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A reduction in greenhouse gas emissions as a result of actions taken by a company or individual.


The transfer of energy from one material to another, with a possible change in form. For example, the sun's energy can be absorbed by water, which is heated and becomes steam that can be used to generate electricity.

Alternating current

Electricity that changes direction periodically. The frequency of AC power is measured in cycles per second or hertz. The electricity used in a house is AC power.

Appraisal well

A well drilled for the purpose of determining the size of an oil or gas reserve.


Electricity generation that provides a steady supply of electricity day and night.


The variety of living organisms in the world or within a given habitat.


A fuel produced from biomass.


Biomass is the name given to all plants and animals (including humans) on Earth.

Black energy

Energy generated from burning coal and other fossil fuels.


Barrels of oil per day.


Something that is created during the manufacture of something else. For example, sawdust is a by-product of furniture making.

Capacity factor

The actual output of a generation plant compared to the expected maximum output from the plant in that period.


Carbon dioxide (CO2). 'Carbon' is now often used as a short-hand way of referring to greenhouse gas emissions, largely because it is one of the main gases causing climate change.

Carbon capture

A technological solution for capturing carbon dioxide as it is released into the atmosphere; for example, geosequestration.

Carbon dioxide (CO2)

A colourless, odourless gas that is present in the atmosphere. It can be produced naturally (through respiration) or as a by-product of oil and gas production or the burning of fossil fuels and biomass.

Carbon footprint

A measure of the amount of carbon dioxide equivalent emitted can be measured on various levels, such as personal, business or national.

Carbon intensity

Carbon dioxide equivalent emissions per unit of energy.

Carbon offset

A financial payment that is used to compensate for greenhouse gas emissions from one's own activities; for example, growing trees to sequester carbon. Offsets can be bought by a business or individual in the voluntary market or within a carbon trading scheme. A carbon offset usually represents one tonne of CO2e.

Carbon price

An Australian Government legislated scheme to address climate change under the Clean Energy Act 2011, officially known as the Carbon Pricing Mechanism. Under this scheme Australia's largest emitters of greenhouse gases must pay the Government for each tonne of carbon they emit to encourage a shift to a lower carbon economy.

Carbon storage

The long-term storage of carbon in forests, soil, oceans or underground in depleted oil and gas reservoirs, coal seams and saline aquifers; sometimes called 'carbon sequestration'. carbon capture and storage can be referred to as CCS.

Cased and suspended

A well that has had a steel casing installed to enable future production.

Charge point

A common term used to describe where an electric car can be re-charged; located at a home, work site or in a public place.

Chemical injection lines

Devices built in close proximity to gas pipelines and used to treat the raw gas so that it is suitable for processing.


A series of electrical conductors, wires and components that allow an electrical current to flow.

Circuit breaker

A device that protects a circuit from power surges by stopping the flow of electricity.

Climate change

Any change in climate over time, whether due to natural variability or as a result of human activities.


A combustible black or brown organic sedimentary rock, comprising mostly carbon and typically found as layers (coal beds) or veins (coal seams).


A process that allows energy to be efficiently produced on site, using natural gas-powered engines to produce two types of energy in the same process: electricity and heat.

Combined cycle power station

Power stations that have both gas and steam turbines and are usually used for baseload power. The gas turbine generates electricity using natural gas as a fuel, while the steam turbine generates electricity using waste heat from the gas turbine.


The transmission of electricity, sound or heat.


A material or object which allows an electrical current to flow freely in one or more directions.


The transfer of heat through a liquid or gas (such as water or air).

Conventional gas

A form of natural gas that is found in permeable sandstone reservoirs and is easy to get out of the ground through traditional well drilling techniques.

Crude oil

A naturally occurring substance found in underground rock that is formed from hydrocarbons, organic compounds and small amounts of metal. Crude oil can range in colour from clear to black and is a source of energy that, when burnt, is used to make petroleum and other products.

Decentralised electricity

The generation of electricity from small energy sources that are close to the point of use, such as solar photovoltaic (PV) panels and cogeneration plants.


The breaking down of certain organic matter (such as plants or animals).

Development well

A well drilled to enable production from a known oil or gas reservoir.

Direct current

An electrical current which flows only in one direction in a circuit. Batteries and fuel cells produce direct current.


Transportation of electricity to homes and businesses along power lines.


