Term and Description

Symbol or Abbreviation

A or A B C D E F G H I J K L M N O P Q R S T U V W X Y Z or Subject Areas or Top

acid rain

Acids (sulphurous, sulphuric, nitrous and nitric acids) can form in the atmosphere as a result of moisture in the air mixing and reacting with:

sulphur oxides (SOx) (from burning fossil fuels which contain sulphur. The sulphur content of fuels varies, with North American coals and crude oil having a higher sulphur content than most Australian supplies).

nitrogen oxides (NOx), mainly from burning of fossil fuels and wood

Acid rain is the general term for the deposition of this acid onto buildings, vegetation etc, either:

 

• wet, in rain, mist, snow, etc, or

dry, as salts.

Acid rain damages buildings and other structures (especially metal and stone) weakens or kills terrestrial and aquatic plants and fish , and degrades the health of people and animals.

Because SOx and NOx are gases and because the formation of acid rain takes time, acid rain damage often occurs far from the source of the problem.

active (building design feature or energy system.

Active features are those with moving parts and/or controls such as fans, pumps and automated blinds or louvres. For example, a solar hot water system which uses a pump to circulate water through the collector is classified as active while one relying on natural the thermosiphon effect is classified as a passive system.

aerobic

Refers to processes which occur in the presence of oxygen (because the process needs oxygen).

This contrasts with anaerobic processes.

See also greenhouse gases

aerosols (in the atmosphere)

Very small particles and droplets, excluding water, dispersed in the atmosphere. Aerosols absorb solar radiation, then re-emit and scatter it, and so have a net cooling effect. Aerosols also they facilitate the process by which water vapour turns into cloud droplets.

The main human-activity source of aerosols in the atmosphere is sulphur dioxide: chemical reactions convert it into sulphate aerosol.

see also Subject Area greenhouse effect

afforestation.

Creating a forest(s) where there was not one before. This can be used to act as a greenhouse gas sink, and to provide timber as an alternative to destroying existing forests.

see also deforestation, and Subject Area: greenhouse response

albedo

the reflection of solar radiation which falls on the earth back into space.

alternating current

AC

anaerobic

Refers to processes which are caused by the action of anaerobes which are micro-organisms which require or can survive in an oxygen-free environment.

Methane is created by the anaerobic decomposition of organic material.

Anaerobic is the opposite of aerobic.

anthropogenic

Caused by the human race or human activities.

Normally used in the context of "anthropogenic greenhouse effect" ie. the human addition to the natural greenhouse effect.

see also: greenhouse effect

aromatics

Hydrocarbons with a ring structure, generally with a distinctive aromatic odour, and good solvent properties, sometimes used as octane improvers in petrol.

e.g. benzene, toluene and xylene

atmosphere

B or A B C D E F G H I J K L M N O P Q R S T U V W X Y Z or Subject Areas or Top

ballast

An electrical device in a fluorescent or other discharge light fitting which acts to limit the electrical current in the lamp.

barrel (of oil)

A standard measure for oil and oil products.

One barrel = 159 litres.

(bbl)

barrel oil equivalent

The amount of energy equivalent to a barrel of oil, used to describe other energy sources such as natural gas, petroleum gas, etc..

One boe = 6.12 GJ

See also measurement and energy and power measurements

(boe)

base load

the minimum system load where the load varies, especially the overnight minimum load in a system.

Electricity Systems. State electricity systems display a base-load which can be around 60% to 75% of the daily maximum. To serve the varying load, electricity generation systems are normally designed to include

 large coal-fired "base-load" power stations which are economical to run but which are not suited to short runs.

 intermediate-load power stations, typically large gas-fired boilers and steam turbines, and

 peak-load power stations, typically gas turbines (which are similar to aircraft jet engines) fuelled by natural gas.

Electricity utilities have adjusted tariffs to encourage electricity use during the off-peak periods (see also demand side management) with special low prices for off-peak water heating (which unfortunately wastes energy both from unavoidable standing losses in a storage heating system and the built-in losses in the electricity generation and reticulation system). From a greenhouse gas perspective, the encouragement of electricity for water heating is also regrettable because of the very high emissions compared with natural gas, LPG, and solar alternatives.

