Glossary

Almost everyone today uses electricity in one form or another. Most of us take for granted the process that starts with the creation of electricity at a power plant or hydro electric facility and ends with the residential, commercial or industrial user powering their microwave oven or computer monitor.

Listed below is a compilation of words and terms related to electricity and energy conservation. As space does not allow for the inclusion of every word or term in the English language that may be applicable to these topics, the information listed below is intended to further oneęs understanding and foster more inquiry into the use and conservation of electricity.

If you feel that there are some additional words or terms that should have been included, please let us know. While we cannot guarantee that all submissions will be included, we welcome the feedback and additional information.

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alternating current (ac): Flow of electricity that constantly changes direction between positive and negative sides. Almost all power produced by electric utilities in the United States moves in current that shifts direction at a rate of 60 times per second. http://www.school-for-champions.com/science/ac.htm
amp hour: Quantity of electricity or measure of charge. How many amps flow or can be provided over a one hour period. Most batteries are rated in amp hours ("AH").
ampere: Basic unit of electric current, symbol A or amp, named for the 19th-century French physicist Andre Marie Ampere (1775-1836).
Atomic Energy Commission: The independent civilian agency of the federal government with statutory responsibility to supervise and promote use of nuclear energy. Functions were taken over in 1974 by the Energy Research and Development Administration (now part of the U.S. Department of Energy) and the Nuclear Regulatory Commission. http://www.nrc.gov/who-we-are/history.html
AWG: American Wire Gauge, a standard system for designating the size of electrical wire. The higher the number, the smaller the wire. Most house wiring is #12 or 14. In most other countries, wire is specified by the size in millimeters.
blackouts: A planned or unplanned cessation of electrical power that could be caused by a natural disaster or overuse of the electrical grid when demand for power outstrips the supply available.
breeder: A nuclear reactor that produces more fuel than it consumes. The breeder, invented in the United States, is used as a power source in several European countries.
brownouts: A controlled power reduction in which the utility decreases the voltage on the power lines, so customers receive weaker electric current. Brownouts can be used if total power demand exceeds the maximum available supply. The typical household does not notice the difference. From November 2000 through May 2001, California experienced a series of planned brownouts to groups of customers, for a limited duration, in order to reduce total system load and avoid a blackout due to alleged electrical shortages.
caulking: Material used to make an air-tight seal by filling in cracks, such as those around windows and doors.
circuit: One complete run of a set of electric conductors from a power source to various electrical devices (appliances, lights, etc.) and back to the same power source.
conservation: Steps taken to cause less energy to be used than would otherwise be the case. These steps may involve improved efficiency, avoidance of waste, reduced consumption, etc. They may involve installing equipment (such as a computer to ensure efficient energy use), modifying equipment (such as making a boiler more efficient), adding insulation, changing behavior patterns, etc.
CSA International: Abbreviation for Canadian Standards Association International ("CSA"), a provider of product testing and certification services. CSA tests products for compliance to national and international standards, and issues certification marks for qualified products. Certification marks tell potential customers and users that a product has been evaluated by a formal process-involving examination, testing and follow-up inspection-and that it complies with applicable standards for safety and performance.
daylighting: The use of sunlight to supplement or replace electric lighting
demand: The level at which electricity or natural gas is delivered to users at a given point in time. Electric demand is expressed in kilowatts.
(U.S.) DEPARTMENT OF ENERGY (US DOE): The federal department established by the Department of Energy Organization Act to consolidate the major federal energy functions into one cabinet-level department that would formulate a comprehensive, balanced national energy policy. DOE's main headquarters are in Washington, D.C. www.doe.gov
Direct current (dc): Electrical current that flows in one direction only. Automobiles and many battery-powered devices use direct current.
distribution system: The substations, transformers and lines that convey electricity from high-power transmission lines to ultimate consumers. For more informaiton see "grid".
double glazing: Windows having two sheets of glass with an airspace between.
Edison, Thomas Alva: One of the greatest American inventors of all time. Edison began to work at an early age and continued to work right up until his death. Edison developed the incandescent lamp, or light bulb in 1879. Edison was not the first person to produce a light bulb, but his design proved popular because it gave off a moderate amount of light and lasted a long time. During his career Edison patented more than 1,000 inventions, including the electric light, the phonograph, and the motion-picture camera. These three inventions gave rise to giant industriesăelectric utilities, phonograph and record companies, and the film industryăthus changing the work and leisure habits of people throughout the world. www.thomasedison.com/
EEI (Edison Electric Institute).: An association of electric companies formed in 1933 "to exchange information on industry developments and to act as an advocate for utilities on subjects of national interest."
