified with:

  1. A probability of success, which depends on suitability of the area where the project lies,
  2. A probabilistic distribution of cost, including regional cost factors, which depends on the type (DSF, DOGF) and on the environment (onshore, shallow water, deep sea), and
  3. A probabilistic distribution of completion time, which depends depend on the type (DSF, DOGF) and on the environment (onshore, shallow water, deep sea).

Taking into account these 3 characteristics lead to a key result of the present study: probabilistic distributions of success costs and development time are associated to each project. The above mentioned CO2 storage development workflows are described in Part 4.

Project development phasing for an onshore Deep Saline Formation (DSF) project up to bankability is shown in Table 1.

Table 1: Development phasing for a deep saline formation onshore storage project

Phase 0 corresponds to “state-led” initiatives to map global CO2 storage potential and capacity on a regional/national scale.

After this initial stage, exclusive surveys (Phase 1) led by industrial stakeholders (with state helps in the first storage development years), are performed.

Phase 1 corresponds to the feasibility study stage for a specific project and will be desk based assessment performed from Phase 0 results (when applicable) and other existing data. Some reprocessing of existing seismic and well data might be performed when available. The length and costs of this phase depends on the quantity and quality of the available data.

At the end of Phase 1, should its results be positive, an exploration license is supposed to be applied to relevant authorities for development of aquifer projects (site confirmation phase), while we suppose that solely an authorization for well drilling and/or workover for injection test would be applied to the same authorities for a project of CO2 storage in a depleted hydrocarbon field.

This site confirmation phase called Phase 2 is split in two parts:

  1. Exploration and site characterization
  2. Injection test

The first part of Phase 2 aims at acquiring local information to properly define the storage geological environment with additional seismic acquisitions and well drilling. The second part of Phase 2 is aimed at an injection test in order to finalize storage site characterization, injectivity assessment, containment mechanisms, and any elements making it possible to define the adequate industrial scale development.

At the end of this phase, the bankability of a storage project is then known.

As mentioned earlier we have developed iterative workflows to describe the process of characterization from Phase 0 up to end of Phase 2 (bankability). These workflows are described in next part (see Part 4).