GBI

Green Building Initiative: a not for profit organization whose mission is to accelerate the adoption of building practices that result in energy-efficient, healthier and environmentally sustainable buildings by promoting credible and practical green building approaches for residential and commercial construction. They are the developers of the Green Globes building rating system (see Green Globes).

Geotextile

Cloth or clothlike material intended for use in the soil, usually for filtering or containing soil water. Some types are used to prevent or control erosion.

Geothermal heat

Relating to the internal heat of the Earth. The water of hot springs and geysers is heated by geothermal sources. Geothermal and groundsource heat are easily confused (see Ground source heat pump).

GIS

Geographical Information System: detailed information on the soils, hydrology, land use patterns, and plant and animal habitats of sites, plotted on maps or entered in databases and employed to evaluate appropriate location of buildings and infrastructure, and to plan landscaping and other land use considerations.

Glare

The effect produced by luminance within one's field of vision that is sufficiently greater than the luminance to which one's eyes are adapted; it can cause annoyance, discomfort, or loss in visual performance and visibility.

Glazing

Transparent or translucent coverings which allow light to enter rooms and solar collectors while providing weather protection. Window glass and clear plastic films are examples of glazing.

Global Green

Global Green USA is a national non-profit, non-partisan environmental organization addressing three of the greatest challenges facing humanity: Stemming global climate change by creating green buildings and cities; Eliminating weapons of mass destruction that threaten lives and the environment; and Providing clean, safe drinking water for the 2.4 billion people who lack access to clean water. President Mikhail Gorbachev founded the organization in order to create a new approach to solving the world's most pressing environmental challenges by reconnecting humanity to the environment.

Global warming

A gradual, long-term increase in the near surface temperature of the earth. Global warming has occurred in the distant past as the result of natural influences, but the term is most often used to refer to the warming predicted to occur as a result of increased emissions of greenhouse gases. Scientists generally agree that the earth's surface has warmed by about 1 degree Fahrenheit in the past 140 years. The Intergovernmental Panel on Climate Change (IPCC) recently concluded that increased concentrations of greenhouse gases are causing an increase in the earth's surface temperature and that increased concentrations of sulfate aerosols have led to relative cooling in some regions, generally over and downwind of heavily industrialized areas.

Golden Section/Ratio/Rule/Rectangle

A ratio that emulates proportions found in nature. At least since the Renaissance, many artists and architects have proportioned their works to approximate the golden ratio. A golden rectangle is a rectangle whose side lengths are in the golden ratio 1:1.618. A distinctive feature of this shape is that when a square section is removed, the remainder is another golden rectangle, that is, with the same proportions as the first. Square removal can be repeated infinitely, which leads to an approximation of the golden spiral. 

Graywater

Water that has been used for showering, clothes washing, and faucet uses. Kitchen sink and toilet water is excluded. This water can be reused in subsurface irrigation for yards (often spelled greywater).

Green building

An integrated framework of design, construction, and operational practices that encompasses the environmental, economic, and social impacts of buildings. Green building practices recognize the interdependence of the natural and built environments and seek to minimize the use of energy, water, and other natural resources, minimize site impact, and provide a healthy, productive indoor environment.

Green collar job

A job connected to eco-friendly products and services. Examples are recycling operations, alternate (renewable/sustainable) energy sources, clean technology, and construction via green building, organic farming, solar panel production and installation, bicycle repair. By definition and nature, green jobs are local job market area positions. Because of this, green jobs can create employment opportunities for previously unemployed or underemployed people and remove them from public assistance roles. They boost local economies by keeping dollars spent at home.

Green design

A design, usually architectural, conforming to environmentally sound principles of building, material and energy use. A green building, for example, might make use of solar panels, skylights and recycled building materials.

Green development

A development approach that goes beyond conventional development practice, by integrating the following elements: Environmental responsiveness—Benefiting the surrounding environment; Resource efficiency—Using resources in the construction, development, and operations of buildings and/or communities in ways that are not wasteful; and Sensitivity to existing culture and community—Fostering community in design, construction, and operations. Bringing these elements together through the green development approach provides numerous environmental and economic benefits by capitalizing on the interconnections.

