This is a glossary of energy terms. It is based on the glossary published by the California Energy Commission. We hope you will find it helpful as a reference.
ACCESS CHARGE -- A charge paid by all market participants withdrawing energy from the ISO controlled grid. The access charge will recover the portion of a utility's transmission revenue requirement not recovered through the variable usage charge.
ACTIVE SOLAR ENERGY -- Solar radiation used by special equipment to provide space heating, hot water or electricity.
ACTIVE SOLAR ENERGY SYSTEM -- A system designed to convert solar radiation into usable energy for space, water heating, or other uses. It requires a mechanical device, usually a pump or fan, to collect the sun's energy.
ACOP (Adjusted Coefficient of Performance) -- A standard rating term that was used to rate the efficiency of heat pumps in California. ACOP was replaced by Heating Seasonal Performance Factor (HSPF) in 1988.
ADDITION -- An alteration to an existing building that increases conditioned space.
ADJUSTMENT BID -- A bid that is used by the ISO to adjust supply or demand when congestion is anticipated.
ADVERSE HYDRO -- Water conditions limiting the production of hydroelectric power. In years having below-normal levels of rain and snow, and in seasons having less-than-usual runoff from mountain snowpack, there is then less water available for hydro energy production.
AFTER-MARKET -- broad term that applies to any change after the original purchase, such as adding equipment not a part of the original purchase. As applied to alternative fuel vehicles, it refers to conversion devices or kits for conventional fuel vehicles.
AGGREGATOR -- An entity responsible for planning, scheduling, accounting, billing, and settlement for energy deliveries from the aggregator's portfolio of sellers and/or buyers. Aggregators seek to bring together customers or generators so they can buy or sell power in bulk, making a profit on the transaction.
AIR CHANGE -- The replacement of a quantity of air in a space within a given period of time, typically expressed as air changes per hour. If a building has one air change per hour, this is equivalent to all of the air in the building being replaced in a one-hour period.
AIR CONDITIONER -- An assembly of equipment for air treatment consisting of a means for ventilation, air circulation, air cleaning, and heat transfer (either heating or cooling). The unit usually consists of an evaporator or cooling coil, and an electrically-driven compressor and condenser combination.
AIR FILM -- A layer of still air adjacent to a surface which provides some thermal resistance.
AIR FILM COEFFICIENT -- A measure of the heat transfer through an air film. [See ASHRAE Table 1, ASHRAE Handbook, 1985 Fundamentals]
AIR-TO-AIR HEAT EXCHANGER -- A device with separate air chambers that transfers heat between the conditioned air being exhausted and the outside air being supplied to a building.
AIR POLLUTION -- Unwanted particles, mist or gases put into the atmosphere as a result of motor vehicle exhaust, the operation of industrial facilities or other human activity./
ALTERATION -- Any change or modification to a building's construction. [See Addition].
AMBIENT AIR TEMPERATURE -- Surrounding temperature, such as the outdoor air temperature around a building.
ALCOHOL FUELS -- A class of liquid chemicals that have certain combinations of hydrogen, carbon and oxygen, and that are capable of being used as fuel.
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.
ALTERNATIVE ENERGY SOURCES -- See RENEWABLE ENERGY.
ALTERNATIVE (transportation) FUELS -- as defined by the National Energy Policy Act (EPAct) the fuels are: methanol, denatured ethanol and other alcohols, separately or in mixtures of 85 percent by volume or more (or other percentage not less than 70 percent as determined by U.S. Department of Energy rule) with gasoline or other fuels; CNG; LNG; LPG; hydrogen; "coal-derived liquid fuels;" fuels "other than alcohols" derived from "biological materials;" electricity, or any other fuel determined to be "substantially not petroleum" and yielding "substantial energy security benefits and substantial environmental benefits."
ALTERNATIVE FUEL VEHICLE (AFV) -- motor vehicles that run on fuels other than petroleum-based fuels. As defined by the National Energy Policy Act (EPAct), this excludes reformulated gasoline as an alternative fuel.
AMBIENT -- The surrounding atmosphere; encompassing on all sides; the environment surrounding a body but undisturbed or unaffected by it.
ANSI -- American National Standards Institute is the national organization that coordinates development and maintenance of consensus standards and sets rules for fairness in their development. ANSI also represents the USA in developing international standards.
ANCILLARY SERVICES -- The services other than scheduled energy that are required to maintain system reliability and meet WSCC/NERC operating criteria. Such services include spinning, non-spinning, and replacement reserves, voltage control, and black start capability.
AMPERE (Amp) -- The unit of measure that tells how much electricity flows through a conductor. It is like using cubic feet per second to measure the flow of water. For example, a 1,200 watt, 120-volt hair dryer pulls 10 amperes of electric current (watts divided by volts).
ANCILLARY SERVICES -- Services that the Independent System Operator may develop, in cooperation with market participants, to ensure reliability and to support the transmission of energy from generation sites to customer loads. Such services may include: regulation, spinning reserve, non-spinning reserve, replacement reserve, voltage support, and black start.
ANGLE OF INCIDENCE -- The angle that the sun's rays make with a line perpendicular to a surface. The angle of incidence determines the percentage of direct sunshine intercepted by a surface.
ANNUAL MAXIMUM DEMAND -- The greatest of all demands of the electrical load which occurred during a prescribed interval in a calendar year.
ANIMAL WASTE CONVERSION -- Process of obtaining energy from animal wastes. This is a type of biomass energy.
AFUE (Annual Fuel Utilization Efficiency) -- A measure of heating efficiency, in consistent units, determined by applying the federal test method for furnaces. This value is intended to represent the ratio of heat transferred to the conditioned space by the fuel energy supplied over one year. [See California Code of Regulations, Title 20, Section 1602(d)(1)]
ANTHRACITE -- Hard coal, found deep in the earth. It burns very hot, with little flame. It usually has a heating value of 12,000-15,000 British thermal units (Btus) per pound.
APPLIANCE EFFICIENCY STANDARDS -- California Code of Regulations, Title 20, Chapter 2, Subchapter 4: Energy Conservation, Article 4: Appliance Efficiency Standards. Appliance Efficiency Standards regulate the minimum performance requirements for appliances sold in California and apply to refrigerators, freezers, room air conditioners, central air conditioners, gas space heaters, water heaters, plumbing fittings, fluorescent lamp ballasts and luminaires, and ignition devices for gas cooking appliances and gas pool heaters. New National Appliance Standards are in place for some of these appliances and will become effective for others at a future date.
APPLIANCE SATURATION -- A percentage telling what proportion of all households in a given geographical area have a certain appliance.
APPLICANT -- Applicant means any person who submits an application for certification pursuant to the provisions of this division, including, but not limited to, any person who explores for or develops geothermal resources.
APPLICATION -- Application means any request for certification of any site and related facility filed in accordance with the procedures established pursuant to this division. An applicant for a geothermal powerplant and related facilities may propose more than one site and related geothermal facilities in the same application.
AREA LOAD -- The total amount of electricity being used at a given point in time by all consumers in a utility's service territory.
ASHRAE -- Acronym for American Society of Heating, Refrigerating and Air- Conditioning Engineers.
ASH -- Non-organic, non-flammable substance left over after combustible material has been completely burned.
ASSOCIATED GAS -- Natural gas that can be developed for commercial use, and which is found in contact with oil in naturally occurring underground formations.
ATGAS -- Synthetic gas produced by dissolving coal in a bath of molten iron. The process was developed by Applied Technology, Inc. Synthetic gas may be used as a substitute for natural gas in industrial and home uses.
ATOM --The smallest unit of an element consisting of a dense positively charged nucleus (of protons and neutrons) orbited by negatively charged electrons.
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.
ATOMIC NUCLEUS -- The positively charged core of an atom.
AUXILIARY ENERGY SUBSYSTEM -- Equipment using conventional fuel to supplement the energy output of a solar system. This might be, for example, an oil- fueled generator that adds to the electrical output of a substitutes for the solar system during long overcast periods when there is not enough sunlight.
AUXILIARY EQUIPMENT -- Extra machinery needed to support the operation of a power plant or other large facility.
AVERAGE COST -- The revenue requirement of a utility divided by the utility's sales. Average cost typically includes the costs of existing power plants, transmission, and distribution lines, and other facilities used by a utility to serve its customers. It also included operating and maintenance, tax, and fuel expenses.
AVERAGE DEMAND -- The energy demand in a given geographical area over a period of time. For example, the number of kilowatt-hours used in a 24-hour period, divided by 24, tells the average demand for that period.
AVERAGE HYDRO -- Rain, snow and runoff conditions that provide water for hydroelectric generation equal to the most commonly occurring levels. Average hydro usually is a mean indicating the levels experienced most often in a 104-year period.
AVOIDED COST -- (Regulatory) The amount of money that an electric utility would need to spend for the next increment of electric generation to produce or purchase elsewhere the power that it instead buys from a cogenerator or small-power producer. Federal law establishes broad guidelines for determining how much a qualifying facility (QF) gets paid for power sold to the utility.
AVOIDED COST -- The cost the utility would incur but for the existence of an independent generator or other energy service option. Avoided cost rates have been used as the power purchase price utilities offer independent suppliers (see Qualifying Facilities).
AZIMUTH--The angular distance between true south and the point on the horizon directly below the sun. Typically used as an input for opaque surfaces and windows in computer programs for calculating the energy performance of buildings.
BALLAST - A device that provides starting voltage and limits the current during normal operation in electrical discharge lamps (such as fluorescent lamps).
BARREL - In the petroleum industry, a barrel is 42 U.S. gallons. One barrel of oil has an energy content of 6 million British thermal units. It takes one barrel of oil to make enough gasoline to drive an average car from Los Angeles to San Francisco and back (at 18 miles per gallon over the 700-mile round trip).