A machine that converts moving energy into electrical energy. For example, in a hydroelectric station, flowing water causes a turbine to spin. A dynamo turns the energy created by the spinning turbine into electricity.


The overhanging edges of a roof.

Electric cell

A device that produces or stores electricity, such as a battery.

Electric meter

A device that measures the amount of electricity used.

Electric vehicle

A vehicle whose motor is powered by electricity from a rechargeable battery as opposed to petrol or diesel as in a traditional vehicle.

Electrical current

The rate at which electricity flows through an electrical conductor, usually measured in amps.

Electrical resistance

The interruption to the flow of charged particles, such as electrons.

Electricity grid

An interconnected network that carries electricity from suppliers to consumers.


Substances released into the environment.


Environment Protection Authority or equivalent state authority.

Exploration well

A well drilled to identify a new reservoir of oil or gas.

Feed-in tariffs

A policy mechanism to encourage the development of specific electricity generation technologies. A per unit subsidy is paid to a particular technology, such as solar photovoltaic (PV) panels, in order to make that technology cost-competitive with other generation sources.

Flat rate

A pricing contract with a retailer in which the customer is charged the same per unit rate for electricity at all times of day and on all days of the week.

Fossil fuels

Fuels such as coal, oil and petroleum that are derived from fossilised organic matter.

Fugitive emissions

Commonly used term to refer to carbon emissions (usually methane) from some aspects of coal mining, oil and gas production, and natural gas pipelines.


A safety device that protects electrical appliances by preventing the flow of too much electricity into them. The fuse is a thin wire inside a protective case. If the flow of electricity becomes too powerful, the wire melts and stops the current flowing.


An air-like state of matter, sometimes used to describe hydrocarbons such as methane (CH4) and ethane (C2H6) that exist in a gaseous state at room temperature conditions.

Gas measures

joule: the primary measure of energy in the metric system.
gigajoule (GJ): equal to one billion joules.
terajoule (TJ): equal to one thousand gigajoules.
petajoule (PJ): equal to one thousand terajoules or one million gigajoules.

The factors used by Origin to convert to PJe are:
One million barrels crude oil = 5.83 PJe.
One million barrels condensate = 5.41 PJe.
One million tonnes LPG = 49.3 PJe.
One TWh of electricity = 3.6 PJe.


The process of transforming energy from coal, gas, falling water, sunlight, wind and geothermal heat to electrical energy.


Processes and technologies to capture and store carbon dioxide underground.

Geothermal energy

The energy contained in natural fluid reservoirs and rock formation in the earth's crust, which can be extracted usually in the form of high-pressure steam and used to power turbines to generate electricity. The fluids are returned underground.

Gigajoule (GJ)

One GJ = one billion (1,000,000,000) joules.

Global warming

A gradual increase in the average temperature of the Earth's climate, caused by the greenhouse effect.

Green energy

Energy generated from sources such as hydro power, solar, biomass or wind; also known as renewable energy.

Greenhouse effect

Heat from the sun passes through the Earth's atmosphere and heats the Earth's surface. Some of the heat that is reflected back becomes trapped by the atmosphere causing the Earth's temperature to rise.

This is a natural effect that allows the Earth to maintain a temperature that supports life. However, when excessive levels of greenhouse gases, such as carbon dioxide or methane are released into the atmosphere they cause more of the Sun's rays to become trapped, leading to a faster rate of warming.

Greenhouse gases

Gases that trap the heat of the sun in the Earth's atmosphere. They can be naturally occurring, or the result of human activities. The most common greenhouse gases are carbon dioxide and methane.


A voluntary government program that allows an energy retailer to buy green energy on a customer's behalf. This means that the proportion of renewable energy in the grid is increased by the equivalent amount of the GreenPower the customer purchases each year.


The transmission and distribution networks that deliver electricity from generators to consumers such as homes and businesses.


To direct the force (or energy) of something. For example, solar panels can be used to harness the energy of the sun.

Hybrid electric car

A vehicle that uses two systems: a rechargeable battery which can be plugged into an external power source, and another system which makes power from a fuel, such as petrol or diesel, to increase the range of the vehicle.


Using the power of water to generate electricity.


A particle or molecule made of hydrogen and carbon atoms, such as methane (CH4).