Greenfield

Undeveloped land.

Green Globes

An online building and management environmental audit which helps property owners and managers measure the environmental performance of their buildings against best practices in areas such as energy, water, hazardous materials, waste management and indoor environment. It is both a guide for integrating green design principles and an assessment protocol. The rating system has seven categories adding up to 1,000 points. One Green Globe = 350 points, 550 = two Green Globes, 700 = three Green Globes, and 850 = four Green Globes. (See GBI).

Greenguard Environmental Institute

The mission of Greenguard Environmental Institute (GEI) is to improve public health and quality of life through programs that improve indoor air. In accordance with that mission, GEI currently has three third-party certification programs for Indoor Air Quality, Children & Schools, and Building Construction.

Greenhouse effect

The warming of the Earth's atmosphere attributed to a buildup of carbon dioxide or other gases; some scientists think that this build-up allows the sun's rays to heat the Earth, while making the infra-red radiation atmosphere opaque to infra-red radiation, thereby preventing a counterbalancing loss of heat.

Greenhouse gas

Any of several dozen heat-trapping trace gases in the earth's atmosphere which absorb infrared radiation. The two major greenhouse gases (GHG’s) are water vapor and carbon dioxide; lesser greenhouse gases include methane, ozone, CFCs, and nitrogen oxides.

Green Label

A certification program by the Carpet and Rug Institute (CRI) for carpet and adhesives meeting specified criteria for release of volatile compounds.

Green power

Power derived from renewable energy sources such as solar, wind, geothermal, bio-mass, or low-impact hydro sources.

Green roof

(See ecoroof).

Green Seal

A widely recognized green product certification. The Green Seal organization is "an independent, non-profit organization that strives to achieve a healthier and cleaner environment by identifying and promoting products and services that cause a less toxic pollution and waste, conserve resources and habitats, and minimize global warming and ozone depletion. Green Seal has no financial interest in the products that it certifies, or recommends, or in any manufacturer or company."

Green street

Landscaped stormwater curb extensions that reduce the negative impacts of stormwater runoff. The stormwater is managed on the surface and at its source.

Green tag

Also known as a Renewable Energy Certificate (REC), Renewable Energy Credit, or Tradable Renewable Certificate (TRC), are the property rights to the environmental benefits from generating electricity from renewable energy sources. These certificates can be sold and traded and the owner of the REC can legally claim to have purchased renewable energy. While traditional carbon emissions trading programs promote low-carbon technologies by increasing the cost of emitting carbon, RECs incentivize carbon-neutral renewable energy by providing a subsidy to electricity generated from renewable sources. In states with a REC program, a green energy provider (such as a wind farm) is credited with one REC for every 1,000 kWh of electricity it produces (for reference, an average residential customer consumes about 800 kWh in a month). A certifying agency gives each REC a unique identification number to make sure it doesn't get double-counted. The green energy is then fed into the electrical grid (by mandate), and the accompanying REC can then be sold on the open market.

Green wash

To falsely claim a product is environmentally sound. Also known as faux green. Disinformation disseminated by an organization so as to present an environmentally responsible public image.

GRI

Global Reporting Initiative: a multi-stakeholder process and independent institution whose mission is to develop and disseminate globally applicable Sustainability Reporting Guidelines. These Guidelines are for voluntary use to report on the economic, environmental, and social dimensions of an organization’s activities, products and services.

Ground Cover

Low-growing plants often grown to keep soil from eroding and to discourage weeds.

Ground source heat pump

This system uses underground coils filled with water to capture heat from the ground and transfer it to the inside of a building; they do not generate heat, but capture it from the earth (compared with geothermal heat which is renewable energy). This type of heat pump can realize substantial energy savings over conventional heat pumps, by using the naturally more stable temperature of the earth as its heat source. Also known as geo-exchange, geothermal and geoX (see heat pump). It can be confused with “geothermal heat” which refers to the renewable energy source of heated ground water. (see Geothermal heat).

GWP

Global Warming Potential: the ratio of the warming caused by a substance to the warming caused by a similar mass of carbon dioxide. CFC-12, for example, has a GWP of 8,500, while water has a GWP of zero.