BARRELS PER DAY EQUIVALENT (BPD-Equivalent) - A unit of measure that tells how much oil would have to be burned to produce the same amount of energy. For example, California's hydroelectric generation in 1983 was 58,000 barrels per day equivalent.
BASE LOAD - The lowest level of power production needs during a season or year.
BASE LOAD UNIT - A power generating facility that is intended to run constantly at near capacity levels, as much of the time as possible.
BASELINE FORECAST - A prediction of future energy needs which does not take into account the likely effects of new conservation programs that have not yet been started.
BASE RATE - That portion of the total electric or gas rate covering the general costs of doing business unrelated to fuel expenses.
BATTERY - A device that stores energy and produces electric current by chemical action.
BENZENE - A type of colorless liquid hydrocarbon that can be used as a motor fuel. Its chemical symbol is C6H6.
BGP - The acronym for Burbank, Glendale and Pasadena, three electric, municipal utilities serving those southern California cities. The three are usually grouped statistically, though they are separate entitites.
BIENNIAL REPORT - The report formerly issued by the California Energy Commission to the Governor and the Legislature every odd-numbered year assessing California's energy industry. (See also Commission reports page.) The Biennial Report is supported by four policy documents that are issued every even-numbered year: the Electricity Report, the Fuels Report, the Conservation (or Efficiency) Report and the Energy Development Report. The Biennial Report was replaced by the Integrated Energy Policy Report.
BI-FUEL VEHICLE - A vehicle with two separate fuel systems designed to run on either fuel, using only one fuel at a time. These systems are advantageous for drivers who do not always have access to an alternative fuel refueling station. Bi-fuel systems are usually used in light-duty vehicles. One of the two fuels is typically an alternative fuel.
BI-GAS - A process being developed as a means of making synthetic gas from coal. The synthetic gas would be intended to substitute for natural gas in meeting industrial and home energy needs.
BILATERAL CONTRACT - A two-party agreement for the purchase and the sale of energy products and services.
BIOCONVERSION - Processes that use plants or micro-organisms to change one form of energy into another. For example, an experimental process uses algae to convert solar energy into gas that could be used for fuel.
BIODIESEL - a biodegradable transportation fuel for use in diesel engines that is produced through the transesterfication of organically- derived oils or fats. It may be used either as a replacement for or as a component of diesel fuel.
BIOMASS - Energy resources derived from organic matter. These include wood, agricultural waste and other living-cell material that can be burned to produce heat energy. They also include algae, sewage and other organic substances that may be used to make energy through chemical processes.
BIOSPHERE - The zone at and adjacent to the earth's surface where all life exists; all living organisms of the earth.
BITUMINOUS COAL - Soft coal containing large amounts of carbon. It has a luminous flame and produces a great deal of smoke.
BLACKOUT - A power loss affecting many electricity consumers over a large geographical area for a significant period of time.
BOILER - A closed vessel in which water is converted to pressurized steam.
BOILING WATER REACTOR - (BWR) A nuclear power unit in which water used as a coolant is allowed to boil at the core. The resulting steam may be used to drive electric turbines.
BOTTLED GAS - The liquified petroleum gases propane and butane, contained under moderate pressure (about 125 pounds per square inch and 30 pounds per square inch respectively), in cylinders.
BOTTOMING CYCLE - A means to increase the thermal efficiency of a steam electric generating system by converting some waste heat from the condenser into electricity rather than discharging all of it into the environment.
BPA - (short for Bonneville Power Administration) - One of five federal power marketing administrations that sell low-cost electric power produced by federal hydro electric dams to agricultural and municipal users. BPA serves Idaho, Oregon, and Washington as well as parts of Nevada and Wyoming. It also sells power to California companies in "wheeling" trades.
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.
BRITISH THERMAL UNIT (Btu) - The standard measure of heat energy. It takes one Btu to raise the temperature of one pound of water by one degree Fahrenheit at sea level. For example, it takes about 2,000 Btu to make a pot of coffee. One Btu is equivalent to 252 calories, 778 foot-pounds, 1055 joules, and 0.293 watt-hours. Note: In the abbreviation, only the B is capitalized.
BROKER - A retail agent who buys and sells power. The agent may also aggregate customers and arrange for transmission, firming and other ancillary services as needed.
BROWNOUT - 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.
BUILDING ENERGY EFFICIENCY STANDARDS - California Code of Regulations (California Code of Regulations), Title 24, Part 2, Chapter 2-53; regulating the energy efficiency of buildings constructed in California.
BUILDING ENVELOPE - The assembly of exterior partitions of a building which enclose conditioned spaces, through which thermal energy may be transferred to or from the exterior, unconditioned spaces, or the ground. [See California Code of Regulations, Title 24, Section 2-5302]
BULK POWER SUPPLY - Often this term is used interchangeably with wholesale power supply. In broader terms, it refers to the aggregate of electric generating plants, transmission lines, and related-equipment. The term may refer to those facilities within one electric utility, or within a group of utilities in which the transmission lines are interconnected.
BUNKER C FUEL OIL - A very heavy substance, left over after other fuels have been distilled from crude oil. Also called NO. 6 FUEL, it is used in power plants, ships and large heating installations. California's Bunker C fuel oil has high sulfur content, which causes air quality concerns when burned as fuel.
BUSBAR - In electric utility operations, a busbar is a conductor that serves as a common connection for two or more circuits. It may be in the form of metal bars or high-tension cables.
BUTANE - A hydrocarbon gas found in the earth along with natural gas and oil. Butane turns into a liquid when put under pressure. It is sold as bottled gas. It is used to run heaters, stoves and motors, and to help make petrochemicals.
BUY THROUGH - An agreement between utility and customer to import power when the customer's service would otherwise be interrupted.
BUYER - An entity that purchases electrical energy or services from the Power Exchange (PX) or through a bilateral contract on behalf of end-use customers.
CALIFORNIA ENERGY COMMISSION - The state agency established by the Warren-Alquist State Energy Resources Conservation and Development Act in 1974 (Public Resources Code, Sections 25000 et seq.) responsible for energy policy. The Energy Commission's five major areas of responsibilities are:
1. Forecasting future statewide energy needs
2. Licensing power plants sufficient to meet those needs
3. Promoting energy conservation and efficiency measures
4. Developing renewable and alternative energy resources, including providing assistance to develop clean transportation fuels
5. Planning for and directing state response to energy emergencies
Funding for the Commission's activities comes from the Energy Resources Program Account, Federal Petroleum Violation Escrow Account and other sources.
CALIFORNIA ENVIRONMENTAL QUALITY ACT (CEQA - pronounced See' quah) Enacted in 1970 and amended through 1983, established state policy to maintain a high-quality environment in California and set up regulations to inhibit degradation of the environment.
CSE (CALIFORNIA SEASONAL EFFICIENCY) - See See Seasonal Efficiency.
CALIFORNIA PUBLIC UTILITIES COMMISSION (CPUC) - A state agency created by constitutional amendment in 1911 to regulate the rates and services of more than 1,500 privately owned utilities and 20,000 transportation companies. The CPUC is an administrative agency that exercises both legislative and judicial powers; its decisions and orders may be appealed only to the California Supreme Court. The major duties of the CPUC are to regulate privately owned utilities, securing adequate service to the public at rates that are just and reasonable both to customers and shareholders of the utilities; including rates, electricity transmission lines and natural gas pipelines. The CPUC also provides electricity and natural gas forecasting, and analysis and planning of energy supply and resources. Its main headquarters are in San Francisco.
CALIFORNIA UTILITY RESEARCH COUNCIL (CURC) - Public Utilities Code, Sections 9201-9203 requires the California Energy Commission, the California Public Utilities Commission, and the investor-owned utilities (Pacific Gas and Electric Company, Southern California Edison, and San Diego Gas & Electric) to coordinate and promote consistency of research, development and demonstration (RD&D) programs with state energy policy. The CURC provides coordination for and sharing of information on energy RD&D in California to avoid duplication of efforts.
CALL-BACK - A provision included in some power sale contracts that lets the supplier stop delivery when the power is needed to meet certain other obligations.
CALORIE - One energy calorie is equivalent to 4.2 joules. Thus, it takes 500,000 calories of energy to boil a pot of coffee. One food calorie equals 1,000 energy calories.
CALORIE (energy calorie - small "c" - as opposed to food Calorie - capital "C") Any of several approximately equal values of heat, each measured as the quantity of heat require to raise the temperature of 1 gram of water by 1 degree Celsius from a standard initial temperature, esp. from 3.98 degress Celsius. 14.5 degrees Celsius, or 19.5 degrees Celsius, at 1 atmosphere pressure. A calorie is the unit of heat equal to 4.184 joules.
CAPACITY - The amount of electric power for which a generating unit, generating station, or other electrical apparatus is rated either by the user or manufacturer. The term is also used for the total volume of natural gas that can flow through a pipeline over a given amount of time, considering such factors as compression and pipeline size.
There are various types of electricity capacity.:
Dependable Capacity: The systems's ability to carry the electric power for the time inrval and period specific, when related to the characteristics of the load to be supplied. Dependable capacity is determined by such factors as capability, operating power factor, weather, and portion of the load the station is to supply.
Installed (or Nameplate) Capacity: The total manufacturer-rated capacities of equipment such as turbines, generators, condensers, transformers, and other system components.
Peaking Capacity: The capacity of generating equipment intended for operation during the hours of highest daily, weekly or seasonal loads.
Purchased Capacity: The amount of energy and capacity available for purchase from outside the system
Reserve Capacity: Extra generating capacity available to meeet peak or abnormally high demands for power and to generate power during scheduled or unscheduled outages. Units available for service, but not maintained at operating temperature, are termed "cold." those units ready and avaiable for service, though not in actual operation, are termed "hot."
