Glossary Terms: All | A-D | E-I | J-Q | R-Z |

Joint Implementation (JI): One of the three market mechanisms established by the Kyoto Protocol. Joint Implementation occurs when an Annex B country invests in an emissions reduction or sink enhancement project in another Annex B country to earn emission reduction units (ERUs).

Kilowatt (kW): A unit of power, usually used for electric power or for energy consumption (use). A kilowatt equals 1,000 watts.

Kilowatt-hour (kWh): A unit of electrical energy. One kilowatt hour is the amount of energy consumed by 1000 watts of electrical power in one hour. A 100 watt bulb operated for 100 hours will consume 10 kilowatt hours of electricity. Kilowatt-hour is the most common billing unit for residential electricity consumption.

Kyoto Mechanisms: The Kyoto Protocol creates three market-based mechanisms that have the potential to help countries reduce the cost of meeting their emissions reduction targets. These mechanisms are Joint Implementation (Article 6), the Clean Development Mechanisms (Article 17).

Kyoto Protocol: An international agreement adopted in December 1997 in Kyoto, Japan. The Protocol sets binding emission targets for developed countries that would reduce their emissions on average 5.2 percent below 1990 levels.

Land Use, Land-Use Change and Forestry (LULUCF): Land uses and land-use changes can act either as sinks or as emission sources. It is estimated that approximately one-fifth of global emissions result from LULUCF activities. The Kyoto Protocol allows Parties to receive emissions credit for certain LULUCF activities that reduce net emissions.

Landfill Gas (LFG): The result of anaerobic bacteria that thrive in a landfills oxygen-free environment, resulting in the decomposition of the organic materials and the production of primarily carbon dioxide and methane.

Liquid Crystal Display (LCD): A display technology that uses liquid crystals to create images. LCD monitors are the most popular display technologies for desktop and laptop computers.

LEED-Leadership in Energy and Environmental Design: LEED-Leadership in Energy and Environmental Design: A rating system by the US Green Building Council (USGBC) that rates how “green” a building is in five categories: site design, energy-efficiency, resource-efficiency, water-efficiency, and health and indoor air quality. Previously only for commercial buildings, LEED is now expanding into homes (see below). (PATH)

LEED for Homes: A voluntary rating system of USGBC that promotes the design and construction of high-performance “green” homes. A green home uses less energy, water, and natural resources; creates less waste; and is healthier and more comfortable for the occupants. USGBC is now developing a LEED standard for existing homes. (USGBC)

Life Cycle Assessment (LCA): LCA is a technique to assess the environmental aspects and potential impacts associated with a product, process, or service, by: compiling an inventory of relevant energy and material inputs and environmental releases; evaluating the potential environmental impacts associated with identified inputs and releases; interpreting the results to help you make a more informed decision.

Life Cycle (Product): All stages of a product's development, from extraction of fuel for power to production, marketing, use, and disposal.

Liquefied Petroleum Gas (LPG): A group of hydrocarbon-based gases derived from crude oil refining or natural gas fractionation. They include ethane, ethylene, propane, propylene, normal butane, butylenes, isobutane, and isobutylene. For convenience of transportation, these gases are liquefied through pressurization.

Load: The power and energy requirements of users on the electric power system in a certain area or the amount of power delivered to a certain point.

Low-E Windows: Windows that are coated with a metallic glass (low emissivity) film to resist the flow of radiant heat. (EERE)

Low-Flow Faucet: A kitchen faucet meeting federal standards of 2.5 gallons per minute (gpm) maximum flow at 80 pounds per square inch water pressure or a bathroom faucet meeting the federals standard of 2-2.2 gallons per minute at 60 pounds per square inch of water pressure. Faucets with lower flow rates are available—2-2.2 gpm for kitchen faucets and as low as 0.5 gpm for bathroom faucets.

Low-Flow Showerhead: A showerhead meeting the federal standard of 2.5 gallons per minute (gpm) maximum flow at 80 pounds per square inch water pressure. Very high efficiency showerheads that operate at 1.5 gpm or less are currently available.

Manual J: The standard method for calculating residential cooling loads developed by the Air-Conditioning and Refrigeration Institute (ARI) and the Air-Conditioning Contractors of America (ACCA) based largely on the American Society of Heating, Refrigeration, and Air-Conditioning Engineer’s (ASHRAE) “Handbook of Fundamentals.” (WAPTAC)

Market Benefits: Benefits of a climate policy that can be measured in terms of avoided market impacts such as changes in resource productivity (e.g., lower agricultural yields, scarcer water resources) and damages to human-built environment (e.g., coastal flooding due to sea-level rise).

Mauna Loa Record: The record of measurement of atmospheric CO2 concentrations taken at Mauna Loa Observatory, Mauna Loa, Hawaii, since March 1958. This record shows the continuing increase in average annual atmospheric CO2 concentrations.

Megawatt (MW): A unit of electrical power equal to 1,000 kilowatts or 1,000,000 watts.

Methane (CH4): A colorless, nonpoisonous, flammable gas created by anaerobic decomposition of organic compounds. A major component of natural gas used in the home. CH4 is among the six greenhouse gases to be curbed under the Kyoto Protocol. Atmospheric CH4 is produced by natural processes, but there are also substantial emissions from human activities such as landfills, livestock and livestock wastes, natural gas and petroleum systems, coalmines, rice fields, and wastewater treatment. CH4 has a relatively short atmospheric lifetime of approximately 10 years, but its 100-year GWP is currently estimated to be approximately 23 times that of CO2.

Micro dams: A micro hydropower plant has a capacity of up to 100 kilowatts. A small or micro-hydroelectric power system can produce enough electricity for a home, farm, ranch, or village. Unlike large-scale hydro power, it does not attempt to interfere significantly with river flows.