Customer Load Profiles. The pattern of energy consumption for a building, factory or other customer premises will also often display a base-load, even for those customers with no apparent need for energy outside working hours. Monitoring energy consumption and finding this base-load often reveal significant opportunities to reduce energy related greenhouse gas emissions and costs. In fact, it is not unusual for a business to consume as much energy outside working hours than during working hours (especially for businesses with relatively short business hours (2000 working hours per year leaves 5760 non-working hours per year).

see efficiency, system efficiency, standing losses, and Subject area: efficiency

benchmarking, performance indicators

establishment of a quantitative reference point by which efficiency, performance or excellence can be judged and progress monitored. The benchmark will often use a parameter which will allow comparison of performance with other organisations in a similar role. For example, these may be CO₂ per $ turnover, per room night, per tonne of product, per square meter or floor space, per meal served, etc.

see also Subject area: efficiency

biomass (energy)

Term to describe the resource of energy stored in plants and animals or released during their use or processing including as a by-product or "waste". Examples include:

 wood, for heating

 bagasse (sugar cane residue) for raising steam which is used in sugar refining and for the generation of electricity which can be exported from the sugar mill to the grid.

 residue from agricultural products, eg. straw.

 methane, generated from the anaerobic decomposition of animal and plant wastes, including vegetable peelings, manure, either collected from purpose built digesters or as land-fill gas.

 dung.

 tallow.

Biomass is a renewable energy source and the main source of stored energy for the majority of the human race.

See also: ethanol, methanol, and Subject area energy sources.

biosphere

The system comprising the earth and its atmosphere, which supports life.

boiler

 a device for heating water to convert it to steam for use in heating or power generation, etc.

 also used to describe a large commercial water heater in which the water does not boil (these should really be called water heaters). Such heaters are commonly used for comfort heating in large air-conditioning systems in office building. The term atmospheric boiler is also used to describe these, because the water stays at atmospheric pressure.

British Thermal Unit

Imperial unit of energy equal to 1.055 kJ (kiloJoules).

Derivation and definition: the amount of heat necessary to raise one (1) pound of water, one (1) degree Fahrenheit.

see also: Energy and Power Measurement

BTU

Brundtland Commission.

The informal name used for the World Commission on Environment and Development (WCED), established in 1984 by the UN General Assembly, and chaired by Norwegian Prime Minister Gro Harlem Brundtland. The Commission's report: Our Common Future (1987), established the concept of sustainable development.

bunkers (fuel use)

energy used for international marine and air transport tasks.

business as usual

An economic "base-case" where no actions are taken specifically because of their greenhouse abatement benefits (although they may be undertaken because of their other benefits; eg. cost savings).

see also: greenhouse response

C or A B C D E F G H I J K L M N O P Q R S T U V W X Y Z or Subject Areas or Top

calorific value:

also referred to as "Heat Value or Heat of Combustion". The amount of energy released from a substance when it is completed converted to heat energy, usually involving a change in chemical composition.

The heat value can be described as:

Gross calorific value, which includes the heat available from the products of combustion as they are cooled to ambient temperature. The GCV is also called the higher heating value.

Net calorific value (NCV) is the gross calorific value less the heat required to vaporise the fuel before it can be burnt and to vaporise water vapour produced during combustion (this energy is normally supplied by the fuel during the combustion process, but in a laboratory test can be supplied by an external heat source.

see also Subject Areas: energy sources, and measurement

GCV

NCV

Carbon dioxide

The main greenhouse gas and the gas to which other greenhouse gases are compared. Most of the increase in CO₂ concentration in the atmosphere is attributable to:

 increasing the source of CO₂ by burning fossil fuels and so releasing carbon which has been previously stored out of the atmosphere, and

 reducing the capacity of the earth to remove CO₂ from the atmosphere by destroying forests (see carbon sinks).

Human activities add about 26 Gigatonnes (26 billion tonnes) of CO₂ to the atmosphere every year.

See also: energy sources and CO2 emissions, and other greenhouse gases

CO₂

Carbon dioxide equivalent

The amount of carbon dioxide to achieve the same contribution to the enhanced greenhouse effect as a given amount of another gas. This enables all emissions to be tallied to arrive at a single total.

According to Australia's 1990 greenhouse gas inventory, 572 million tonnes of carbon dioxide equivalent emitted per year.

See also Global Warming Potential, greenhouse gases,

CO_{2 equiv}

Carbon dioxide fertilisation.

Improved plant growth as a result of increased concentrations of CO₂ in the atmosphere

Carbon intensity

The amount of CO₂ emitted for each unit of product (eg. tonne of manufactured product, GWh of electricity, dollar of value added).