CAPACITY FACTOR - A percentage that tells how much of a power plant's capacity is used over time. For example, typical plant capacity factors range as high as 80 percent for geothermal and 70 percent for cogeneration.
CAPACITY RELEASE - A secondary market for capacity that is contracted by a customer which is not using all of its capacity.
CAPTIVE CUSTOMER - A customer who does not have realistic alternatives to buying power from the local utility, even if that customer had the legal right to buy from competitors.
CAULKING - Material used to make an air-tight seal by filling in cracks, such as those around windows and doors.
CARBON DIOXIDE - A colorless, odorless, non-poisonous gas that is a normal part of the air. Carbon dioxide, also called CO2, is exhaled by humans and animals and is absorbed by green growing things and by the sea.
CARBON MONOXIDE (CO) - A colorless, odorless, highly poisonous gas made up of carbon and oxygen molecules formed by the incomplete combustion of carbon or carbonaceous material, including gasoline. It is a major air pollutant on the basis of weight.
CARCINOGENS - Potential cancer-causing agents in the environment. They include among others: industrial chemical compounds found in food additives, pesticides and fertilizers, drugs, toy, household cleaners, toiletries and paints. Naturally occurring ultraviolet solar radiation is also a carcinogen.
CATALYTIC CRACKING - A refinery process that converts a high-boiling range fraction of petroleum (gas oil) to gasoline, olefin feed for alkylation, distillate, fuel oil and fuel gas by use of a catalyst and heat.
CCR - California Code of Regulations.
CELSIUS - A temperature scale based on the freezing (0 degrees) and boiling (100 degrees) points of water. Abbreviated as C in second and subsequent references in text. Formerly known as Centigrade. To convert Celsius to Fahrenheit, multiply the number by 9, divide by 5, and add 32. For example:
10 degrees Celsius x 9 = 90; 90 / 5 = 18; 18 + 32 = 50 degrees Fahrenheit.
CERTIFICATION - process by which a motor vehicle, motor vehicle engine, or motor vehicle pollution control device satisfies the criteria adopted by the California Air Resources Board (ARB) for the control of specified air contaminants from vehicular sources (Health & Safety Code, Section 39018). Certification constitutes a guarantee by the manufacturer that the engine will meet certain standards at 50,000 miles; if not, it must be replaced or repaired without change.
CFCs (CHLOROFLUOROCARBONS or CHLORINATED FLUOROCARBONS) - A family of artificially produced chemicals receiving much attention for their role in stratospheric ozone depletion. On a per molecule basis, these chemicals are several thousand times more effective as greenhouse gases than carbon dioxide. Since they were introduced in the mid-1930s, CFCs have been used as refrigerants, solvents and in the production of foam material. The 1987 Montreal protocol on CFCs seeks to reduce their production by one-half by the year 1998.
CFM (cubic feet per minute) - A measure of flow rate.
CHEMICAL ENERGY - The energy generated when a chemical compound combusts, decomposes, or transforms to produce new compounds.
CHILLER - A device that cools water, usually to between 40 and 50 degrees Fahrenheit for eventual use in cooling air.
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.
CLEAN FUEL VEHICLE - is frequently incorrectly used interchangeably with "alternative fuel vehicle." Generally, refers to vehicles that use low-emission, clean-burning fuels. Public Resources Code Section 25326 defines clean fuels, for purposes of the section only, as fuels designated by ARB for use in LEVs, ULEVs or ZEVs and include, but are not limited to, electricity, ethanol, hydrogen, liquefied petroleum gas, methanol, natural gas, and reformulated gasoline.
CLERESTORY - A wall with windows that is between two different (roof) levels. The windows are used to provide natural light into a building.
CLIMATE ZONE - A geographical area is the state that has particular weather patterns. These zones are used to determine the type of building standards that are required by law.
CLUNKERS - also known as gross-polluting or super- emitting vehicles, i.e., vehicles that emit far in excess of the emission standards by which the vehicle was certified when it was new.
COAL - Black or brown rock, formed under pressure from organic fossils in prehistoric times, that is mined and burned to produce heat energy.
COAL CONVERSION - Changing coal into synthetic gas or liquid fuels. See GASIFICATION.
COAL OIL - Oil that can be obtained by distilling bituminous coal.
COAL SEAM - A mass of coal, occurring naturally at a particular location, that can be commercially mined.
COAL SLURRY PIPELINE - A pipe system that transports pulverized coal suspended in water.
COP (COEFFICIENT OF PERFORMANCE) - - Used to rate the performance of a heat pump, the COP is the ratio of the rate of useful heat output delivered by the complete heat pump unit (exclusive of supplementary heating) to the corresponding rate of energy input, in consistent units and under specific conditions. [See California Code of Regulations, Title 24, Section 2-1602(c)(4)]
COGENERATOR - Cogenerators use the waste heat created by one process, for example during manufacturing, to produce steam which is used, in turn, to spin a turbine and generate electricity. Cogenerators may also be QFs.
COGENERATION - Cogeneration means the sequential use of energy for the production of electrical and useful thermal energy. The sequence can be thermal use followed by power production or the reverse, subject to the following standards:
(a) At least 5 percent of the cogeneration project's total annual energy output shall be in the form of useful thermal energy.
(b) Where useful thermal energy follows power production, the useful annual power output plus one-half the useful annual thermal energy output equals not less than 42.5 percent of any natural gas and oil energy input.
COKE - A porous solid left over after the incomplete burning of coal or of crude oil.
COKE OVEN GAS - Gas given off by coke ovens. Coke oven gas is interchangeable with goal gas.
COMBINED CYCLE PLANT - An electric generating station that uses waste heat from its gas turbines to produce steam for conventional steam turbines.
COMBINED HYDRONIC SPACE/WATER HEATING - a system in which both space heating and domestic water heating are provided by the same water heater(s).
COMBUSTION Burning - Rapid oxidation, with the release of energy in the form of heat and light.
COMFORT CONDITIONING - The process of treating air to simultaneously control its temperature, humidity, cleanliness, and distribution to meet the comfort requirements of the occupants of the conditioned space.
COMFORT ZONE - The range of temperatures over which the majority of persons feel comfortable (neither too hot nor too cold).
COMPETITIVE TRANSMISSION CHARGE - A non-bypassable charge that customers pay to a utility for the recovery of its stranded costs.
COMMERCIALIZATION - Programs or activities that increase the value or decrease the cost of integrating new products or services into the electricity sector. (See "Sustained Orderly Development.")
COMPRESSED NATURAL GAS (CNG) - natural gas that has been compressed under high pressure, typically between 2,000 and 3,600 pounds per square inch, held in a container. The gas expands when released for use as a fuel.
CONDENSATE - Liquid fuel obtained by burning gas or vapor produced from oil and gas wells.
CONDENSER - A heat exchanger in which the refrigerant, compressed to a hot gas, is condensed to liquid by rejecting heat.
CONDITIONED FLOOR AREA - The floor area of enclosed conditioned spaces on all floors measured from the interior surfaces of exterior partitions for nonresidential buildings and from the exterior surfaces of exterior partitions for residential buildings. [See California Code of Regulations, Title 24, Section 2-5302]
CONDITIONED SPACE - Enclosed space that is either directly conditioned space or indirectly conditioned space. [See California Code of Regulations, Title 24, Section 2-5302]
CONDITIONED SPACE, DIRECTLY -- An enclosed space that is provided with heating equipment that has a capacity exceeding 10 Btus/(hr-ft2), or with cooling equipment that has a capacity exceeding 10 Btus/(hr-ft2). An exception is if the heating and cooling equipment is designed and thermostatically controlled to maintain a process environment temperature less than 65 degrees Fahrenheit or greater than 85 degrees Fahrenheit for the whole space the equipment serves. [See California Code of Regulations, Title 24, Section 2- 5302]
CONDITIONED SPACE, INDIRECTLY --Enclosed space that: (1) has a greater area weighted heat transfer coefficient (u-value) between it and directly conditioned spaces than between it and the outdoors or unconditioned space; (2) has air transferred from directly conditioned space moving through it at a rate exceeding three air changes per hour.
CONDUCTANCE - The quantity of heat, in Btu's, that will flow through one square foot of material in one hour, when there is a 1 degree F temperature difference between both surfaces. Conductance values are given for a specific thickness of material, not per inch thickness.
CONDUCTION - The transfer of heat energy through a material (solid, liquid or gas) by the motion of adjacent atoms and molecules without gross displacement of the particles.
CONDUCTIVITY (k) - The quantity of heat that will flow through one square foot of homogeneous material, one inch thick, in one hour, when there is a temperature difference of one degree Fahrenheit between its surfaces.
CONGESTION - A condition that occurs when insufficient transfer capacity is available to implement all of the preferred schedules simultaneously.
CONGESTION MANAGEMENT - Alleviation of congestion by the ISO.
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.
CONTRACTS FOR DIFFERENCES (CFD) -- A type of bilateral contract where the electric generation seller is paid a fixed amount over time which is a combination of the short-term market price and an adjustment with the purchaser for the difference. For example, a generator may sell a distribution company power for ten years at 6-cents/kilowatt-hour (kWh). That power is bid into Poolco at some low /kWh value (to ensure it is always taken). The seller then gets the market clearing price from the pool and the purchaser pays the producer the difference between the Poolco selling price and 6-cents/kWh (or vice versa if the pool price should go above the contract price).
CONTRACT PATH - The most direct physical transmission tie between two interconnected entities. When utility systems interchange power, the transfer is presumed to take place across the "contract path," notwithstanding the electrical fact that power flow in the network will distribute in accordance with network flow conditions. This term can also mean to arrange for power transfer between systems. (See also Parallel path flow)
CONTINENTAL SHELF - The portion of the sea bottom that slopes gradually from the edge of a continent. Usually defined as areas where water is less than 200 meters or 600 feet deep.
