Intro to CO2 Pipelines: Vocabulary Guide

Carbon capture pipelines come with a whole dictionary of confusing terms that can leave your head spinning. You can bet that’s intentional – the industry doesn’t want us to understand what they’re doing. But, we aren’t going to be stopped by a bit of jargon, so we put together a vocabulary guide of commonly used terms to help break down the barrier. We based the definitions on how we hear them used within the carbon capture and storage space, but many of these terms are used similarly in other sectors. 

 

Abandonment: Permanently ending the operation of a pipeline or carbon storage site.

Anthropogenic CO2: Carbon dioxide generated by human activities.

Bioenergy with Carbon Capture and Storage (BECCS): A process that captures CO2 emissions from bioenergy production, such as ethanol plants, and attempts to store the CO2 underground.

Biogenic CO2: Naturally occurring carbon dioxide.

Caprock: A layer of rock that acts as a seal above an underground storage area that is intended to stop CO2 from escaping.

Capture plant: Equipment that captures, separates, and handles CO2 emissions from an industrial facility, such as an ethanol plant.

Carbon capture and storage (CCS): The process of capturing CO2 emissions from an industrial source like ethanol plants and injecting the CO2 underground to remove it from the atmosphere.

Carbon capture, utilization, and storage (CCUS): The process of capturing carbon dioxide and using it in industrial applications before or instead of underground storage.

Carbon intensity score (CI score): A measure of the greenhouse gas emissions created by an industry like ethanol. Loopholes like carbon capture allow a company to claim a lower CI score and appear environmentally friendly without reducing CO2 emissions.

CO2-enhanced oil recovery (CO2-EOR): Injecting CO2 into a nearly depleted oil field. The CO2 changes the viscosity of oil, allowing more oil to be extracted.

Common carrier: An entity that provides transportation services to the public under legal obligation to serve all customers without discrimination.

Compression station: A facility along a pipeline that maintains or increases pressure to ensure the CO2 continues flowing.

Computational fluid dynamics modeling (CFD modeling): A simulation tool used to show the potential impact area of a mass CO2 release.

Condemnation: The legal process by which private property is taken by eminent domain.

Decommission: Process of taking a pipeline out of service and returning the area to its previous state.

Dense phase CO2: CO2 in its liquid or supercritical phases.

Ductile fracture: A catastrophic pipeline failure where the pipeline can split, or “unzip,” for hundreds of meters. CO2 pipelines are particularly vulnerable to this type of failure.

Easement: A legal agreement allowing a company to use a landowner’s property.

Eminent domain: The government’s power to take private land for public use so long as just compensation is provided to the owner.

Flue gas: A mixture of gases released at the smokestack of an industrial facility.

Geological storage: Injection of CO2 underground.

Hazardous liquid: Used in regulatory contexts to describe substances, like CO2 transported by pipeline, that pose risks to safety or the environment if released.

High consequence area (HCA): Places where pipeline failures could have significant impacts due to population density, critical infrastructure, or environmental sensitivity.

Injection well: A well used to inject CO2 underground.

Intervenor: A stakeholder, such as a landowner or advocacy group, that participates in regulatory proceedings as an interested party to the case.

Inverse condemnation: A legal action where a property owner seeks compensation after their property is damaged by a public use.

Leakage: Unintended release of CO2.

Low consequence area (LCA): Areas where pipeline failures are less likely to cause significant harm due to lower population density or fewer critical assets.

Operator: Company that is legally responsible for the operation of a project. Often times, a company will form multiple LLCs so each part of a project (capture, transport, storage) is run by a different company.

Petition: A formal, written document submitted to a regulating agency that requests the agency make a decision.

Pipeline corridor: A designated area where pipelines are co-located. May also refer to the area surrounding a proposed pipeline route.

Pipeline inspection gauge (PIG): A device that is placed into a pipeline to clean, inspect, or maintain it.

Plume: The cloud of CO2 that could spread from a pipeline rupture or underground storage site.

Point source: Source of CO2 emissions from industrial processes.

Pore space: The area underground where CO2 could be sequestered.

Post-closure period: The period that begins after a storage facility is closed and CO2 injection has stopped.

Public use: The justification for taking private property through eminent domain, requiring that the project benefits the public, such as infrastructure or utilities.

Regulator: Agency that has the authority to permit, approve, or authorize projects.

Right-of-way (ROW): Used interchangeably with easement, this is the area of private property a pipeline company wants to take for their pipeline.

Satartia: Town in Mississippi that experienced a CO2 pipeline rupture.

Sequestration: The process of storing carbon dioxide underground.

Storage site: A site that comprises the storage facility and storage project wells.

Supercritical CO2: CO2 at pressures and temperatures above 88° and 1,040 psi, which gives the CO2 characteristics of both a gas and a liquid.

Survey: The process of examining or disturbing the land to see if it is suitable for a pipeline or well.

Well or wellbore: Holes in which combinations of tubing, casing, and cement are placed to move CO2 into the ground.

45Q: A U.S. tax credit for carbon capture and storage projects based on the amount of CO2 captured and stored.

45V: A U.S. tax credit for the production of clean hydrogen, which often incorporates carbon capture and storage.

45Z: A U.S. tax credit for clean fuel production that can be claimed by ethanol plants utilizing carbon capture and storage.