ELCON (Electricity Consumers Resources Council): ELCON is an association of 28 large industrial consumers of electricity. ELCON members account for over five percent of all electricity consumed in the United States. ELCON was formed in 1976 "to enable member companies to work cooperatively for the development of coordinated, rational and consistent policies affecting electric energy supply and pricing at the federal, state, and local levels."
electricity: One of the basic forms of energy. Electricity is associated with electric charge, a property of certain elementary particles such as electrons and protons, two of the basic particles that make up the atoms of all ordinary matter. Electric charges can be stationary, as in static electricity, or moving, as in an electric current.
energy conservation: In addition to developing alternative sources of energy, energy supplies can be extended by the conservation (the planned management) of currently available resources. Three types of possible energy conservation practices may be described. The first type is curtailment, that is, doing withoutăfor example, closing factories to reduce the amount of power consumed or cutting back on travel to reduce the amount of gasoline burned. The second type is overhaul, that is, changing the way people live and the way goods and services are producedăfor example, slowing further suburbanization of society, using less energy-intensive materials in production processes, and decreasing the amount of energy consumed by certain products (such as automobiles). The third type involves the more efficient use of energy, that is, adjusting to higher energy costsăfor example, investing in cars that go farther per unit of fuel, capturing waste heat in factories and reusing it, and insulating houses. This third option requires less drastic changes in lifestyle, so governments and societies most commonly adopt it over the other two options.
Energy Star: A program sponsored by the United States Department of Energy. ENERGY STAR is a government-backed program helping businesses and individuals protect the environment through superior energy efficiency. www.energystar.gov
electric current: A flow of electrons; electricity, amps.
efficiency: The ratio of the useful energy delivered by a dynamic system (such as a machine, engine, or motor) to the energy supplied to it over the same period or cycle of operation. The ratio is usually determined under specific test conditions.
electric generator: A device that converts a heat, chemical or mechanical energy into electricity.
electric resistance heater: A device that produces heat through electric resistance. For example, an electric current is run through a wire coil with a relatively high electric resistance, thereby converting the electric energy into heat which can be transferred to the space by fans.
electirc radiant heating: A heating system in which electric resistance is used to produce heat which radiates to nearby surfaces. There is no fan component to a radiant heating system.
FERC: Abbreviation for Federal Energy Regulatory Commission. An independent regulatory commission within the U.S. Department of Energy that has jurisdiction over energy producers that sell or transport fuels for resale in interstate commerce; the authority to set oil and gas pipeline transportation rates and to set the value of oil and gas pipelines for ratemaking purposes; and regulates wholesale electric rates and hydroelectric plant licenses. www.ferc.gov/
Franklin, Benjamin
: One of the United Statesę greatest scientist and inventors, Franklin (1706-1790) is responsible and best known for his experiments with electricity and the famous –kite and key experiment” but that was only one of the many investigations and scientific topics he studied. Franklin can also be credited with inventing a smokeless fireplace, bifocal glasses, and the lightening rod. He was also the first postmaster of the United States and had much influence in setting up the first police station system, library, and volunteer fire department. http://www.ushistory.org/franklin/
fan coil: A component of a heating, ventilation and air conditioning (HVAC) system containing a fan and heating or cooling coil, used to distribute heated or cooled air.
geothermal: Relating to the internal heat of the earth. In energy language, the term is used most frequently to describe the energy systems that revolve around using steam generated from inside the earth to generate electricity, also referred to geothermal power. http://www.geothermal.org/what.html
gigawatt: One thousand megawatts (1,000 MW) or, one million kilowatts (1,000,000 kW) or one billion watts (1,000,000,000 watts) of electricity. One gigawatt is enough to supply the electric demand of about one million average California homes.
gigawatt hour (GWH): One million kilowatt-hours of electric power. California's electric utilities generated a total of about 270,000 gigawatt-hours.
grid: Informal name given to the system of supplying electrical power from the source of generation to the end user, for example from the hydro-electric dam (source) to the residential home (end user).
hertz: In this case, not the car rental company. A unit of frequency measurement defined as one cycle for one second. Abbreviated –hz”. Used to describe computers systems and electrical current systems. Named after Heinrich Rudolf Hertz (1857-1894), a German physicist who was the first to produce radio waves artificially. www.ideafinder.com/history/inventors/hertz.htm
horsepower (HP): A unit for measuring the rate of doing work. One horsepower equals about three-fourths of a kilowatt (745.7 watts).