CONTROL AREA - An electric power system, or a combination of electric power systems, to which a common automatic generation control (AGC) is applied to match the power output of generating units within the area to demand. The control area of the ISO is the state of California.
CONTINGENCY PLANNING - The Energy Commission's strategy to respond to impending energy emergencies such as curtailment or shortage of fuel or power because of natural disasters or the result of human or political causes, or a clear threat to public health, safety or welfare. The contingency plan specifies state actions to alleviate the impacts of a possible shortage or disruption of petroleum, natural gas or electricity. The plan is reviewed and updated at least every five years, with the last plan being adopted in 1993. Legislative authority for the California Energy Shortage Contingency Plan is found in Public Resources Code, Section 25216.5.
CONVECTION - Transferring heat by moving air, or transferring heat by means of upward motion of particles of liquid or gas heat from beneath.
CONVECTION - Heat transfer by the movement of fluid.
CONVENTIONAL GAS - Natural gas occurring in nature, as opposed to synthetic gas.
CONVERSION - device or kit by which a conventional fuel vehicle is changed to an alternative fuel vehicle.
CONVERTED VEHICLE - a vehicle originally designed to operate on gasoline that has been modified or altered to run on an alternative fuel.
CONVERSION FUEL FACTOR - A number stating units of one system in corresponding values of another system.
CONVERTER - Any technology that changes the potential energy in a fuel into a different from of energy such as heat or motion. The term also is used to mean an apparatus that changes the quantity or quality of electrical energy.
CONVECTION - Transfer by the movement of fluid.
COOLING CAPACITY, LATENT -- Available refrigerating capacity of an air conditioning unit for removing latent heat from the space to be conditioned.
COOLING CAPACITY, SENSIBLE -- Available refrigerating capacity of an air conditioning unit for removing sensible heat from the space to be conditioned.
COOLING CAPACITY, TOTAL - Available refrigerating capacity of an air conditioner for removing sensible heat and latent heat from the space to be conditioned.
COOLING DEGREE DAY - A unit of measure that indicates how heavy the air conditioning needs are under certain weather conditions.
COOLING LOAD - The rate at which heat must be extracted from a space in order to maintain the desired temperature within the space.
COOLING LOAD TEMPERATURE DIFFERENCE (CLTD) - A value used in cooling load calculations for the effective temperature difference (delta T) across a wall or ceiling, which accounts for the effect of radiant heat as well as the temperature difference.
COOLING TOWER - A device for evaporatively cooling water by contact with air.
CO-OP - This is the commonly used term for a rural electric cooperative. Rural electric cooperatives generate and purchase wholesale power, arrange for the transmission of that power, and then distribute the power to serve the demand of rural customers. Co-ops typically become involved in ancillary services such as energy conservation, load management and other demand-side management programs in order to serve their customers at least cost.
COOPERATIVE (Electric utility) - A joint venture organized by consumers to make electric utility service available in their area.
CORD --A measure of volume, 4 by 4 by 8 feet, used to define amounts of stacked wood available for use as fuel. Burned, a cord of wood produces about 5 million calories of energy.
CORPORATE AVERAGE FUEL ECONOMY (CAFE) - A sales-weighted average fuel mileage calculation, in terms of miles per gallon, based on city and highway fuel economy measurements performed as part of the federal emissions test procedures. CAFE requirements were instituted by the Energy Policy and Conservation Act of 1975 (89 Statute. 902) and modified by the Automobile Fuel Efficiency Act of 1980 (94 Statute. 1821). For major manufacturers, CAFE levels in 1996 are 27.5 miles per gallon for light-duty automobiles. CAFE standards also apply to some light trucks. The Alternative Motor Fuels Act of 1988 allows for an adjusted calculation of the fuel economy of vehicles that can use alternative fuels, including fuel-flexible and dual-fuel vehicles.
CRUDE OIL - Petroleum as found in the earth, before it is refined into oil products. Also called CRUDE.
CRUDE OIL STOCKS - Stocks held at refineries and at pipeline terminals. Does not include stocks held on leases (storage facilities adjacent to the wells). In California, crude oil stocks in 1990 are approximately 18 million barrels on any given day.
CUBIC FOOT - The most common unit of measurement of natural gas volume. It equals the amount of gas required to fill a volume of one cubic foot under stated conditions of temperature, pressure and water vapor. One cubic foot of natural gas has an energy content of approximately 1,000 Btus. One hundred (100) cubic feet equals one therm (100 ft3 = 1 therm).
CURIE - A measure of radioactivity.
DAY-AHEAD SCHEDULE - Day-ahead Schedule A schedule prepared by a Scheduling Coordinator or the ISO before the beginning of a trading day. This schedule indicates the levels of generation and demand scheduled for each settlement period of that trading day.
DAYLIGHTING --The use of sunlight to supplement or replace electric lighting.
DAYLIGHTING CONTROL - A control system that varies the light output of an electric lighting system in response to variations in available daylight.
DEEP MINING Extraction of coal or minerals at depths greater than 1,000 feet. Coal usually is deep-mined at not more than 1,500 feet.
DEGREE DAY - A unit, based upon temperature difference and time, used in estimating fuel consumption and specifying nominal annual heating load of a building. When the mean temperature is less than 65 degrees Fahrenheit the heating degree days are equal to the total number of hours that temperature is less than 65 degrees Fahrenheit for an entire year.
DEINTEGRATION - (See disaggregation)
DELTA - A difference in temperature. Often used in the context of the difference between the design indoor temperature and the outdoor temperature.
DEMAND - The rate at which energy is delivered to loads and scheduling points by generation, transmission or distribution facilities.
DEMAND SITE MANAGEMENT - Planning, implementation, and evaluation of utility-sponsored programs to influence the amount or timing of customers' energy use.
DEMAND (Utility) The level at which electricity or natural gas is delivered to users at a given point in time. Electric demand is expressed in kilowatts.
DEMAND BID - Demand Bid A bid into the PX indicating a quantity of energy or an ancillary service that an eligible customer is willing to purchase and, if relevant, the maximum price that the customer is willing to pay.
DEMAND BILLING The electric capacity requirement for which a large user pays. It may be based on the customer's peak demand during the contract year, on a previous maximum or on an agreed minimum. Measured in kilowatts.
DEMAND CHARGE The sum to be paid by a large electricity consumer for its peak usage level.
DEMAND SIDE MANAGEMENT (DSM) The methods used to manage energy demand including energy efficiency, load management, fuel substitution and load building. See LOAD MANAGEMENT.
DEMONSTRATION - The application and integration of a new product or service into an existing or new system. Most commonly, demonstration involves the construction and operation of a new electric technology interconnected with the electric utility system to demonstrate how it interacts with the system. This includes the impacts the technology may have on the system and the impacts that the larger utility system might have on the functioning of the technology.
DENSITY - The mass of a unit volume of a substance.
(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.
DEPENDABLE CAPACITY The system's ability to carry the electric power for the time interval and period specified. Dependable capacity is determined by such factors as capability, operating power factor and portion of the load the station is to supply.
DEPLETABLE ENERGY SOURCES -- 1) electricity purchased from a public utility 2) energy obtained from burning coal, oil, natural gas or liquefied petroleum gases. [See California Code of Regulations, Title 24, Section 2-5302]
DEREGULATION - The elimination of regulation from a previously regulated industry or sector of an industry.
DERIVATIVES - A specialized security or contract that has no intrinsic overall value, but whose value is based on an underlying security or factor as an index. A generic term that, in the energy field, may include options, futures, forwards, etc.
DIESEL OIL - Fuel for diesel engines obtained from the distillation of petroleum. It is composed chiefly of aliphatic hydrocarbons. Its volatility is similar to that of gas oil. Its efficiency is measured by cetane number.
DIFFUSE RADIATION - Solar radiation, scattered by water vapor, dust and other particles as it passes through the atmosphere, so that it appears to come from the entire sky. Diffuse radiation is higher on hazy or overcast days than on clear days.
DIRECT ACCESS - The ability of a retail customer to purchase commodity electricity directly from the wholesale market rather than through a local distribution utility. (See also Retail Competition)
DIRECT CURRENT (DC) - Electricity that flows continuously in the same direction.
DIRECT ENERGY CONVERSION - Production of electricity from an energy source without transferring the energy to a working fluid or steam. For example, photovoltaic cells transform light directly into electricity. Direct conversion systems have no moving parts and usually produce direct current.
DIRECT EXPANSION - (refrigeration) - Any system that, in operation between an environment where heat is absorbed (heat source), and an environment into which unwanted heat is directed (heat sink) at two different temperatures, is able to absorb heat from the heat source at the lower temperature and reject heat to the heat sink at the higher temperature. The cooling effect is obtained directly from a fluid called a refrigerant that absorbs heat at a low temperature and pressure, and transfers heat at a higher temperature and higher pressure.
DIRECT RADIATION - Radiation that has traveled a straight path from the sun, as opposed to diffuse radiation.
DIRECT SOLAR GAIN - Solar energy collected from the sun (as heat) in a building through windows, walls, skylights, etc.
DIRECTLY CONDITIONED SPACE -- See conditioned space, directly.
DISAGGREGATION - The functional separation of the vertically integrated utility into smaller, individually owned business units (i.e., generation, dispatch/control, transmission, distribution). The terms "deintegration," "disintegration" and "delamination" are sometimes used to mean the same thing. (See also "Divestiture.")