Microwave Sounding Units (MSU): Sensors carried aboard Earth orbiting satellites that have been used since 1979 to monitor tropospheric temperatures.

Mitigation: Actions to reduce greenhouse gas emissions.

Montreal Protocol: (on Substances that Deplete the Ozone Layer) An international agreement that entered into force in January 1989 to phase out the use of ozone-depleting compounds such as methyl chloroform, carbon tetrachloride, and CFCs. CFCs are potent greenhouse gases which are not regulated by the Kyoto Protocol since they are covered by the Montreal Protocol.

Municipal Solid Waste (MSW): Common garbage or trash generated by industries, businesses, institutions, and homes.

National Action Plans: Plans submitted to the Conference of the Parties (COP) by all Parties outlining the steps that they have adopted to limit their anthropogenic GHG emissions. Countries must submit these plans as a condition of participating in the UN Framework Convention on Climate Change and, subsequently, must communicate their progress to the COP regularly.

Natural Gas: An odorless, colorless, tasteless, nontoxic, clean-burning fossil fuel. It is usually found in fossil fuel deposits and used as a fuel.

Negative Feedback: A process that results in a reduction in the response of a system to an external influence. For example, increased plant productivity in response to global warming would be a negative feedback on warming, because the additional growth would act as a sink CO2, reducing the atmospheric CO2 concentration.

Net Metering: For those consumers who have their own electricity-generating units, net metering allows for the flow of electricity both to and from the customer through a single, bi-directional meter. With net metering, during times when customer’s generation exceeds his or her use, electricity from the customer to the utility offsets electricity consumed at another time. (DSIRE)

Nitrogen Oxide (NOx): The result of photochemical reactions of nitric oxide in ambient air; major component of photochemical smog. Product of combustion from transportation and stationary sources and a major contributor to the formation of ozone in the troposphere and to acid deposition.

Nitrous Oxide (N2O): N2O is among the six greenhouse gases to be curbed under the Kyoto Protocol. N2O is produced by natural processes, but there are also substantial emissions from human activities such as agriculture and fossil fuel combustion. The atmospheric lifetime of N2O is approximately 100 years, and its 100-year GWP is currently estimated to be 296 times that of CO2.

Non-Market Benefits: Benefits of a climate policy that can be measured in terms of avoided non-market impacts such as human-health impacts (e.g., increased incidence of tropical diseases) and damages to ecosystems (e.g., loss of biodiversity).

Non-Party: A state that has not ratified the UNFCCC. Non-parties may attend talks as observers.

Nonrenewable Energy: Nonrenewable energy sources come out of the ground as liquids, gases and solids and cannot be replenished in a short period of time. Nonrenewable sources of energy can be categorized into fossil fuels (e.g. oil, natural gas, and coal) and nuclear (e.g. uranium). We get most of our supplied energy from nonrenewable sources. (EIA)

Off-Grid Home: A home (or building) that is not connected to the power grid or to municipal sewer or water lines. They must produce their own energy and find and dispose of their own water. (PATH)

Off-Peak/On-Peak: Blocks of time when energy demand and price is low (off-peak) or high (on-peak)

Passive Solar (Building) Design: A building design that uses structural elements of a building to heat and cool a building without the use of mechanical equipment. It requires careful consideration of the local climate and solar energy resource, building orientation, and landscape features. Heat is distributed primarily by natural convection and radiation, though fans can also be used to circulate room air or ensure proper ventilation. (EERE)

Particulate Matter: Also known as particle pollution or PM, is a complex mixture of extremely small particles and liquid droplets.

Peak Load Reduction: Reducing electric load during the times when electric demand is high, such as on a hot summer day. Load reduction can be accomplished by temporary demand response, load shifting, or through permanent demand reduction from energy-efficiency. (NYSERDA)

Perfluorocarbons (PFCs): PFCs are among the six types of greenhouse gases to be curbed under the Kyoto Protocol. PFCs are synthetic industrial gases generated as a by-product of aluminum smelting and uranium enrichment. They also are used as substitutes for CFCs in the manufacture of semiconductors. There are no natural sources of PFCs. PFCs have atmospheric lifetimes of thousands to tens of thousands of years and 100-year GWPs thousands of times that of CO2, depending on the gas.

Personal Income Tax Incentives: An incentive to encourage purchase of renewable energy or energy-efficient equipment. Some states offer personal income tax credits up to a certain percentage or predetermined dollar amount for the cost or installation or renewable energy equipment. (DSIRE)

Phantom Load: Any appliance that consumes power even when it is turned off. Examples of phantom loads include equipment chargers, appliances with electronic clocks or timers, appliances with remote controls, and appliance with wall cubes (a small box that plugs into an AC outlet to power appliance). Phantom loads can be a significant part (6%) of a household’s electric use. (EERE)

Polluter Pays Principle (PPP): The principle that countries should in some way compensate others for the effects of pollution that they (or their citizens) generate or have generated.

Positive Feedback: A process that results in an amplification of the response of a system to an external influence. For example, increased atmospheric water vapor in response to global warming would be a positive feedback on warming, because water vapor is a GHG.

ppm or ppb: Abbreviations for “parts per million” and “parts per billion,” respectively - the units in which concentrations of greenhouse gases are commonly presented. For example, since the pre-industrial era, atmospheric concentrations of carbon dioxide have increased from 270 ppm to 370 ppm.

Programmable Thermostat: A thermostat for space heating and cooling that allows the temperature to be set automatically to a value that results in less heating or cooling in periods when they are not needed.

Quantified Emission Limitation and Reduction QELRC: Also known as QELRO (Quantified Emission Limitation and Reduction Objective): The quantified commitments for GHG emissions listed in Annex B of the Kyoto Protocol. QELRCs are specified in percentages relative to 1990 emissions.