Using the energy from falling or flowing water to create electricity. Hydro-electric plants use the energy of water in dams and flowing rivers to turn turbine blades. The rotating blades spin a generator that turns the mechanical energy into electrical energy.

Hydrothermal energy

Power generated from heating fluids, such as water. Steam is produced from the heated fluids which acts to power a generator, producing electricity.

Incandescent light globes

The traditional pear-shaped light bulbs, which use five times more energy than compact fluorescent lamps (CFL).


Materials in your home (such as insulation foam or batts in the roof) which prevent heat transfer (i.e. the loss of generated warmth in winter and the entrance of the sun's heat in summer).


A material that reduces or stops the flow of electricity.

Interval meter

A meter that measures and stores electricity usage data over short periods of time (for example, every 30 minutes) as opposed to a traditional meter which needs to be read manually.


A joule is the primary measure of energy in the metric system.


Equal to one thousand barrels.

Kilowatt (kW)

Used to measure electricity. One kW = one thousand (1,000) watts.

Kilowatt hour (KWh)

The standard unit of electrical energy that represents the consumption of one kilowatt over the period of one hour.

Kinetic energy

The energy of objects that are moving.

Light oil

Lighter fuel oils distilled off during the refining process.

Mains electricity

Electricity supplied to homes from the national grid.

Marine energy

Uses the power of waves and tides to turn turbines and generate electricity.

Mechanical energy

Energy associated with movement, or scientifically the sum of kinetic (moving) energy and potential (stored) energy.

Megalitre (ML)

Used to measure liquids. One ML = one million (1,000,000) litres.

Megawatt (MW)

One MW = one thousand (1,000) kW or one million (1,000,000) watts.


A device that measures the amount of electricity used by a residence, business or equipment. Electric meters are typically calibrated in billing units, the most common one being the kilowatt-hour. Periodic readings of electric meters establishes billing cycles and energy used during a cycl


A colourless, odourless, flammable gas that is the main component of natural gas. It results from decomposition of certain organic matter, fossil fuel extraction and the process of digestion in animals (including humans).


Tiny living organisms that can cause fermentation, decomposition or disease.


A technique for purifying water, in which pressure is applied to force the liquid through a very fine barrier which removes undesirable materials.


The standard unit of storage capacity for a cell or battery. The milliamp-hour rating of a cell tells how many constant milliamps of current can be supplied by the pack for one hour. This rating can be used to find the duration a battery pack can provide, given a certain draw.

Nameplate capacity

The design-rated output of a generation plant in megawatts and standard operating conditions.

Natural gas

A colourless, combustible mix of hydrocarbon gases consisting mainly of methane (CH4). The gas may be extracted by either conventional or unconventional methods.

Network decentralisation

Generation of electricity from small energy sources that are close to the point of use, such as solar photovoltaic (PV) panels and cogeneration plants.

Network service provider

An owner, controller or operator of an electricity distribution or transmission system.

Newton's Third Law

Isaac Newton's Third Law states that for every action there is an equal and opposite reaction.

Non-renewable energy

Sources of energy that cannot be replaced when they have been used. Coal, natural gas and crude oil, all of which are fossil fuels, are examples of non-renewable energy sources.


Electricity that is provided during set times of the day when homes and businesses use a lot less electricity. To encourage people to use electricity during these times of the day, many providers offer cheaper electricity during these off-peak times.

Open cycle power station

A power station that operates only with a gas turbine, and is used to provide peak power, making it less energy-efficient but more flexible to turn on and off, than a combined cycle power station.


Any living animal, plant, bacterium or virus.

Ozone depletion

The reduction of ozone (O3) in the upper atmosphere as a result of human-produced chemicals, such as CFCs. Recent evidence suggests that ozone depletion in the upper atmosphere may affect climatic patterns on the earth's surface.


Electricity that is provided during set times of the day when demand for electricity is highest. Peak is also used to describe the highest demand for electricity which occurs on extreme hot or cold days. At these times, the power system is stretched to its limits.


Capable of being permeated (becoming diffused or saturated); in this instance, a material or membrane capable of having liquids or gases pass through it.


A legal permission allowing the holder to emit a defined quantity of greenhouse gases. In an emissions trading scheme, a permit is usually equivalent to one tonne of CO2e If a company emits less greenhouse gases than authorised, they can sell their permits within the trading scheme.

