Glossary of Green Terminology

Acid Rain:
A term used to describe precipitation that has become acidic (low pH) due to the emission of sulfur oxides from fossil fuel-burning power plants. Source: U.S. Department of Energy / Office of Energy Efficiency and Renewable Energy
Alternative Fuels:
Alternative fuels are derived from resources other than petroleum. Some are produced domestically, reducing dependence on foreign oil, and some are derived from renewable sources. Often, they produce less pollution than gasoline or diesel. Source: U.S. Department of Energy / Office of Energy Efficiency and Renewable Energy
Appliance Energy Efficiency Ratings:
The ratings under which specified appliances convert energy sources into useful energy, as determined by procedures established by the U.S. Department of Energy. Source: U.S. Department of Energy / Office of Energy Efficiency and Renewable Energy
Biodiesel is an alternative fuel made from virgin vegetable oil or used vegetable oil. Even animal fats like beef tallow and fish oil can be used to make biodiesel fuel. Biodiesel may be blended with conventional diesel to get different blends such as B2 (2 percent biodiesel and 98 percent conventional diesel) or B20 (20 percent biodiesel) or it can be used as 100 percent biodiesel (B100). Source: U.S. Environmental Protection Agency
Biofuels are any fuel derived from biomass. Agricultural products specifically grown for conversion to biofuels include corn and soybeans. R&D is being conducted to improve the conversion of non-grain crops, such as switchgrass and a variety of woody crops, to biofuels. The energy in biomass can be accessed by turning the raw materials of the feedstock, such as starch and cellulose, into a usable form. Transportation fuels are made from biomass through biochemical or thermochemical processes. Known as biofuels, these include ethanol, methanol, biodiesel, biocrude and methane. Source: U.S. Department of Energy / Biomass Program
Biomass is any organic material made from plants or animals. Domestic biomass resources include agricultural and forestry residues, municipal solid wastes, industrial wastes, and terrestrial and aquatic crops grown solely for energy purposes. Biomass can be converted to other usable forms of energy and is an attractive petroleum alternative for a number of reasons. First, it is a renewable resource that is more evenly distributed over the Earth's surface than are finite energy sources, and may be exploited using more environmentally friendly technologies. Agriculture and forestry residues, and in particular residues from paper mills, are the most common biomass resources used for generating electricity and power, including industrial process heat and steam, as well as for a variety of biobased products. Use of liquid transportation fuels such as ethanol and biodiesel, however, currently derived primarily from agricultural crops, is increasing dramatically. Source: U.S. Department of Energy / Biomass Program
Carbon Dioxide:
A colorless, odorless noncombustible gas with the formula CO2 that is present in the atmosphere. It is formed by the combustion of carbon and carbon compounds (such as fossil fuels and biomass), by respiration, which is a slow combustion in animals and plants, and by the gradual oxidation of organic matter in the soil. Source: U.S. Department of Energy / Office of Energy Efficiency and Renewable Energy
Carbon Footprint:
A carbon footprint is a measure of the impact human activities have on the environment in terms of the amount of greenhouse gases produced, measured in units of carbon dioxide. Source: Carbon Footprint
Chlorofluorocarbon (CFC):
A family of chemicals composed primarily of carbon, hydrogen, chlorine and fluorine whose principal applications are as refrigerants and industrial cleansers and whose principal drawback is the tendency to destroy the Earth's protective ozone layer. Source: U.S. Department of Energy / Office of Energy Efficiency and Renewable Energy
Circulating Fluidized Bed Combustion Technology (CFB):
A type of furnace or reactor in which the emission of sulfur compounds is lowered by the addition of crushed limestone in the fluidized bed, thus obviating the need for much of the expensive stack gas clean-up equipment. The particles are collected and recirculated, after passing through a conventional bed, and cooled by boiler internals. CFB technology is recognized by the U.S. Department of Energy as a clean-coal technology. CFB technology has strong environmental performance, and a record of dependable, cost-effective service. CFB boilers are very flexible and can utilize a wide range of fuels, including run of mine coal, waste coal and biomass. Source: U.S. Department of Energy Office of Energy Efficiency and Renewable Energy
Clean Power Generator:
A company or other organizational unit that produces electricity from sources that are thought to be environmentally cleaner than traditional sources. Clean, or green, power is usually defined as power from renewable energy that comes from wind, solar, biomass energy, etc. There are various definitions of clean resources. Some definitions include power produced from waste-to-energy and wood-fired plants that may still produce significant air emissions. Some states have defined certain local resources as clean that other states would not consider clean. For example, the state of Texas has defined power from efficient natural gas-fired power plants as clean. Some northwest states include power from large hydropower projects as clean although these projects damage fish populations. Various states have disclosure and labeling requirement for generation source and air emissions that assist customers in comparing electricity characteristics other than price. This allows customers to decide for themselves what they consider to be "clean." The federal government is also exploring this issue. Source: U.S. Department of Energy / Office of Energy Efficiency and Renewable Energy
Climate Change:
Climate change refers to any significant change in measures of climate (such as temperature, precipitation or wind) lasting for an extended period (decades or longer). Climate change may result from:
  • Natural factors, such as changes in the sun's intensity or slow changes in the Earth's orbit around the sun
  • Natural processes within the climate system (e.g., changes in ocean circulation)
Human activities that change the atmosphere's composition (e.g., through burning fossil fuels) and the land surface (e.g., deforestation, reforestation, urbanization and desertification) Source: Environmental Protection Agency
Compact Fluorescent Lamp (CFL):
Compact fluorescent lamps combine the energy efficiency of fluorescent lighting with the convenience and popularity of incandescent lamps. CFLs can replace incandescents that are roughly three-to-four times their wattage, saving up to 75 percent of the initial lighting energy. Although CFLs cost 3-10 times times more than comparable incandescent bulbs, they last 6-15 times as long (6,000-15,000 hours). Source: U.S. Department of Energy Office of Energy Efficiency and Renewable Energy
The preservation of resources through efficient and careful use. Source: U.S. Army Corps of Engineers
Corporate Average Fuel Economy (CAFE):
Corporate Average Fuel Economy (CAFE) is a way to measure the fuel economy of specific manufacturers' vehicles. It is expressed in miles per gallon (mpg) for a manufacturer's entire fleet of cars and light trucks. Source: National Housing, Transportation and Safety Administration
The use of direct, diffused or reflected sunlight to provide supplemental lighting for building interiors. Source: U.S. Department of Energy Office of Energy Efficiency and Renewable Energy
The amount of energy service or useful energy delivered per unit of energy input. Often used in reference to lighting systems, where the visible light output of a luminary is relative to power input; expressed in lumens per Watt; the higher the efficacy value, the higher the energy efficiency. Source: U.S. Department of Energy Office of Energy Efficiency and Renewable Energy
Under the First Law of Thermodynamics, efficiency is the ratio of work or energy output to work or energy input, and cannot exceed 100 percent. Efficiency under the Second Law of Thermodynamics is determined by the ratio of the theoretical minimum energy that is required to accomplish a task relative to the energy actually consumed to accomplish the task. Generally, the measured efficiency of a device, as defined by the First Law, will be higher than that defined by the Second Law. Source: U.S. Department of Energy Office of Energy Efficiency and Renewable Energy
Emissions Inventory:
A list of air pollutants emitted into a community's, state's, nation's, or the Earth's atmosphere in amounts per some unit time (e.g., day or year) by type of source. An emission inventory has both political and scientific applications. Source: Natsource
Energy Audit:
The process of determining energy consumption, by various techniques, of a building or facility. Source: U.S. Department of Energy Office of Energy Efficiency and Renewable Energy
Energy Performance Contracts:
Energy performance contracts are generally financing or operating leases provided by an Energy Service Company (ESCo) or equipment manufacturer for energy-saving installations. What distinguishes these contracts is that they provide a guarantee on energy savings from the installed retrofit measures, and they usually also offer a range of associated design, installation, and maintenance services. Source: U.S. Department of Energy Office of Energy Efficiency and Renewable Energy
Energy Performance Ratings:
You can use the energy performance ratings of windows, doors, and skylights to tell you their potential for gaining and losing heat, as well as transmitting sunlight into your home. Source: U.S. Department of Energy Office of Energy Efficiency and Renewable Energy
Energy Services Company:
A company that offers to reduce a client's utility costs, often with the cost savings being split with the client through an energy performance contract (EPC) or a shared-savings agreement Source: Think Energy
Energy Star:
Energy Star is a joint program of the U.S. Environmental Protection Agency (EPA) and the U.S. Department of Energy helping us all save money and protect the environment through energy efficient products and practices. In 1992 EPA introduced ENERGY STAR as a voluntary labeling program designed to identify and promote energy-efficient products to reduce greenhouse gas emissions. Source: Energy Star
Ethanol (CH3-CH2OH):
A clear, colorless, flammable oxygenated hydrocarbon. Ethanol is typically produced chemically from ethylene, or biologically from fermentation of various sugars from carbohydrates found in agricultural crops and cellulosic residues from crops or wood. It is used in the United States as a gasoline octane enhancer and oxygenate (blended up to 10 percent concentration). Ethanol can also be used in high concentrations (E85) in vehicles designed for its use. Source: Energy Information Administration
Global Warming:
Global warming is an increase in the average temperature of the atmosphere near the Earth's surface and in the troposphere, which can contribute to changes in global climate patterns. Global warming can occur from a variety of causes, both natural, and human-induced. In common usage, "global warming" often refers to the warming that can occur as a result of increased emissions of greenhouse gases from human activities. Source: U.S. Environmental Protection Agency
Greenhouse Gases (GHGs):
Gases in the Earth's atmosphere that produce the greenhouse effect. Changes in the concentration of certain greenhouse gases, due to human activity such as fossil fuel burning, increase the risk of global climate change. Greenhouse gases include water vapor, carbon dioxide, methane, nitrous oxide, halogenated fluorocarbons, ozone, perfluorinated carbons, and hydro fluorocarbons. Source: U.S. Environmental Protection Agency
High Performance Building:
A high-performance building is a building with energy, economic and environmental performance that is substantially better than standard practice. It is energy efficient, so it saves money and natural resources. It is a healthy place to live and work for its occupants and has relatively low impact on the environment. All this is achieved through a process called whole-building design. Source: U.S. Department of Energy Office of Energy Efficiency and Renewable Energy
Refers to vehicles that use two systems to propel the vehicle, using a rechargeable electric system as well as burning gasoline. Such vehicles typically have higher gas mileage and lower air emissions.
Incandescent Lamps:
Incandescent lamps operate without a ballast. They light up instantly, providing a warm light and excellent color rendition. You can also dim them. Light is emitted when electricity flows through-and heats-a tungsten filament. However, incandescent lamps have a low efficacy compared to other lighting options (10-17 lumens per Watt) and a short average operating life (750-2500 hours). Incandescent lamps are the least expensive to buy, but because of their relative inefficiency and short life spans, they usually are more expensive to operate. Source: U.S. Department of Energy Office of Energy Efficiency and Renewable Energy
Integrated Gasification-Combined Cycle Technology:
A clean-coal technology that combines coal gasification with combined cycle power generation. Coal, water and oxygen are fed to a gasifier, which produces syngas. This medium-Btu gas is cleaned (particulates and sulfur compounds removed) and is fed to a gas turbine. The hot exhaust of the gas turbine and heat recovered from the gasification process are routed through a heat-recovery generator to produce steam that drives a steam turbine to produce electricity. Source: U.S. Energy Information Administration
Intergovernmental Panel on Climate Change (IPCC):
The Intergovernmental Panel on Climate Change (IPCC) was established by the World Meteorological Organization (WMO) and the United Nations Environment Programme (UNEP) in 1988. Its main objective was to assess scientific, technical and socio-economic information relevant to the understanding of human-induced climate change, potential impacts of climate change and options for mitigation and adaptation. The IPCC has completed three assessment reports, developed methodology guidelines for national greenhouse gas inventories, special reports and technical papers. Source: Intergovernmental Panel on Climate Change
Leadership in Energy and Environmental Design (LEED):
LEED is the nationally accepted benchmark for the design, construction and operation of high performance green buildings. LEED gives building owners and operators the tools they need to have an immediate and measurable impact on their buildings' performances. LEED promotes a whole-building approach to sustainability by recognizing performance in five key areas of human and environmental health: sustainable site development, water savings, energy efficiency, materials selection and indoor environmental quality. Source: U.S. Green Building Council
Low Emitting and Fuel Efficient Vehicle:
Any vehicle that has either been classified as a Zero Emission Vehicle by the California Air Resources Board or has achieved a minimum green score of 40 on the American Council for an Energy Efficient Economy (ACEEE) annual vehicle rating guide.