DISPATCH - The operating control of an integrated electric system to: Assign generation to specific generating plants and other sources of supply to effect the most reliable and economical supply as the total of the significant area loads rises or falls. Control operations and maintenance of high-voltage lines, substations and equipment, including administration of safety procedures. Operate the interconnection. Schedule energy transactions with other interconnected electric utilities.
DISSOLVED GAS - Natural gas that can be developed for commercial use, and which is found mixed with oil in naturally occurring underground formations.
DISTRIBUTION - The delivery of electricity to the retail customer's home or business through low voltage distribution lines.
DISTRIBUTED GENERATION - A distributed generation system involves small amounts of generation located on a utility's distribution system for the purpose of meeting local (substation level) peak loads and/or displacing the need to build additional (or upgrade) local distribution lines.
DISTRIBUTION SYSTEM (Electric utility) - The substations, transformers and lines that convey electricity from high-power transmission lines to ultimate consumers. See GRID.
DISTRIBUTION UTILITY (Disco) - The regulated electric utility entity that constructs and maintains the distribution wires connecting the transmission grid to the final customer. The Disco can also perform other services such as aggregating customers, purchasing power supply and transmission services for customers, billing customers and reimbursing suppliers, and offering other regulated or non-regulated energy services to retail customers. The "wires" and "customer service" functions provided by a distribution utility could be split so that two totally separate entities are used to supply these two types of distribution services.
DIVESTITURE - The stripping off of one utility function from the others by selling (spinning-off) or in some other way changing the ownership of the assets related to that function. Most commonly associated with spinning-off generation assets so they are no longer owned by the shareholders that own the transmission and distribution assets. (See also "Disaggregation.")
DOSE - The amount of ionizing radiation energy absorbed per unit mass of irradiated material at a specific location, such as a part of a human body.
DOUBLE GLAZING - Windows having two sheets of glass with an airspace between.
DOWNSTREAM - A term used in the petroleum industry referring to the refining, transportation and marketing side of the business.
DRY BULB TEMPERATURE - A measure of the sensible temperature of air.
DRY HOLE - A drilled well that does not yield gas and/or oil quantities or condition to support commercial production; also applied to gas that has been produced and from which liquid components have been removed.
DRY STEAM - The conventional type of geothermal energy used for electricity production in California. Dry steam captured at the earth's surface is used to run electric turbines. The principal dry steam resource area is the Geysers in Northern California; one of only two known areas in the world for dry steam - the other being Larderello, Italy.
DUAL-DUCT SYSTEM - A central plant heating , ventilation and air conditioning (HVAC ) system that produces conditioned air at two temperatures and humidity levels. The air is then supplied through two independent duct systems to the points of usage where mixing occurs.
DUAL-FUEL or BI-FUEL VEHICLE refers to a vehicle capable of operating on two different fuels, in distinct fueling systems, such as compressed natural gas and gasoline.
DUAL-PANED (double-glazed) - Two panes of glass or other transparent material, separated by a space.
DUCT - A passageway made of sheet metal or other suitable material used for conveying air or other gas at relatively low pressures.
DUMP - Excess hydropower that cannot be stored or conserved. Also know as SPILL ENERGY.
ECONOMIC EFFICIENCY - A term that refers to the optimal production and consumption of goods and services. This generally occurs when prices of products and services reflect their marginal costs. Economic efficiency gains can be achieved through cost reduction, but it is better to think of the concept as actions that promote an increase in overall net value (which includes, but is not limited to, cost reductions).
ECONOMIES OF SALE - Economies of scale exist where the industry exhibits decreasing average long-run costs with size.
ECONOMIZER AIR - A ducting arrangement and automatic control system that allows a heating, ventilation and air conditioning (HVAC) system to supply up to 100 percent outside air to satisfy cooling demands, even if additional mechanical cooling is required.
ECONOMIZER WATER - A system which uses either direct evaporative cooling, or a secondary evaporatively cooled water loop and cooling coil to satisfy cooling loads, even if additional mechanical cooling is required.
ECONOMY ENERGY (Electricity utility) - Electricity purchased by one utility from another to take the place of electricity that would have cost more to produce on the utility's own system.
ECOSYSTEM - The interacting system of biological community and its nonliving environment.
EDISON, THOMAS ALVA - The "father" of the American energy industry, Thomas Edison was an American inventor who was born in 1847 and died in 1931. He patented a total of 1,093 inventions - more than any other person in American history. Among the most important were the incandescent electric light bulb (1879), the phonograph (1877) and the movie projector (1893).
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."
EER - (Energy Efficiency Ratio) the ratio of cooling capacity of an air conditioning unit in Btus per hour to the total electrical input in watts under specified test conditions. California Code of Regulations, Section 1602(c)(6).
EFFICACY, LIGHTING - The ratio of light from a lamp to the electrical power consumed, including ballast losses, expressed as lumens per watt. [See California Code of Regulations, Title 24, Section 2-5302]
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.
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."
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.
ELECTRIC 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.
ELECTRIC UTILITY - Any person or state agency with a monopoly franchise (including any municipality), which sells electric energy to end-use customers; this term includes the Tennessee valley Authority, but does not include other Federal power marketing agency (from EPAct).
ELECTRICITY - A property of the basic particles of matter. A form of energy having magnetic, radiant and chemical effects. Electric current is created by a flow of charged particles (electrons).
ELECTROLYSIS - Breaking a chemical compound down into its elements by passing a direct current through it. Electrolysis of water, for example, produces hydrogen and oxygen.
ELECTROMAGNETIC FIELDS (EMF) - Ordinary every day use of electricity produces magnetic and electric fields. These 60 Hertz fields (fields that go back and forth 60 times a second) are associated with electrical appliances, power lines and wiring in buildings.
ELEMENT - A substance consisting entirely of atoms of the same atomic number.
ELEVATION - 1) The height above sea level (altitude); 2) A geometrical projection, such as a building, on a plane perpendicular to the horizon.
EMBEDDED COSTS EXCEEDING MARKET PRICES (ECEMP) - Embedded costs of utility investments exceeding market prices are: i) costs incurred pursuant to a regulatory or contractual obligation; 2) costs that are reflected in cost-based rates; and 3) cost-based rates that exceed the price of alternatives in the marketplace. ECEMPS may become "stranded costs" where they exceed the amount that can be recovered through the asset's sale. Regulatory questions involve whether such costs should be recovered by utility shareholders and if so, how they should be recovered. "Transition costs" are stranded costs which are charged to utility customers through some type of fee or surcharge after the assets are sold or separated from the vertically-integrated utility. "Stranded assets" are assets which cannot be sold for some reason. The British nuclear plants are an example of stranded assets which no one would buy. (Also referred to as Transition Costs.)
EMERGENCY CORE COOLING SYSTEM (ECCS) - Equipment designed to cool the core of a nuclear reactor in the event of a complete loss of the coolant.
EMISSION STANDARD - The maximum amount of a pollutant legally permitted to be discharged from a single source.
EMISSIVITY - The property of emitting radiation; possessed by all materials to a varying extent.
EMITTANCE - The emissivity of a material, expressed as a fraction. Emittance values range from 0.05 for brightly polished metals to 0.96 for flat black paint.
ENERGY - The capacity for doing work. Forms of energy include: thermal, mechanical, electrical and chemical. Energy may be transformed from one form into another.
ENERGY BUDGET - A requirement in the Building Energy Efficiency Standards that a proposed building be designed to consume no more than a specified number of British thermal units (Btus) per year per square foot of conditioned floor area.
ENERGY CHARGE - The amount of money owed by an electric customer for kilowatt-hours consumed.
ENERGY CONSUMPTION - The amount of energy consumed in the form in which it is acquired by the user. The term excludes electrical generation and distribution losses.
ENERGY/FUEL DIVERSITY - policy that encourages the development of energy technologies to diversify energy supply sources, thus reducing reliance on conventional (petroleum) fuels; applies to all energy sectors.
ENERGY EFFICIENCY - Using less energy/electricity to perform the same function. Programs designed to use electricity more efficiently - doing the same with less. For the purpose of this paper, energy efficiency is distinguished from DSM programs in that the latter are utility-sponsored and -financed, while the former is a broader term not limited to any particular sponsor or funding source. "Energy conservation" is a term which has also been used but it has the connotation of doing without in order to save energy rather than using less energy to do the some thing and so is not used as much today. Many people use these terms interchangeably.
ENERGY EFFICIENCY RATIO (EER) See EER.
ENERGY MANAGEMENT SYSTEM - A control system (often computerized) designed to regulate the energy consumption of a building by controlling the operation of energy consuming systems, such as the heating, ventilation and air conditioning (HVAC), lighting and water heating systems.
ENERGY RESERVES - The portion of total energy resources that is known and can be recovered with presently available technology at an affordable cost.
ENERGY RESOURCES - Everything that could be used by society as a source of energy.
ENERGY RESOURCES PROGRAM ACCOUNT (ERPA) - The state law that directs California electric utility companies to gather a state energy surcharge per kilowatt hour of electricity consumed by a customer. These funds are used for operation of the California Energy Commission. As of January 1, 2004, the surcharge is set at of three-tenths of one mil ($0.0003) per kilowatt-hour
ENERGY SECURITY/FUEL SECURITY - policy that considers the risk of dependence on fuel sources located in remote and unstable regions of the world and the benefits of domestic and diverse fuel sources.
ENTITLEMENT - Electric energy or generating capacity that a utility has a right to access under power exchange or sales agreements.
ENVIRONMENTAL PROTECTION AGENCY (EPA) - A federal agency created in 1970 to permit coordinated governmental action for protection of the environment by systematic abatement and control of pollution through integration or research, monitoring, standards setting and enforcement activities.
ENTHALPY - The quantity of heat necessary to raise the temperature of a substance from one point to a higher temperature. The quantity of heat includes both latent and sensible.
