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CCP - Glossary

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A reduction in the amount, degree, or intensity of emissions like CO₂.


The taking up and holding of a liquid or gas by a substance (a solid or liquid) through pores or gaps between molecules.


Taking up and holding (a gas, liquid, or dissolved substance) in a thin layer of molecules on the surface of a solid substance.


Organic chemical compound containing one or more nitrogens in -NH2, -NH or -N groups. In CCS, the main post-combustion carbon capture technology for separating CO₂ from flue gases or other gas streams is scrubbing the gas stream using an amine. After leaving the scrubber, the amine is heated to release high purity CO₂ and the CO₂-free amine is then reused. This technique can also be applied to coal-fired power stations – resulting in what’s known as ‘clean coal' – but with some additional cleaning of the flue gases.


This term describes effects, processes, objects, or materials (such as climate change) derived from human activities, as opposed to those occurring naturally and without human influence.


The layer of gases surrounding the planet Earth that is retained by the Earth's gravity. It is where CO₂ and other greenhouse gases are released and currently contains roughly (by molar content/volume) 78.08% nitrogen, 20.95% oxygen, 0.93% argon, 0.038% carbon dioxide, trace amounts of other gases, and a variable amount of water vapor.


The technical term for a geological structure whose rock is permeable enough to allow significant flow. These aquifers are bound by natural seals like cap-rock.

Basel Convention

UN Convention on the Control of Transboundary Movements of Hazardous Wastes and their Disposal, which was adopted at Basel in 1989.


The part of the Earth and its atmosphere in which living organisms exist or that is capable of supporting life.

Bituminous coal

A type of coal falling between the extremes of peat and anthracite, and closer to anthracite.


The tendency of a fluid or solid to rise through a fluid of higher density, including supercritical CO₂ through porous rock.


Layers of rock that are very difficult to permeate, allowing it to act as an upper seal to prevent a fluid from flowing out of a formation.


The removal of CO₂ from fossil fuels either before or after combustion. Estimates suggest that carbon capture and storage could reduce carbon emissions by 80–90% from a power station. Carbon capture and storage can be referred to as CCS.

Capture efficiency

The amount (as a fraction) of CO₂ that is removed or separated from the gas stream of a production source.

Carbon credit

A financial instrument that is transferable and saleable that provides an organization with a financial benefit from CO₂ emission reductions.

Carbon Trading

An approach that relies on public markets to allow producers with excess emissions to trade with those with reduced emissions. This ensures, with proper monitoring, that emissions levels stay within a regulated amount.

Carbon Dioxide (CO₂)

A colorless, odorless gas that is produced when animals (including humans) breathe or when carbon-containing materials (including fossil fuels) are burned. Carbon dioxide is essential to the photosynthesis process that sustains plant and animal life, however, it can accummulate in the air and trap heat near the Earth's surface (the 'greenhouse effect').

CO₂ avoided

The discrepant amount between CO₂ captured and stored and the amount of CO₂ which would have been produced by a system without capture.

Clean Development Mechanism (CDM)

A CDM allows a country with an emission-reduction or emission-limitation commitment under the Kyoto Protocol to implement an emission-reduction project in developing countries. Such projects can earn saleable certified emission reduction (CER) credits, each equivalent to one tonne of CO₂, which can be counted towards meeting Kyoto targets.

Climate change

Climate change is the variation in the average global or regional climate as measured by comparators such as average temperature and rainfall. The term has more recently been used commonly to describe arising from anthropogenic climate change.


Restriction of movement of a fluid (such as supercritical CO₂) to a specific place or space (like a storage aquifer or an oil or gas field in disuse).

Deep saline formation

An underground rock formation deep beneath the surface of the earth that is made up of permeable materials and containing highly saline fluids.

Demonstration phase

The demonstration phase is the phase when a technology is successfully deployed in a pilot project but is not yet proven to be economically feasible at full scale.

Depleted reservoir

A structure like an oil or gas reservoir where production is significantly reduced from past exploration.


Enhanced coal bed methane recovery; the use of CO₂ to enhance the recovery of the methane in unminable coal beds through absorbing the CO₂ on coal.


Enhanced gas recovery. EGR is the recovery of gas beyond the normal recovery produced by conventional extraction methods like fluid injection.

Emissions credit

A tradable financial commodity that gives its holder the right to emit a certain quantity of GHGs (q.v.).

Emissions trading

A trading mechanism that provides permits for the release of a predetermined number of tons of a pollutant which can later be bought, sold or traded.

Energy penalty

The loss of electricity generating capacity incurred when a cooling system is unable to perform at design efficiency. The energy penalty is associated with insufficient cooling of the turbine exhaust steam and usually is manifested by an increase in steam turbine back pressure. This study expresses the penalty as 'the percentage of plant output,' or phrased differently, 'the percentage of additional energy that would have to be used to generate the same amount of electricity.' In this study, the energy penalty also includes additional power needed for pumps and fans in cooling tower systems.