HVAC (Heating Ventilation and Air Conditioning): A system that provides heating, ventilation and/or cooling within or associated with a building.
hydroelectric power: Electricity produced by falling water that turns a turbine generator. Also referred to as HYDRO. http://www.nrel.gov/learning/
hydropower: See hydro-electric power
hz: Abbreviation for hertz. www.ideafinder.com/history/inventors/hertz.htm
incandescent lamp: An electric lamp in which a filament is heated by an electric current until it emits visible light.
Independent System Operatror (ISO): A neutral operator responsible for maintaining instaneous balance of the grid system. The ISO performs its function by controlling the dispatch of flexible plants to ensure that loads match resources available to the system.
kinetic energy: The energy possessed by a body because of its motion, equal to one half the mass of the body times the square of its speed.
kilovolt (kv): One-thousand volts (1,000). Distribution lines in residential areas usually are 12 kv (12,000 volts).
kilowatt (kW): One thousand (1,000) watts. A unit of measure of the amount of electricity needed to operate given equipment. On a hot summer afternoon a typical home, with central air conditioning and other equipment in use, might have a demand of four kW each hour.
kilowatt hour(kWh): The most commonly-used unit of measure telling the amount of electricity consumed over time. It means one kilowatt of electricity supplied for one hour. In 1989, a typical California household consumes 534 kWh in an average month.
lifeline rates: Rates charged by a utility company for the low income, the disadvantaged and senior citizens. The rates provide a discount for minimum necessary utilities, such as electricity requirements of typically 300 to 400 kilowatt/hours per month.
load: The amount of electric power supplied to meet one or more end user's needs. Also anything in an electrical circuit that, when the circuit is turned on, draws power from that circuit.
mega-volt: one million volts
mega-watt (MW): One thousand kilowatts (1,000 kW) or one million (1,000,000) watts. One megawatt is enough energy to power 1,000 average California homes.
megawatt hour(MWh): One thousand kilowatt-hours, or an amount of electricity that would supply the monthly power needs of a typical home having an electric hot water system.
meter: A device for measuring levels and volumes of a customer's gas or electricity use.
municple utility: A provider of utility services owned and operated by a municipal government.
nuclear energy: Power obtained by splitting heavy atoms (fission) or joining light atoms (fusion). A nuclear energy plant uses a controlled atomic chain reaction to produce heat. The heat is used to make steam run conventional turbine generators.
Nuclear Regulatory Commission (NRC): An independent federal agency that ensures that strict standards of public health and safety, environmental quality and national security are adhered to by individuals and organizations possessing and using radioactive materials. The NRC is the agency that is mandated with licensing and regulating nuclear power plants in the United States. It was formally established in 1975 after its predecessor, the Atomic Energy Commission, was abolished.
ohm: The unit of measure for electrical resistance. A resistance of 1 ohm will pass 1 ampere of current when a voltage of 1 volt is applied. Named after Georg Simon Ohm (1789-1854), a German physicist noted for his contributions to mathematics, acoustics, and the measurement of electrical resistance.
outage: An interruption of electric service that is temporary (minutes or hours) and affects a relatively small area (buildings or city blocks). For more information see "blackout".
passive solar energy: Use of the sun to help meet a building's energy needs by means of architectural design (such as arrangement of windows) and materials (such as floors that store heat, or other thermal mass).
passive solar system: A solar heating or cooling system that uses no external mechanical power to move the collected solar heat.
peak load; peak demand: The maximum load, or usage, of electrical power occurring in a given period of time, typically a day.
photovoltaic: The system of producing energy when exposed to radiant energy, especially light.
photovoltaic Cell: Also known as solar cell, a semiconductor device that converts the energy of sunlight into electric energy.
PV: Abbreviation for photovoltaic(s).
resistance: All components in electrical circuits exhibit one or more of the characteristics of resistance, capacitance, and inductance. The commonly used unit of resistance is the ohm, which is the resistance of a conductor in which a potential difference of 1 volt causes a current flow of 1 ampere.
rolling blackouts: A planned systematic shut off of electrical power by the utility provider caused when demand outstrips supply, for example on hot summer days when electrical demand caused by air conditioning usage exceeds available supply.
