| 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 |



This is the procedure in which an authoritative party provides formal recognition that a body is technically competent and impartial to carry out certain tasks such as tests, certifications, etc.

Acid Rain

This is rain that contains harmful amounts of sulfuric and nitric acids, which are formed by sulfur oxides and nitrogen oxides being released into the atmosphere when fossil fuels are burned. Acid Rain can be in the form of wet precipitation (rain, fog, or snow) or dry precipitation (dust, absorbed gaseous and particulate matter, and aerosol particles). pH for Acid Rain is below 5.6. (pH value measures alkalinity and acidity, ranging from 0 to 14. 7 is considered to be neutral. Below 7 indicate increased acidity whereas above 7 indicates increased alkalinity; "Acid Precipitation" or "Acid Deposition"

Activation Energy

The amount of energy that is required to start a reaction

Active Heating System

Space-heating or solar water system that uses fans/pumps to move heated water or air.


This means that a carbon offset project is beyond normal business. This can be used to determine which projects would have been built without the incentive of a carbon market.


Entity that negotiates bulk energy for a group of consumers (known as a buying group).


This is the dehumidifying and cooling of air that is within a building through a refrigeration unit that is either powered by natural gas or electricity. This does not include the evaporative cooling systems (swamp coolers), fans or blowers that are not connected with the refrigeration unit.

Alternating Current

Electric current that reverses direction in regular recurring intervals.

Alternative Fuel

"Non-Conventional" transportation fuels that are made with either biomass materials (methanol, ethanol) or natural gases (compressed natural gas, methanol, propane, etc).

Alternative-Fuel Vehicle (AFV)

This is a vehicle that operates on Alternative Fuel. Such a vehicle is made to run exclusively on alternative fuel and can also be designed to run on traditional fuel.

Amorphous Module

These are modules that are made with Amorphous Silicon (a-Si), which is the non-crystalline form of silicon. It is the cheapest basis of solar cells, however, it has the lowest efficiency of electricity production.

Amorphous Silicon

Amorphous silicon is the non-crystalline form of silicon and was the first thin film material to yield a commercial product, first used in consumer items such as calculators. It can be deposited in thin layers onto a variety of surfaces and offers lower costs than traditional crystalline silicon, though it is less efficient at converting sunlight into electricity.


A unit of measure for electrical current; Amount of current that flows in a circuit at a resistance of one Ohm and an electromotive force of one Volt. Abbreviated as Amp.

Annual Consumption

Amount of electricity used by a consumer in one year, usually measured in kWh (kilowatt-hours).

Annual Report

Reports that have to be accurate in informing a particular company's performance.

Annualized Growth Rates

This can be calculated as
(xn/x1) * 1/n
x is the value under consideration; n is the number of periods; * means to multiply


Entity applying for provisional certification


This is a subsurface rock unit that can produce water.

Availability Factor

This is a percentage that represents how many hours a generating unit is available to produce power, regardless of the amount of power, within a period of time, compared to the number of hours within the period.

Avoided Costs

These are the incremental costs of capacity and/.or energy that a utility would incur on itself with the generation of energy or purchase from another source. It does not include the purchase from a qualifying facility.


This is the deviation of a solar panel's position from a north-pointing direction; measured clockwise from the north.
Azimuth of 0 degrees: Panel points exactly north
Azimuth of 180 degrees: Panel points south and provides the highest yield
Azimuth of 135 degrees: Panel points in South-Eastern direction
Azimuth of 225 degrees: Panel points in South-Western Direction