Glossary of terms

ABC

amine

A substance derived from ammonia by replacing one, two or three hydrogen atoms with hydrocarbon or other radicals.

anthropogenic

Resulting from or produced by human beings.

aquifer

An underground sheet of permeable rock through which groundwater runs.

carbon (C)

A chemical element found in all plants and animals on earth. All molecules that contain carbon are known as organic molecules. When fossil fuels are burned the carbon is released into the air and can join with oxygen to make carbon dioxide.

carbon capture

The removal of carbon dioxide from fossil fuels before or after combustion.

carbon capture and storage (CCS)

A process for reducing atmospheric emissions of carbon dioxide by separating it from industrial and energy-related sources, transporting it to a storage location, and safely isolating it from the atmosphere.

carbon cycle

The set of processes such as photosynthesis, respiration, decomposition, and air-sea exchange, by which carbon continuously cycles through various reservoirs, such as the atmosphere, living organisms, soils and oceans.

carbon dioxide (CO₂)

A naturally occurring, colourless, odourless, non-poisonous gas formed during respiration, combustion and organic decomposition.

carbon dioxide absorbent

A substance into which carbon dioxide is absorbed, such as an amine.

carbon monoxide (CO)

A colourless, odourless, very toxic gas made up of carbon and oxygen. It is the product of the partial combustion of carbon-containing compounds, notably in internal-combustion engines.

carbon sequestration

See carbon storage.

carbon storage

In the context of greenhouse gas mitigation initiatives, this phrase refers to the safe, long-term storage of carbon dioxide, usually deep underground. Sometimes called carbon sequestration, it is a component process of carbon capture and storage.

climate change

A change in the state of the climate that can be identified by changes in the mean and/or the variability of its properties, and that persists for an extended period, typically decades or longer.

coal gasification

The process of transforming coal into fuel through the reaction of coal, water and heat.

coal seam

An underground layer of coal.

coal seam gas

A natural gas formed as a by-product during the coalification process whereby organic matter is turned into coal. Also referred to as ‘coal seam methane’ or ‘coal bed methane’.

combined cycle

A process for power generation in which syngas or another fuel is used to drive a gas turbine that exhausts hot flue gases. Heat recovered from these gases, with additional firing, is the source for producing steam that drives a steam turbine. The turbines rotate separate alternators. See integrated gasification combined cycle (IGCC).

combustion

The process of creating light or heat by reacting certain chemicals with oxygen.

DEF

emissions trading

A market-based approach to reducing greenhouse gas that allows emitters (countries, companies or facilities) to buy or sell emissions permits from other emitters.

enhanced oil recovery (EOR)

A process for extracting otherwise inaccessible oil from underground deposits. It may involve flooding, carbon dioxide injection or other techniques.

flue

A duct where gases, fluids or air pass.

fossil fuels

Non-renewable energy sources including coal, oil and natural gas formed from the remains of living organisms. Fossil fuels are sometimes called non-renewable resources because they take millions of years to form, and reserves are being depleted much faster than new ones are being formed.

GHI

Garnaut Climate Change Review

Australia’s State and Territory Governments commissioned the Review in April 2007 to examine the impacts of climate change on the Australian economy and recommend medium to long-term policies. The findings of the Review will guide the Australian government in developing its policy responses to climate change.

geosequestration

Geosequestration is the process of storing CO₂ in underground geological formations for the primary purpose of mitigating greenhouse gas emissions.

geothermal power

Energy generated by heat stored in the earth, or the collection of absorbed heat derived from underground in the atmosphere and oceans.

gigatonne (Gt)

One thousand million tonnes.

global warming

Global warming refers to the gradual increase, observed or projected, in global surface temperatures.

greenhouse effect

greenhouse gases absorb infrared radiation, effectively trapping heat near the earth’s surface. Higher concentrations of greenhouse gases in the atmosphere caused by the activities of humans are believed to be causing a rise in average global temperatures.

greenhouse gases

Gases in the atmosphere, such as water vapour, carbon dioxide, methane and nitrous oxide that create a greenhouse effect, trapping heat near the earth’s surface.

hydrocarbon

An organic compound containing only hydrogen and carbon, including coal, peat, oil and natural gas.

hydrogen (H)

A colourless and odourless gaseous element, it is the lightest and apparently the most abundant chemical element in the universe.

integrated gasification combined cycle (IGCC)

A process for generating power that integrates coal gasification with combined cycle combined cycle turbines.