R-Value: A unit of thermal resistance used for comparing insulating values of different material. It is basically a measure of the effectiveness of insulation in stopping heat flow. The higher the R-value number, a material, the greater its insulating properties and the slower the heat flow through it. The specific value needed to insulate a home depends on climate, type of heating system and other factors.
renewable energy: Resources that constantly renew themselves or that are regarded as practically inexhaustible. These include solar, wind, geothermal, hydro and wood. Although particular geothermal formations can be depleted, the natural heat in the earth is a virtually inexhaustible reserve of potential energy. Renewable resources also include some experimental or less-developed sources such as tidal power, sea currents and ocean thermal gradients.
renewable resources: Renewable energy resources are naturally replenishable, but flow-limited. They are virtually inexhaustible in duration but limited in the amount of energy that is available per unit of time. Some (such as geothermal and biomass) may be stock-limited in that stocks are depleted by use, but on a time scale of decades, or perhaps centuries, they can probably be replenished. Renewable energy resources include: biomass, hydro, geothermal, solar and wind. In the future they could also include the use of ocean thermal, wave, and tidal action technologies. Utility renewable resource applications include bulk electricity generation, on-site electricity generation, distributed electricity generation, non-grid-connected generation, and demand-reduction (energy efficiency) technologies.
reserve: The extra generating capability that an electric utility needs, above and beyond the highest demand level it is required to supply to meet its users needs.
SEER (Seasonal Energy Efficiency Ratio): The total cooling output of a central air conditioning unit in Btus during its normal usage period for cooling divided by the total electrical energy input in watt-hours during the same period, as determined using specified Federal test procedures.
shade screen: A screen affixed to the exterior of a window or other glazed opening, designed to reduce the solar radiation reaching the glazing.
setback thermostat: A device, containing a clock mechanism, which can automatically change the inside temperature maintained by the HVAC system according to a preset schedule. The heating or cooling requirements can be reduced when a building is unoccupied or when occupants are asleep.
solar energy: Energy from the sun. The heat that builds up in your car when it is parked in the sun is an example of solar energy.
solar collector: A component of an active or passive solar system that absorbs solar radiation to heat a transfer medium which, in turn, supplies heat energy to the space or water heating system.
solar cell: A photovoltaic cell that can convert light directly into electricity. A typical solar cell uses semiconductors made from silicon.
thermostat: An automatic control device designed to be responsive to temperature and typically used to maintain set temperatures by cycling the HVAC system.
therm: One hundred thousand (100,000) British thermal units (1 therm = 100,000 Btu).
Time of Use (TOU) Rates: The pricing of electricity based on the estimated cost of electricity during a particular time block. Time-of-use rates are usually divided into three or four time blocks per twenty-four hour period (on-peak, mid-peak, off-peak and sometimes super off-peak) and by seasons of the year (summer and winter). Real-time pricing differs from TOU rates in that it is based on actual (as opposed to forecasted) prices which may fluctuate many times a day and are weather-sensitive, rather than varying with a fixed schedule.
Time of Use Meter: A measuring device that records the times during which a customer uses various amounts of electricity. This type of meter is used for customers who pay time-of-use rates.
UL: Abbreviation for Underwriters Laboratory., Underwriters Laboratories Inc. (UL) is an independent, not-for-profit product-safety testing and certification organization. UL has tested products for public safety for more than a century. Founded in 1894, UL is the recognized reputation as a leader in product-safety testing and certification within the United States. Today, UL services extend to helping companies achieve global acceptance, whether for an electrical device, a programmable system, or an organization's quality process. http://www.ul.com/
VAC: Volts ac (alternating current)
VDC: Volts dc (direct current)
Vmp: Voltage at maximum power
Voc: Open-circuit voltage
volt: A unit of electromotive force. It is the amount of force required to drive a steady current of one ampere through a resistance of one ohm. Electrical systems of most homes and office have 120 volts.
voltaic: The production of electricity by chemical action.
watt: A unit of measure of electric power at a point in time, as capacity or demand. One watt of power maintained over time is equal to one joule per second. Some Christmas tree lights use one watt. The watt is named after Scottish inventor James Watt and is capitalized when shortened to w and used with other abbreviations, as in kWh (kilowatt hour).
wattage: An amount of power, mainly electric power, expressed in watts or kilowatts and also the measure of electric power required by an appliance or a device.
wind energy: Electrical energy generated by wind driven turbines such as windmills.
watt-meter: An instrument for measuring in watts the power flowing in a circuit.
Watt-Minder: A low cost Appliance and Cost Meter used to measure the costs of operation 120 volt-60 hz household appliances.
Westinghouse, George: American engineer (1846-1914) and manufacturer who received more than 400 patents for his many inventions, including a practical method for transmitting electric power. He founded the Westinghouse Electric Company in 1886.
weatherstripping: Specially designed strips, seals and gaskets installed around doors and windows to limit air leakage.
watt-hour: One watt of power expended for one hour. One thousandth of a kilowatt-hour.

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