Additionality

Emissions reductions are additional if they occurred because of funding through carbon credits and would not have occurred otherwise

Afforestation

Establishing a forest on land that is not a forest, or has not been a forest for a long time by planting trees or their seeds.

Alternative Energy 

Renewable sources of power not derived from burning hydrocarbons, which emit less (or no) greenhouse gas.  "Old renewables" include nuclear and less (or no) greenhouse gas.  "Old renewables" include nuclear and hydroelectric power, "new renewables" include solar and wind power

Carbon Dioxide (CO2)

A colorless, odorless gas produced by animal respiration, the decay of plant or animal remains and the burning of fossil fuels.  Of the six principal greenhouse gases, CO2 is the one most directly affected by human activity

Carbon Footprint

The amount of CO2 created by all activities within a given sphere, a person's daily life, a city, a manufacturing process, etc.

Carbon Neutral 

The means for individuals and corporations to neutralize their GHG emissions by set standards and offsets through carbon credits

Certificate of Emissions Reductions 

A certificate reflecting the reduction or avoidance of one ton of CO2e

Emissions

The release of substances, such as greenhouse gases, into the atmosphere.  Emissions caps are legal limits on how much greenhouse gas a business, city or nation can emit

GHG 

Greenhouse gas, the primary gases (both naturally existing and man made) that contribute to global warming by trapping more energy in the earth’s atmosphere than would occur in their absence.  Greenhouse gases covered by the Kyoto Protocol are:  Carbon Dioxide (CO2), Methane (CH4), Nitrous Oxide (N2O), Sulfur Hexafluoride (SF6), Hydro fluorocarbons (HFC’s), and Pefluorocarbons (PFC’s)

Gold Standard 

An offset standard based on the Kyoto Protocols clean development mechanism and developed by several international non-profit organizations.  This standard certification is for renewable energy efficiency projects

Kyoto Protocol 

An internationally binding agreement that falls under the more general United Nations Framework Convention and Climate Change (UNFCCC).  The Protocol sets GHG targets for countries that sign and ratify the agreement.  Even though the United States has not ratified the agreement, the United States is responsible for 25% of the world's hydrocarbon emissions and has a voluntary program.  States and municipalities are putting legislation in effect to meet the Kyoto Protocol guidelines

LEED Certification (Leadership in Energy and Environmental Design)

The main route to certifying a green building.  This includes new building construction and major renovation projects. LEED certified buildings enjoy government incentives, marketing benefits, increased property values and lower utility/energy costs.

MWh
1 Megawatt = 1000 KW or 1,000,000 watts.  One megawatt is enough electrical energy to power 1000 average homes.

Reforestation
Restoring and recreating areas of woodlands or forest that once existed but were deforested or otherwise removed or destroyed in the past.

Renewable Energy Certificate

A certificate that represents the environmental attributes of 1 MWh of electricity from a renewable energy source

Sinks

A natural reservoir that withdraws and traps a pollutant.  Soil and plants act as carbon sinks, for instance

White Tag

A certificate equivalent to 1 MWh of energy savings