Enhanced oil recovery; the recovery of oil from a reservoir using means other than using natural reservoir pressure. Enhanced Oil Recovery generally results in the removal of increased amounts of oil from a reservoir when compared to employing methods using natural pressure or pumping alone.


Any material that is fed into a process (i.e. Coal, LNG) – particularly a raw material that constitutes the principal input for an industrial process like power generation.

Flue gas

Gases that are produced through the combustion of a fuel. These are gases normally emitted into the atmosphere.

Gas turbine

A machine in which a feedstock fuel is burned along with compressed air or oxygen which produces energy by the expansion of the hot products.


Process by which a solid fuel (generally containing carbon) is transformed into a fuel with carbon- and hydrogen-containing gases after reacting with air or oxygen and steam.


Greenhouse gases: carbon dioxide (CO₂), methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulphur hexafluoride (SF6).


Water beneath the earth's surface, often between saturated soil and rock, that supplies wells and springs.

Hazardous and non-hazardous waste

Hazardous and non-hazardous waste are types of waste which feature, or are excluded from, on the list of hazardous waste in the European Waste Catalogue (EWC) 2002.

Hazardous waste directive

A European directive that regulates the definitions of waste classes and the handling of these waste classes.


Integrated gasification combined cycle: generation method in which hydrocarbons or coal are gasified to be used as a fuel to drive gas and steam turbines.


A substance that cannot be penetrated. A rock or material that stops the movement of water or other liquids through it.


Substances inside a confined amount of liquid, gas, or solid, which differ from the chemical composition of the material or compound.


Using significant pressure to force gases or liquids into wells using pressure.


Intergovernmental Panel on Climate Change.

Kyoto Protocol

Protocol to the United Nations Framework Convention on Climate Change – adopted at Kyoto in 1997.


What happens when an injected fluid escapes from storage.

London Convention

On the Prevention of Marine Pollution by Dumping of Wastes and Other Matter – adopted at London, Mexico City, Moscow and Washington in 1972.


A sheet or block of material that separates selectively fluid mixture components.

Mineral trap

A geological formation that retains fluids through the reaction of the fluid – forming a stable mineral.


An anthropogenic intervention to reduce the anthropogenic forcing of the climate system; it includes strategies to reduce greenhouse gas sources and emissions and enhancing greenhouse gas sinks.

Natural underground trap

A geological structure which retains fluids by natural processes.

Observation well

A well specifically installed to permit the observation of subsurface conditions.


Organization for Economic Co-operation and Development.

Oxy-fuel combustion

This process involves burning fossil fuel in nearly pure oxygen rather than in air – producing a nitrogen free flue gas with water vapour and a high concentration of carbon dioxide as its main components. This also makes it easy to further concentrate the flue gas to an almost pure stream of CO₂.


Measure of rock composition that shows its ability to transmit or allow the flow fluids through its porous solid.


The production of more than one form of energy through a singular process.

Pore space

Space between rock or sediment grains that can contain fluids.


The ratio of void space to the bulk volume of rock containing that void space. Porosity can be expressed as a fraction or percentage of pore volume in a volume of rock.

Post-combustion capture

The capture of carbon dioxide after combustion.

Pre-combustion capture

The capture of carbon dioxide following the processing of the fuel before combustion.


A subsurface body of rock with the porosity and permeability to store and transmit fluids.

Saline formation

Sediment or rock body containing brackish water or brine.

Saline groundwater

Groundwater with dissolved salts.


A gas-liquid contacting device for the purification of gases or capture of a gaseous component.


To store something so that it is no longer available. Carbon sequestration involves the removal or storage of carbon dioxide so that it can’t be released into the atmosphere.

Solubility trapping

A process in which fluids are retained by dissolution in liquids naturally present.


A process for retaining captured CO₂ so that it does not reach the atmosphere.


Supercritical CO₂ means that the CO₂ is processed to have a temperature and pressure that is above its thermodynamic critical point. This state means that CO₂ can diffuse in solids like a gas and dissolve other materials like a liquid. This also means that density is compressed, thereby occupying a much smaller amount of space than it would in its natural state.

Synthesis (syn)-gas

A gas mixture containing a suitable proportion of CO and H2 for the synthesis of organic compounds or combustion.


Fuel, typically a liquid fuel, that is produced by processing fossil fuel.


CO₂ transport is the process of moving captured CO₂ through a pipeline or other vessel to a suitable storage site.


Man-made hole drilled into the earth to produce liquids or gases, or to allow the injection of fluids.

Well Integrity

The application of technical, operational and organizational solutions to reduce risk of uncontrolled release of fluids (like stored CO₂) throughout the life cycle of a well.


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Final results book available.


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