See also: Energy Sources and CO2 Emissions

Carbon leakage

A term given to a hypothetical increase in emissions as a result of movement of production from an efficient country to a less efficient country, after the former introduces emission reduction initiatives which (again, hypothetically) increase the cost of production.

If this did occur, the nett global effect of the abatement action one country would be an increase in greenhouse gas emissions. However, given the wide range of emission reduction strategies which actually reduce the cost of production, this theory is not very compelling.

See also: greenhouse effect

Carbon monoxide

A precursor of ozone.

See also: greenhouse gases

CO

Carbon sink

A way of removing carbon from the atmosphere, including natural mechanisms such as photosynthesis in trees (CO₂ to wood) and calcium carbonate (CaCO₃) formation by marine molluscs.

See also: greenhouse response

Carbon source.

A pool or store of carbon.

chlorofluorocarbons

Man-made chemical compounds containing chlorine, fluorine and carbon. Specific compounds within this family are each given suffix (e.g. CFC-11, CFC-12). CFCs are relatively inert, non-toxic but contribute to two major environmental problems:

 EnhancedGreenhouse Effect..

 Ozone Depletion.

CFCs are powerful greenhouse gases. This, combined with their long life in the atmosphere (around 50 years, because of their inertness) would make them a problem, however they also destroy ozone in the lower stratosphere, which tends to negate their direct greenhouse effect. Also, because they are the main cause of damage to the ozone layer, their use is being curtailed by the Montreal Protocol. The most common uses of CFCs have been as:

 propellants (in aerosol cans or "pressure packs")

 refrigerants (in air-conditioners and refrigerators),

 blowing agents for producing foam products, such as expanded polystyrene insulating panels, disposable cups, etc.

The use of prescribed CFCs in Australia is legal, but the manufacture and importation is banned. The use of CFCs is declining as equipment which relies on these compounds is replaced or modified. Because of the supply restrictions, the price of CFCs has sky-rocketed and so most users are getting a clear economic signal to replace CFC-based equipment.

see also fluorocarbons, Montreal Protocol, and the Subject Area:greenhouse gases

CFCs

Climate Change (FCCC usage)

A change of climate which is attributed directly or indirectly to human activity which alters the composition of the global atmosphere and which is in addition to the natural variability observed over comparable time periods.

see also: greenhouse effect

Climate Change (IPCC usage)

Climate change as referred to in the observational record of climate occurs because of internal changes within the climate system or in the interaction between its components, or because of changes in external forcing, either for natural reasons or because of human activities. It is generally not possible clearly to make attribution between those causes. Projections of future climate change reported by IPCC consider only the influence on climate of anthropogenic increases in greenhouse gasses and other human-related factors.

see also: greenhouse effect

Climate System (FCCC usage)

the totality of the atmosphere, hydrosphere, biosphere and geosphere and their interactions

Source UNFCCC, Climate Change Secretariat, Definitions

coal (CO₂ emissions)

see: emission figures for briquettes and electricity

cogeneration,

Combined heat and power generation where both the heat and motive power or electricity outputs are put to use. This compares with electricity generation in a power station where the unavoidable heat generated usually can not be profitably employed and so is wasted.

Also called "combined heat and power" or "CHP".

see also: Subject Area energy sources

(CHP)

compact fluorescent lamps

a fluorescent which is smaller than the original fluorescent lamps and their derivatives. Compact fluorescent lamps:

 have power ratings from 5 Watts to 55 Watts (the latter is 535 mm long; which is not really compact but is smaller than the equivalent standard fluorescent lamp which would be 1500 mm long).

 normally use tri-phosphor coatings, which gives them a more acceptable light colour and higher efficiency than standard lamps.

 may either have an integral ballast (allowing them to be used as drop-in replacements for incandescent lamps) or rely on a ballast which is hard-wired into the light fitting.

CFLs

compressed natural gas

Natural Gas which has been compressed to allow a useful amount of energy to be stored in the limited space available in a vehicle fuel tank. The advantages of CNG for vehicles are that it burns cleaner than petrol, is cheaper than petrol, and uses a wholly indigenous fuel source. The CO₂ emissions of natural gas energy use are about 10% lower than for petrolbut this excludes the electricity used to compress the natural gas, which increases both the energy used and the CO₂ emitted.

also called Natural Gas for Vehicles (NGV).

