Carbon dioxide capture, transportation and geological storage — Carbon dioxide storage using enhanced oil recovery (CO2-EOR)

1.1 Applicability

This document applies to carbon dioxide (CO₂) that is injected in enhanced recovery operations for oil and other hydrocarbons (CO₂-EOR) for which quantification of CO₂ that is safely stored long-term in association with the CO₂-EOR project is sought. Recognizing that some CO₂-EOR projects use nonanthropogenic CO₂ in combination with anthropogenic CO₂, the document also shows how allocation ratios could be utilized for optional calculations of the anthropogenic portion of the associated stored CO₂ (see Annex B).

1.2 Non-applicability

This document does not apply to quantification of CO₂ injected into reservoirs where no hydrocarbon production is anticipated or occurring. Storage of CO₂ in geologic formations that do not contain hydrocarbons is covered by ISO 27914 even if located above or below hydrocarbon producing reservoirs. If storage of CO₂ is conducted in a reservoir from which hydrocarbons were previously produced but will no longer be produced in paying or commercial quantities, or where the intent of CO₂ injection is not to enhance hydrocarbon recovery, such storage would also be subject to the requirements of ISO 27914.

1.3 Standard boundary

1.3.1 Inclusions

The conceptual boundary of this document for CO₂ stored in association with CO₂-EOR includes:

a) safe, long-term containment of CO₂ within the EOR complex;

b) CO₂ leakage from the EOR complex through leakage pathways; and

c) on-site CO₂-EOR project loss of CO₂ from wells, equipment or other facilities.

1.3.2 Exclusions

This document does not include the following:

a) lifecycle emissions, including but not limited to CO₂ emissions from capture or transportation of CO₂, on-site emissions from combustion or power generation, and CO₂ emissions resulting from the combustion of produced hydrocarbons;

b) storage of CO₂ above ground;

c) buffer and seasonal storage of CO₂ below ground (similar to natural gas storage);

d) any technique or product that does not involve injection of CO₂ into the subsurface; and

e) emissions of any GHGs other than CO₂.

NOTE Some authorities might require other GHG components of the CO₂ stream to be quantified.