Intergovernmental Panel on Climate Change (IPCC)

IPCC is a scientific intergovernmental panel set up by the World Meteorological Organisation and by United Nations Environment Programme. It provides reports that assess the latest scientific, technical and socio-economic evidence on climate change. It is the world's pre-eminent scientific advisory body on climate change.

International Energy Agency (IEA)

Established in 1974, the agency is linked with the Organisation for Economic Cooperation and Development (OECD). It enables OECD member countries to take joint measures to meet oil supply emergencies, to share energy information, to coordinate their energy policies, and to cooperate in developing rational energy use programmes.

JKL

Kyoto Protocol

The Kyoto Protocol is an international agreement sponsored by the United Nations Framework Convention on Climate Change United Nations Framework Convention on Climate Change. Developed nations that sign the Kyoto Protocol, including Australia, agree to reduce their greenhouse gas emissions to 1990 levels by 2008-2012.

low-emissions coal technology

A technology associated with power generation, mining or other coal-related industrial processes that, over its life cycle, causes less greenhouse gas emissions than other technological options. Carbon capture and storage is one of a range of low-emissions coal technologies.

MNO

methane (CH4)

One of the six greenhouse gases to be mitigated under the Kyoto Protocol. It is the major component of natural gas and associated with all hydrocarbon fuels, animal husbandry and agriculture. It is also a by-product of the coal formation process and is released when coal is mined. See methane capture and use.

methane capture and use

In many underground mines, methane has to be drained from the coal seam prior to mining to ensure safe working conditions. In some cases, it is used to fuel gas turbines for mine site and for urban electricity generation.

oxyfiring

See oxyfuel combustion.

oxyfuel combustion

The process of burning fuel such as coal in pure oxygen instead of air.

PQR

permeability

The capability of a rock (or other material) to allow the passage of a fluid or gas. Permeability depends on the size of and the degree of connection among a substance's pores (see porosity).

petajoule (PJ)

A joule is a unit of energy. A petajoule is 10 to the 15th joules (10 followed by fifteen zeros).

photosynthesis

The process by which plants take carbon dioxide from the air (or bicarbonate in water) to build carbohydrates, releasing oxygen in the process.

porosity

The ratio of the volume of pore space in rock (or other material) to its total volume. Porosity determines a material’s ability to absorb a liquid or gas.

post-combustion

A system that captures CO₂ after combustion.

pre-combustion

A system that captures CO₂ before combustion.

renewable resources

A natural resource qualifies as a renewable resource if it is replenished by natural processes at a rate comparable to its rate of consumption. Wind, solar, oxygen, fresh water, timber, and biomass can all be considered renewable resources. However they can become non-renewable resources if used at a rate greater than the environment's capacity to replenish them.

royalties

In the mining industry, these are monies paid to parties involved in the mining process, especially landowners, including the government.

STU

saline aquifer

An aquifer that holds an abundance of salty water.

saline formation

A layer of porous rock that holds an abundance of salty water.

subsidence

The lowering of the earth’s surface, caused by such factors as compaction, a decrease in groundwater, and mining.

supercritical

Supercritical is a term used to describe a substance at a temperature and pressure above its thermodynamic critical point. It can diffuse through solids like a gas, and dissolve materials like a liquid.

syngas

A mixture of carbon monoxide (CO) and hydrogen (H2), which is the product of the gasification of organic material such as coal.

United Nations Framework Convention on Climate Change (UNFCCC)

UNFCCC was established in 1992 and currently has 189 signatory parties. An international framework was agreed that aimed at stabilising atmospheric concentrations of greenhouse gases. The UNFCCC agreed to the Kyoto Protocol in 1997 to implement emission reductions in industrialised countries.

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