EPA - The Environmental Protection Agency. A federal agency charged with protecting the environment.
EPAct - The Energy Policy Act of 1992 addresses a wide variety of energy issues. The legislation creates a new class of power generators, exempt wholesale generators (EWGs), that are exempt from the provisions of the Public Utilities Holding Company Act of 1935 and grants the authority to FERC to order and condition access by eligible parties to the interconnected transmission grid.
ESCO - Efficiency Service Company. A company that offers to reduce a client's electricity consumption with the cost savings being split with the client.
ETHANOL (also know as Ethyl Alcohol or Grain Alcohol, CH3CH2OH) - a liquid that is produced chemically from ethylene or biologically from the fermentation of various sugars from carbohydrates found in agricultural crops and cellulosic residues from crops or wood. Used in the United States as a gasoline octane enhancer and oxygenate, it increases octane 2.5 to 3.0 numbers at 10 percent concentration. Ethanol can also be used in higher concentration (E85) in vehicles optimized for its use.
ETHYL TERTIARY BUTYL ETHER (ETBE) - an aliphatic ether similar to MTBE. This fuel oxygenate is manufactured by reacting isobutylene with ethanol. Having high octane and low volatility characteristics, ETBE can be added to gasoline up to a level of approximately 17 percent by volume. ETBE is used as an oxygenate in some reformulated gasolines.
ETHYLENE - A colorless gas that burns and is an oil refinery product.
EVAPORATIVE COOLING - Cooling by exchange of latent heat from water sprays, jets of water, or wetted material.
EXCEPTIONAL METHOD - An approved alternative calculation method that analyzes designs, materials, or devices that cannot be adequately modeled using public domain computer programs. Exceptional methods must be submitted to and approved by the California Energy Commission. [See California Code of Regulations, Title 20, Section 1409(b)3] Two examples of exceptional methods are the controlled ventilation crawl space (CVC) credit and the combined hydronic space and water heating method.
EXCHANGE (Electric utility) - Agreements between utilities providing for purchase, sale and trading of power. Usually relates to capacity (kilowatts) but sometimes energy (kilowatt-hours).
EXECUTIVE ORDER NUMBER 6 - A provision under the California Emergency Services Act permits the Governor to establish, by Executive Order Number 6, a state Petroleum Fuels Set-Aside Program after proclamation of an energy emergency.
EXEMPT WHOLESALE GENERATOR (EWG) - Created under the 1992 Energy Policy Act, these wholesale generators are exempt from certain financial and legal restrictions stipulated in the Public Utilities Holding Company Act of 1935.
EXFILTRATION - Air flow outward through a wall, building envelope, etc.
EXHAUST - Air removed deliberately from a space, by a fan or other means, usually to remove contaminants from a location near their source.
EXPORTS (Electric utility) - Power capacity or energy that a utility is required by contract to supply outside of its own service area and not covered by general rate schedules.
EXTRA HIGH VOLTAGE (EHV) - Voltage levels higher than those normally used on transmission lines. Generally EHV is considered to be 345,000 volts or higher.
EV (ELECTRIC VEHICLE) - a vehicle powered by electricity, usually provided by batteries but may also be provided by photovoltaic (solar) cells or a fuel cell.
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.
FEDERAL EMERGENCY MANAGEMENT AGENCY (FEMA) -- The federal agency in charge of disaster recovery in locations that have been declared disaster areas by a state's Governor and the President of the United States.
FEDERAL ENERGY REGULATORY COMMISSION (FERC) -- 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.
FENESTRATION -- In simplest terms, windows or glass doors. Technically fenestration is described as any transparent or translucent material plus any sash, frame, mullion or divider. This includes windows, sliding glass doors, French doors, skylights, curtain walls and garden windows.
FIRM ENERGY -- Power supplies that are guaranteed to be delivered under terms defined by contract.
FISSION -- A release of energy caused by the splitting of an atom's nucleus. This is the energy process used in conventional nuclear power plants to make the heat needed to run steam electric turbines.
FISSIONABLE MATERIAL -- A substance whose atoms can be split by slow neutrons. Uranium-235, plutonium-239 and uranium-233 are fissionable materials.
FLARE GAS -- Unwanted natural gas that is disposed of by burning as it is released from an oil field.
FLAT PLATE -- A device used to collect solar energy. It is a piece of metal painted black on the side facing the sun, to absorb the sun's heat.
FLEXIBLE FUEL VEHICLE (FFV) -- a vehicle that can operate on either alcohol fuels (methanol or ethanol) or regular unleaded gasoline or any combination of the two from the same tank.
FLUE GAS -- Gas that is left over after fuel is burned and which is disposed of through a pipe or stack to the outer air.
FLUIDIZED BED COMBUSTION -- A process for burning powdered coal that is poured in a liquid-like stream with air or gases. The process reduces sulfur dioxide emissions from coal combustion.
FLUORESCENT LAMP -- A tubular electric lamp that is coated on its inner surface with a phosphor and that contains mercury vapor whose bombardment by electrons from the cathode provides ultraviolet light which causes the phosphor to emit visible light either of a selected color or closely approximating daylight.
FLUOROCARBON GASES -- Propellants used in aerosol products and refrigerants that are believed to be causing depletion of the earth's ozone shield. See CFCs.
FOOTCANDLE -- A unit of illuminance on a surface that is one foot from a uniform point source of light of one candle and is equal to one lumen per square foot.
FORCED AIR UNIT (FAU) -- A central furnace equipped with a fan or blower that provides the primary means for circulation of air.
FOSSIL FUEL -- Oil, coal, natural gas or their by-products. Fuel that was formed in the earth in prehistoric times from remains of living-cell organisms.
FRACTIONAL DISTILLATION the process of refining crude oil into various oil products. The various products are separated out in the order of their boiling points.
FRAMING EFFECTS -- The effect of framing (wood or metal studs, joists, beams, etc.) on the overall U-value of a wall, roof, floor, window or other building surface. Framing generally increases the U-Value and decreases the R-Value of insulated surfaces.
FRAMING PERCENTAGE -- The area of actual framing in an envelope assembly divided by the overall area of the envelope assembly. This percentage is used to calculate the overall U-value of an assembly.
FREQUENCY -- The number of cycles which an alternating current moves through in each second. Standard electric utility frequency in the United States is 60 cycles per second, or 60 Hertz.
FUEL -- A substance that can be used to produce heat.
FUEL CELL -- A device or an electrochemical engine with no moving parts that converts the chemical energy of a fuel, such as hydrogen, and an oxidant, such as oxygen, directly into electricity. The principal components of a fuel cell are catalytically activated electrodes for the fuel (anode) and the oxidant (cathode) and an electrolyte to conduct ions between the two electrodes, thus producing electricity.
FUEL GAS -- Synthetic gas used for heating or cooling. It has less energy content than pipeline-quality gas.
FUEL OIL -- Petroleum products that are burned to produce heat or power.
FUEL REPROCESSING (Nuclear) -- The means for obtaining usable, fissionable material from spent reactor fuel.
FUEL ROD (Nuclear) -- A long slender tube that holds fissionable material (fuel) for nuclear reactor use. Fuel rods are assembled into bundles called fuel elements or assemblies, which are loaded individually into the reactor core.
FUEL SECURITY -- See Energy Security.
FUSION ENERGY -- A power source, now under development, based on the release of energy that occurs when atoms are combined under the most extreme heat and pressure. It is the energy process of the sun and the stars.
GAS -- Gaseous fuel (usually natural gas) that is burned to produce heat energy. The word also is used, colloquially, to refer to gasoline.
GAS UTILITY -- any person engaged in, or authorized to engage in, distributing or transporting natural gas, including, but not limited to, any such person who is subject to the regulation of the Public Utilities Commission. GASIFICATION -- The process where biomass fuel is reacted with sub- stoichiometric quantities of air and oxygen usually under high pressure and temperature along with moisture to produce gas which contains hydrogen, methane, carbon monoxide, nitrogen, water and carbon dioxide. The gas can be burned directly in a boiler, or scrubbed and combusted in an engine-generator to produce electricity. The three types of gasification technologies available for biomass fuels are the fixed bed updraft, fixed bed downdraft and fluidized bed gasifiers. Gasification is also the production of synthetic gas from coal.
GASOHOL -- In the United States, gasohol (E10) refers to gasoline that contains 10 percent ethanol by volume. This term was used in the late 1970s and early 1980s but has been replaced in some areas of the country by terms such as E-10, Super Unleaded Plus Ethanol, or Unleaded Plus.
GASOLINE -- A light petroleum product obtained by refining oil, and used as motor vehicle fuel.
GAS SYNTHESIS -- A method producing synthetic gas from coal. Also called the FISCHER-TROPSCH PROCESS.
GENERAL LIGHTING -- Lighting designed to provide a substantially uniform level of illumination throughout an area, exclusive of any provision for special visual tasks or decorative effects. [See California Code of Regulations, Title 24, Section 2-5302]
GENERATING STATION -- A power plant.
GENERATION COMPANY (GENCO) -- A regulated or non-regulated entity (depending upon the industry structure) that operates and maintains existing generating plants. The Genco may own the generation plants or interact with the short term market on behalf of plant owners. In the context of restructuring the market for electricity, Genco is sometimes used to describe a specialized "marketer" for the generating plants formerly owned by a vertically-integrated utility.
GENERATION DISPATCH AND CONTROL -- Aggregating and dispatching (sending off to some location) generation from various generating facilities, providing backups and reliability services. Ancillary services include the provision of reactive power, frequency control, and load following.(Also see "Power Pool" and "Poolco" below.)
