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An introduction to energy resources

S278_2 Glossary

S278_2 Glossary.
Browse the glossary using this index

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Conditions that are oxygen poor (lacking oxygen). Not all the fixed carbon in dead plant tissue returns to the atmosphere as CO2: some may be retained as carbon-enriched residue and yet more converted into hydrocarbons.
Permalink: Anoxic



Wood and other plant materials that can be used as fuels.
Permalink: Biomass



Organic compounds of carbon, hydrogen and oxygen, with the general formula CnH2nOn. Glucose, one of the simplest carbohydrates, has the formula C6H12O6.
Permalink: Carbohydrates

Carbon cycle

The movement of carbon between the major natural stores of carbon (called ‘reservoirs’) on the Earth. The two major divisions of the cycle are the terrestrial and marine carbon cycles.
Permalink: Carbon cycle



The capacity to do work, measured in joules (J).
Permalink: Energy

Energy density

The amount of energy stored by a resource relative to the volume that it occupies.
Permalink: Energy density

Energy efficiency

The ratio of the useful output of work to the input of energy supplied — usually expressed as a percentage.
Permalink: Energy efficiency


The total energy content of a physical system.
Permalink: Enthalpy



The means by which the direction or speed of movement of an object is changed; equal to mass x acceleration.
Permalink: Force

Fossil fuels

Combustible resources derived from ancient organisms, especially coal, oil and natural gas.
Permalink: Fossil fuels

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