CNG

NGV

conduction

heat transfer through a material which does not rely on movement of the material..

see also: convection and radiation

Conference of the Parties

The Conference of the Parties under the FCCC, at its first meeting in Berlin (1995), initiated a negotiation over a protocol, or other legal instrument, to include quantified emission objectives beyond the year 2000, and coordinated policies and measures. Further, the Second Conference of the Parties (Geneva, 1996) called for the inclusion of legally-binding quantified objectives in the legal instrument to be negotiated at Kyoto in December 1997.

convection

heat transfer by the movement of fluids (liquids and gases) containing heat energy.

see also: conduction and radiation

conversion efficiency

the efficiency in of the energy conversion process.

conversion (of energy)

see energy conversion

cooling degree-days

see degree-days

cultural change

Changing peoples human knowledge, learning methods, shared attitudes, values, goals, beliefs, social norms, practices and behaviours in an organisation or corporation to better meet the goals of the organisation and the wider community.

see also: Subject Area: greenhouse response

current

In an electrical circuit, the flow of electricity, measured in Amps.

See description in Electrical Measurements and Terms

I

D or A B C D E F G H I J K L M N O P Q R S T U V W X Y Z or Subject Areas or Top

deforestation.

Loss of forest, usually as the result of clearing for agricultural (especially for cattle grazing) or other land uses such as roads and buildings.

Estimated (Source: Mintzer, 1992).deforestation causes worldwide are:

 slash and burn timber gathering, 40-50%

 grazing 10%,

 10-20%,

 forestry and plantations for 5-10%, and

 forest fires 1% to 15%.

Deforestation destroys what may be an important sink for excess CO₂ in the atmosphere.

Although afforestation is promoted as a way of taking CO₂ from the atmosphere, reducing or stopping deforestation is a much cheaper and achievable strategy, which also has the advantage of preserving a greater diversity of plant and animal species.

see land use CO₂ emissions in the summary of the Australian greenhouse gas inventory

degree-days

a measure of the demand for heating ("heating degree-days") or cooling heating ("cooling degree-days") in a geographical location, expressed as degree-days per year to a base temperature. One degree-day means that the temperature needed to be changed by an average of 24 degree-hours during the year. For example, the Melbourne heating demand to base 18° C is 1378 heating degree-days per year; the figure for Brisbane is 238, and for Darwin 0. Programs are available to calculate the heating and cooling degree-days for periods other than continuous operation (eg. during office hours only).

demand-side management (DSM).

Usually taken to mean managing the demand for electricity to enable existing generation and transmission assets to meet customer requirements, rather than simply building more power stations etc. The maximum demand can be managed, for example, by:

 fuel switching (eg. from electricity to gas),

 using more efficient appliances,

 time-shifting loads (eg special tariffs for irrigators who pump outside the peak demand periods) which flattens the load demand profile without reducing total electricity use.

DSM has several advantages over increasing energy supply:

 most DSM methods reduce greenhouse gas emissions whereas boosting energy supply leads to increases,

 most DSM actions have a higher return on investment,

 reductions can be implemented in small increments, resulting in lower financing requirements and risks than increasing energy supply,

 they have a much shorter lead time,

 DSM actions typically use local resources and labour, whereas power stations typically use imported turbines, generators and controls, etc.

DSM has been hampered in the past by insufficient use of integrated resource planning and life cycle costing.

see also: base load

DSM

diesel engine,

An internal combustion engine which uses heat and compression of the fuel air mixture to cause the mixture to ignite (hence diesel engines are also referred to as "compression ignition" engines).

Diesel engines:

 have a higher fuel efficiency than petrol engines

 must be made stronger than petrol engines in order to withstand the stress caused by "diesel knock" and so are heavier and more expensive to produce, but last longer.

 emit particulates in the exhaust; these have been associated with health problems including cancer.

diesel fuel

Fuel which as a fuel-air mixture which will spontaneously ignite in a diesel engine because of the heat and compression.

CO₂ emissions: see: energy sources and CO2 emissions

direct current

An electrical system where the flow of electricity does not change its direction.

See description in Electrical Measurements and Terms

DC

direct greenhouse gas:

see greenhouse effect

discount rate

a reduction in the value of future cash flows because of the time-value of money.

see also: financial evaluation

E or A B C D E F G H I J K L M N O P Q R S T U V W X Y Z or Subject Areas