GEOTHERMAL ELEMENT -- an element of a county general plan consisting of a statement of geothermal development policies, including a diagram or diagrams and text setting forth objectives, principles, standards, and plan proposals, including a discussion of environmental damages and identification of sensitive environmental areas, including unique wildlife habitat, scenic, residential, and recreational areas, adopted pursuant to Section 65303 of the Government Code. GEOTHERMAL ENERGY -- Natural heat from within the earth, captured for production of electric power, space heating or industrial steam.
GEOTHERMAL GRADIENT -- The change in the earth's temperature with depth. As one goes deeper, the earth becomes hotter.
GEOTHERMAL STEAM -- Steam drawn from deep within the earth.
GIGAWATT (GW) -- 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 in 1988.
GLAZING -- A covering of transparent or translucent material (typically glass or plastic) used for admitting light.
GLOBAL CLIMATE CHANGE -- Gradual changing of global climates due to buildup of carbon dioxide and other greenhouse gases in the earth's atmosphere. Carbon dioxide produced by burning fossil fuels has reached levels greater than what can be absorbed by green plants and the seas.
GREENHOUSE EFFECT -- The presence of trace atmospheric gases make the earth warmer than would direct sunlight alone. These gases (carbon dioxide [CO2], methane [CH4], nitrous oxide [N2O], tropospheric ozone [O3], and water vapor [H2O]) allow visible light and ultraviolet light (shortwave radiation) to pass through the atmosphere and heat the earth's surface. This heat is re-radiated from the earth in form of infrared energy (longwave radiation). The greenhouse gases absorb part of that energy before it escapes into space. This process of trapping the longwave radiation is known as the greenhouse effect. Scientists estimate that without the greenhouse effect, the earth's surface would be roughly 54 degrees Fahrenheit colder than it is today -- too cold to support life as we know it. See GLOBAL CLIMATE CHANGE.
GREENHOUSE EFFECT (relating to buildings) -- The characteristic tendency of some transparent materials (such as glass) to transmit radiation with relatively short wavelengths (such as sunlight) and block radiation of longer wavelengths (such as heat). This tendency leads to a heat build-up within the space enclosed by such a material.
GRID -- A system of interconnected power lines and generators that is managed so that the generators are dispatched as needed to meet the requirements of the customers connected to the grid at various points. Gridco is sometimes used to identify an independent company responsible for the operation of the grid.
GRID -- The electric utility companies' transmission and distribution system that links power plants to customers through high power transmission line service (110 kilovolt [kv] to 765 kv); high voltage primary service for industrial applications and street rail and bus systems (23 kv-138 kv); medium voltage primary service for commercial and industrial applications (4 kv to 35 kv); and secondary service for commercial and residential customers (120 v to 480 v). Grid can also refer to the layout of a gas distribution system of a city or town in which pipes are laid in both directions in the streets and connected at intersections.
GROSS AREA -- The area of a surface including areas not belonging to that surface (such as windows and doors in a wall).
GROSS NATIONAL PRODUCT (GNP) -- The total market value of the goods and services produced by a nation before deduction or depreciation charges and other allowance for capital consumption and is widely used as a measure of economic activity.
HEAT BALANCE - The outdoor temperature at which a building's internal heat gain (from people, lights and machines) is equal to the heat loss through windows, roof and walls.
HEAT CAPACITY - The amount of heat necessary to raise the temperature of a given mass one degree. Heat capacity may be calculated by multiplying the mass by the specific heat.
HEAT ENGINE - An engine that converts heat to mechanical energy.
HEAT GAIN - an increase in the amount of heat contained in a space, resulting from direct solar radiation, heat flow through walls, windows, and other building surfaces, and the heat given off by people, lights, equipment, and other sources.
HEAT LOSS - A decrease in the amount of heat contained in a space, resulting from heat flow through walls, windows, roof and other building surfaces and from exfiltration of warm air.
HEAT PUMP - An air-conditioning unit which is capable of heating by refrigeration, transferring heat from one (often cooler) medium to another (often warmer) medium, and which may or may not include a capability for cooling. This reverse-cycle air conditioner usually provides cooling in summer and heating in winter.
HEAT RATE - A number that tells how efficient a fuel-burning power plant is. The heat rate equals the Btu content of the fuel input divided by the kilowatt-hours of power output.
HEAT STORM - Heat storms occur when temperatures exceed 100 degrees Fahrenheit over a large area for three days in a row. Normal hot temperatures cause electricity demand to increase during the peak summertime hours of 4 to 7 p.m. when air conditioners are straining to overcome the heat. If a hot spell extends to three days or more, however, nighttime temperatures do not cool down, and the thermal mass in homes and buildings retains the heat from previous days. This heat build-up causes air conditioners to turn on earlier and to stay on later in the day. As a result, available electricity supplies are challenged during a higher, wider peak electricity consumption period.
HEAT TRANSFER - Flow of heat energy induced by a temperature difference. Heat flow through a building envelope typically flows from a heated, or hot area to a cooled, or cold area.
HEATING DEGREE DAY - A unit that measure the space heating needs during a given period of time.
HEATING LOAD - The rate at which heat must be added to a space in order to maintain the desired temperature within the space.
HEATING SEASONAL PERFORMANCE FACTOR - A representation of the total heating output of a central air-conditioning heat pump in Btus during its normal usage period for heating, divided by the total electrical energy input in watt-hours during the same period, as determined using the test procedure specified in the California Code of Regulations, Title 20, Section 1603(c).
HEATING VALUE - The amount of heat produced by the complete combustion of a given amount of fuel.
HEAVY WATER - A type of hydrogen atom that may be used as fuel for fusion power plants. Also called DEUTERIUM, it is found in abundance in the seas.
HEDGING CONTRACTS - Contracts which establish future prices and quantities of electricity independent of the short-term market. Derivatives may be used for this purpose. (See Contracts for Differences, Forwards, Futures Market, and Options.)
HELIOCHEMICAL - Using solar radiation to cause chemical reactions.
HELIOTHERMAL - A process that uses the sun's rays to produce heat.
HERTZ - A unit of electromagnetic wave frequency that is equal to one cycle per second. - It is named after Henrich R. Hertz.
HIGH-SULFUR COAL - Coal whose weight is more than one percent sulfur.
HOME ENERGY ASSISTANCE PROGRAM (HEAP) - A centrally operated direct payment program that assists eligible households in offsetting the cost of heating and cooling their homes. Payments are generally made in the form of dual party warrants (checks) made payable to the applicant and their designated utility company. The program is administered by the California Department of Economic Opportunity using federal and state funds. The toll-free number for the HEAP Program is (800) 433-4327. For more information about your utility bills.
HORSEPOWER (HP) - A unit for measuring the rate of doing work. One horsepower equals about three-fourths of a kilowatt (745.7 watts).
HOT - (Colloquial) - The word is sometimes used to describe electric utility lines that are carrying electric currently. It also is used to refer to anything that is highly radioactive.
HOT DRY ROCK - A geothermal resource created when impermeable, subsurface rock structures, typically granite rock 15,000 feet or more below the earth's surface, are heated by geothermal energy. The resource is being investigated as a source of energy production.
HSPF (Heating Seasonal Performance Factor) - A measure of heating efficiency for the total heating output of a central air-conditioning heat pump. Efficiency is derived according to federal test methods by using the total Btus during its normal usage period for heating divided by the total electrical energy input in watt-hours during the same period. California Code of Regulations, Section 2-1602(c)(7).
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.
HYDROELECTRIC SPILL GENERATION - Hydroelectric generation in existence prior to January 1, 1998, that has no storage capacity and that, if backed down, would spill. This term also refers to a hydro resource that has exceeded or has inadequate storage capacity and is spilling, even though generators are operating at full capacity.
HYBRID VEHICLE - Usually a hybrid EV, a vehicle that employs a combustion engine system together with an electric propulsion system. Hybrid technologies expand the usable range of EVs beyond what an all-electric-vehicle can achieve with batteries only.
HYDRONIC HEATING - A system that heats a space using hot water which may be circulated through a convection or fan coil system or through a radiant baseboard or floor system.
HYDROTHERMAL SYSTEMS - Underground reservoirs that produce either dry steam or a mixture of steam and water.
HYGAS - A process that uses water to help produce pipeline-quality gas from coal.
ILEV (Inherently Low Emission Vehicle) -- Term used by federal government for any vehicle that is certified to meet the California Air Resources Board's Low Emission Vehicle (LEV) standards for non-methane organic gases and carbon monoxide, ULEV standards for nitrogen oxides and does not emit any evaporative emissions.
IMPORTS (Electric utility) -- Power capacity or energy obtained by one utility from others under purchase or exchange agreement.
IMPOUNDMENT -- A body of water confined by a dam, dike, floodgate or other artificial barrier.
INCANDESCENT LAMP -- An electric lamp in which a filament is heated by an electric current until it emits visible light.
INDEPENDENT POWER PRODUCER -- An Independent Power Producer (IPP) generates power that is purchased by an electric utility at wholesale prices. The utility then resells this power to end-use customers. Although IPPs generate power, they are not franchised utilities, government agencies or QFs. IPPs usually do not own transmission lines to transmit the power that they generate.
INDIGENOUS ENERGY RESOURCES -- Power and heat derived from sources native to California. These include geothermal, hydro, biomass, solar and wind energy. The term usually is understood to include cogeneration facilities.
INDIRECTLY CONDITIONED SPACE -- See conditioned space, indirectly.
INFILTRATION -- The uncontrolled inward leakage of air through cracks and gaps in the building envelope, especially around windows, doors and duct systems.
INFILTRATION BARRIER -- A material placed on the outside or the inside of exterior wall framing to restrict inward air leakage, while permitting the outward escape of water vapor from the wall cavity. [See California Code of Regulations, Title 24, Section 2-5302]
INFRASTRUCTURE -- generally refers to the recharging and refueling network necessary to successful development, production, commercialization and operation of alternative fuel vehicles, including fuel supply, public and private recharging and refueling facilities, standard specifications for refueling outlets, customer service, education and training, and building code regulations.