Low Impact Development (LID):
One of LID's primary goals is to reduce runoff volume by infiltrating rainfall water to groundwater, evaporating rainwater back to the atmosphere after a storm and finding beneficial uses for water rather than exporting it as a waste product down storm sewers. The result is a landscape functionally equivalent to predevelopment hydrologic conditions, which means less surface runoff and less pollution damage to lakes, streams and coastal waters. Source: Natural Resource Defense Council
Rainwater Harvesting:
Rainwater harvesting is an ancient practice of catching and holding rain for later use. In a rainwater harvesting system, rain is gathered from a building rooftop or other source and is held in large containers for future use, such as watering gardens or washing cars. This practice reduces the demand on water resources and is excellent during times of drought. Source: Water Resources Group
Renewable Energy:
The term renewable energy generally refers to electricity supplied from renewable energy sources, such as wind and solar power, geothermal, hydropower and various forms of biomass. These energy sources are considered renewable sources because their fuel sources are continuously replenished. Under Virginia law, renewable energy refers to "energy derived from sunlight, wind, falling water, sustainable biomass, energy from waste, wave motion, tides, and geothermal power and does not include energy derived from coal, oil, natural gas or nuclear power." Source: U.S. Environmental Protection Agency
Renewable Portfolio Standard (Virginia):
This program calls for participating investor-owned utilities to reach a goal of 12 percent renewable energy by 2022, with intermediate goals of four percent in 2010 and seven percent in 2016. This is based on their energy sales in those years compared to total sales in 2007, excluding electricity from nuclear generation. Limitations are placed on the combustion of wood waste for compliance; however, wind power and solar energy count double toward the goals to encourage use of these preferred sources.
Smart Growth:
"Smart growth" covers a range of development and conservation strategies that help protect our natural environment and make our communities more attractive, economically stronger and more socially diverse. Based on the experience of communities around the nation that have used smart growth approaches to create and maintain great neighborhoods, the Smart Growth Network developed a set of 10 basic principles:
  1. Mix land uses
  2. Take advantage of compact building design
  3. Create a range of housing opportunities and choices
  4. Create walkable neighborhoods
  5. Foster distinctive, attractive communities with a strong sense of place
  6. Preserve open space, farmland, natural beauty and critical environmental areas
  7. Strengthen and direct development towards existing communities
  8. Provide a variety of transportation choices
  9. Make development decisions predictable, fair and cost-effective
  10. Encourage community and stakeholder collaboration in development decisions.
Source: U.S. Environmental Protection Agency
Sustainability is a new way of thinking about an age-old concern: ensuring that our children and grandchildren inherit a tomorrow that is at least as good as today, preferably better. Source: U.S. Environmental Protection Agency
Virginia Energy Plan:
Virginia legislation established an energy policy for the Commonwealth and directed the Department of Mines, Minerals and Energy (DMME), in consultation with the State Corporation Commission, Department of Environmental Quality and Virginia Center for Coal and Energy Research, to prepare a 10-year comprehensive Virginia Energy Plan (VEP) to implement the Commonwealth's energy policy. Source: Governor of Virginia
Green Tips
Evergreens are effective for blocking wind. Plant them in a staggered or double line to the northwest of your home.

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