Petrol vehicle

A form of transport that is fuelled by petrol.


A liquid fuel made of hydrocarbons and other liquid organic compounds; refers to both naturally occurring unprocessed crude oils and petroleum products made of refined crude oil.


The process by which plants use energy from sunlight to turn carbon dioxide and water into organic compounds such as sugars, while giving off oxygen.

Potential energy

Stored energy.

Plugged and abandoned

A well, generally unsuccessful, which has been discontinued and plugged with cement.

Production well

A well drilled and the purpose of extracting light oil or natural gas from a reservoir.


Energy radiated or transmitted from a source as rays or waves in the form of tiny particles. Light, heat and sound are types of radiation.

Renewable energy

Energy that comes from sources that can be renewed or will never run out. This includes wind, sunlight, tides, gravity and geothermal heat.

Renewable energy certificates

Certificates issued by the Australian Government's Clean Energy Regulator. Retailers purchase a renewable energy certificate for each megawatt-hour (MWh) of electricity generated by government-accredited renewable electricity sources. Eligible sources include large-scale hydropower facilities and wind farms and also smaller scale generators, such as solar hot water and solar rooftop panels.


Origin uses reserves definitions consistent with those of the Society of Petroleum Engineers and required by the Australian Stock Exchange. Reserves reported are based on information compiled by full-time employees of the company who are qualified in accordance with Australian Stock Exchange listing rule 5.11. Proved plus probable (2P) reserves are those reserves which analysis of geologic and engineering data suggest are more likely than not to be recoverable under reasonable economic, technical and operating conditions.

Reverse osmosis

Breathing. The process of taking in oxygen (inhaling) and giving out (exhaling) carbon dioxide.


A technique for purifying water, in which pressure is applied to force the liquid through a very fine barrier which lets only the water molecules through.

Standby power

The electric power consumed by an appliance when it is not performing its primary function (i.e. microwave clocks or appliances turned off, yet able to be activated by remote control).

Stationary energy

A sector of the economy responsible for approximately half of all of Australia's greenhouse gas emissions; includes electricity generation, gas supply and fuels used directly in the manufacturing, construction and commercial sectors.


Electricity substations are part of the electrical system. They are located between the power generation plant and the consumer and perform functions such as transforming voltage from high to low (or vice versa).


A substance found in many plants, but extracted as ordinary sugar mainly from sugar cane or sugar beet.


Can be maintained at a stable level without draining natural resources or causing excessive harm to the environment.


The rate at which energy is charged. One component of the tariff is the fixed energy supply charge, which is the cost associated with supplying electricity to a home. The second component is variable cost, based on how much energy a consumer has used over the billing period.

Tidal power

Energy derived from the ebb and flow movement of the tides which turns turbine blades to create electricity.


A pricing contract with a retailer in which a customer is charged a different price according to when they use energy. This normally involves peak and off-peak pricing, which means the customer is charged less if they use energy during a period of low demand, such as night time.

Traditional meters

Meters that are not digital but instead use a mechanical spinning metal disk to measure the accumulated amount of electricity used.


Equipment that is used to either increase or decrease electricity voltage.


The movement of electricity along transmission lines once it leaves the power station. The transmission lines deliver the electricity, often over long distances, to distribution networks in urban areas.


The production of electricity, heating and cooling from a single power source.


Any type of machine in which the energy of a moving fluid (water, air or steam) is converted into mechanical energy by making a blade rotate.

Unconventional gas

Natural gas that is not found in permeable sandstone reservoirs as is the case for conventional gas. Coal seam gas (CSG) is found in coal deposits, usually 200 to 1,000 metres below the ground. Shale gas is found in shale rock deposits and the wells to extract this gas are generally a lot deeper than CSG wells.


A unit used to measure the electric field strength or force that moves electric current through a circuit.

Watt (W)

A measure of power present when a current of one ampere flows under the pressure of one volt. One watt represents the expenditure of one joule of energy per second.

Wave power

A renewable source of energy based on harnessing the movement of ocean waves to generate electricity.

Wholesale electricity market

A market in which electricity is bought and sold, such as the National Electricity Market (NEM).

Wind energy

Energy from air flowing over the earth's surface used to create electricity. The energy of the wind turns blades of a wind turbine that’s connected to a generator, converting the kinetic energy of the wind to electricity.