INJECTION -- (Petroleum) -- Forcing gas or water into an oil well to increase pressure and cause more oil to come to the surface. See THERMALLY ENHANCED OIL RECOVERY.
IN-SITU COMBUSTION -- An experimental means of recovering hard-to-get petroleum by burning some of the oil in its natural underground reservoir. Also called FIREFLOODING.
IN-SITU GASIFICATION -- Converting coal into synthetic gas at the place where the coal is found in nature.
INSOLATION -- The total amount of solar radiation (direct, diffuse, and reflected) striking a surface exposed to the sky.
INSULATION, THERMAL -- A material having a relatively high resistance of heat flow and used principally to retard heat flow. See R-VALUE.
INTERCHANGE (Electric utility) -- The agreement among interconnected utilities under which they buy, sell and exchange power among themselves. This can, for example, provide for economy energy and emergency power supplies.
INTERCONNECTION (Electric utility) -- The linkage of transmission lines between two utilities, enabling power to be moved in either direction. Interconnections allow the utilities to help contain costs while enhancing system reliability.
INTERESTED PARTY -- any person whom the commission finds and acknowledges as having a real and direct interest in any proceeding or action carried on, under, or as a result of the operation of, this division.
INTERNAL COMBUSTION ENGINE -- An engine in which fuel is burned inside the engine. A car's gasoline engine or rotary engine is an example of a internal combustion engine. It differs from engines having an external furnace, such as a steam engine.
INTERRUPTIBLE SERVICE (Electric utility) -- Electricity supplied under agreements that allow the supplier to curtail or stop service at times.
INTERTIE -- A transmission line that links two or more regional electric power systems.
INVESTOR-OWNED UTILITIES -- A private company that provides a utility, such as water, natural gas or electricity, to a specific service area. The investor-owned utility is regulated by the California Public Utilities Commission. In California the investor owned utilities supplying energy are:
* Canadian Pacific National Corporation
* Pacific Gas and Electric Company
* Pacific Power and Light Company
* San Diego Gas & Electric
* Sierra Pacific Power Company
* Southern California Edison Company
* Southern California Gas Company (The Gas Company)
* Southwest Gas Corporation
ION -- An atom or group of atoms that is electrically charged.
IOU -- An investor owned utility. A company, owned by stockholders for profit, that provides utility services. A designation used to differentiate a utility owned and operated for the benefit of shareholders from municipally owned and operated utilities and rural electric cooperatives.
INTEGRATED RESOURCE PLANNING(IRP) -- A public planning process and framework within which the costs and benefits of both demand- and supply-side resources are evaluated to develop the least-total-cost mix of utility resource options. In many states, IRP includes a means for considering environmental damages caused by electricity supply/transmission and identifying cost-effective energy efficiency and renewable energy alternatives. IRP has become a formal process prescribed by law in some states and under some provisions of the Clean Air Act amendments of 1992.
INTEGRATED RESOURCE PLANNING PRINCIPLES -- The underlying principles of IRP can be distinguished from the formal process of developing an approved utility resource plan for utility investments in supply- and demand-side resources. A primary principle is to provide a framework for comparing a variety of supply- and demand-side and transmission resource costs and attributes outside of the basic provision (or reduction) of electric capacity and energy. These resources may be owned or constructed by any entity and may be acquired through contracts as well as through direct investments. Another principle is the incorporation of risk and uncertainty into the planning analysis. The public participation aspects of IRP allow public and regulatory involvement in the planning rather than the siting stage of project development.
IPP -- INDEPENDENT POWER PRODUCER. An private entity that operates a generation facility and sells power to electric utilities for resale to retail customers.
ISDN -- INTEGRATED SERVICES DIGITAL NETWORK. A 128 Kbps(kilobytes per second) digital telephone service available in many parts of the country though not universally available thatmay be able to substitute for fiber optic cable in every respect except possibly television transmission.
ISO -- INDEPENDENT SYSTEM OPERATOR. 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.
JOULE -- A unit of work or energy equal to the amount of work done when the point of application of force of 1 newton is displaced 1 meter in the direction of the force. It takes 1,055 joules to equal a British thermal unit. It takes about 1 million joules to make a pot of coffee.KEROSENE -- Certain colorless, low-sulfur oil products that burn without producing much smoke.
kBtu -- One-thousand (1,000) Btus.
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.
LANDFILL GAS - Gas generated by the natural degrading and decomposition of municipal solid waste by anaerobic microorganisms in sanitary landfills. The gases produced, carbon dioxide and methane, can be collected by a series of low-level pressure wells and can be processed into a medium Btu gas that can be burned to generate steam or electricity.
LASER - A very intense, uniform beam of electromagnetic radiation. Acronym for Light Amplification by Simulated Emission of Radiation.
LATENT HEAT - A change in the heat content that occurs without a corresponding change in temperature, usually accompanied by a change of state (as from liquid to vapor during evaporation).
LATENT LOAD - The cooling load caused by moisture in the air.
LATITUDE - The angular distance north or south of the equator, measured in degrees of arc.
LAYOFF (Electric utility) - Excess capacity of a generating unit, available for a limited time under the terms of a power sales agreement.
LAY UP - Lay up is another term for cold storage and describes the status of equipment (such as a power plant) that has been placed in storage ("mothballed") for latter use.
LEADED GASOLINE - Gasoline containing tetraethyl lead, an important constituent in antiknock gasoline. Leaded gasoline is no longer sold in the United States.
LOAD CENTERS - A geographical area where large amounts of power are drawn by end-users.
LIFE-CYCLE COST - Amount of money necessary to own, operate and maintain a building over its useful life.
LIFE EXTENSION - A term used to describe capital expenses which reduce operating and maintenance costs associated with continued operation of electric utility boilers. Such boilers usually have a 40 year operating life under normal circumstances.
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.
LIGHT WATER REACTOR (LWR) - A nuclear power unit that uses ordinary water to cool its core. The LWR may be a boiling water reactor or a pressurized water reactor.
LIGNITE - Brownish black coal having qualities in between those of bituminous coal and peat. The texture of the original wood often is visible in lignite.
LIQUEFACTION - The process of making synthetic liquid fuel from coal. The term also is used to mean a method for making large amounts of gasoline and heating oil from petroleum.
LIQUEFIED GASES - Gases that have been or can be changed into liquid form. These include butane, butylene, ethane, ethylene, propane and propylene.
LNG (LIQUEFIED NATURAL GAS) - Natural gas that has been condensed to a liquid, typically by cryogenically cooling the gas to minus 260 degrees Fahrenheit (below zero).
LPG (LIQUEFIED PETROLEUM GAS) - A mixture of gaseous hydrocarbons, mainly propane and butane that change into liquid form under moderate pressure. LPG or propane is commonly used as a fuel for rural homes for space and water heating, as a fuel for barbecues and recreational vehicles, and as a transportation fuel. It is normally created as a by-product of petroleum refining and from natural gas production.
LIQUID BRINE - A type of geothermal energy resource that depends on naturally occurring hot water solution found within the earth. Technology for this novel energy source is being developed in the Salton Sea area in Southern California.
LIQUID PETROLEUM GAS - See LPG.
LOAD - The amount of electric power supplied to meet one or more end user's needs.
LOAD - An end-use device or an end-use customer that consumes power. Load should not be confused with demand, which is the measure of power that a load receives or requires.
LOAD DIVERSITY - The condition that exists when the peak demands of a variety of electric customers occur at different times. This is the objective of "load molding" strategies, ultimately curbing the total capacity requirements of a utility.
LOAD FACTOR - A percent telling the difference between the amount of electricity a consumer used during a given time span and the amount that would have been used if the usage had stayed at the consumer's highest demand level during the whole time. The term also is used to mean the percentage of capacity of an energy facility - such as power plant or gas pipeline -- that is utilized in a given period of time.
LOAD MANAGEMENT - Steps taken to reduce power demand at peak load times or to shift some of it to off-peak times. This may be with reference to peak hours, peak days or peak seasons. The main thing affecting electric peaks is air-conditioning usage, which is therefore a prime target for load management efforts. Load management may be pursued by persuading consumers to modify behavior or by using equipment that regulates some electric consumption.
LOOP FLOW - The difference between scheduled and actual power flows on electric transmission lines.
LOSSES (Electric utility) - Electric energy or capacity that is wasted in the normal operation of a power system. Some kilowatt-hours are lost in the form of waste heat in electrical apparatus such as substation conductors. LINE LOSSES are kilowatts or kilowatt-hours lost in transmission and distribution lines under certain conditions.
LOW-E - A special coating that reduces the emissivity of a window assembly, thereby reducing the heat transfer through the assembly.
LOW EMISSION VEHICLE (LEV) - a vehicle certified by the California Air Resources Board to have emissions from zero to 50,000 miles no higher than 0.075 grams/mile (g/mi) of non-methane organic gases, 3.4 g/mi of carbon monoxide, and 0.2 g/mi of nitrogen oxides. Emissions from 50,000 to 100,000 miles may be slightly higher (See chart in Chapter 2.) LOW-SULFUR COAL - Coal having one percent or less of sulfur by weight.
LOW-SULFUR OIL - Oil having one percent or less of sulfur by weight.
LUMEN - A measure of the amount of light available from a light source equivalent to the light emitted by one candle.
LUMENS/WATT - A measure of the efficacy of a light fixture; the number of lumens output per watt of power consumed.
LUMEN MAINTENANCE CONTROL - An electrical control device designed to vary the electrical consumption of a lighting system in order to maintain a specified illumination level.
LUMINAIRE - A complete lighting unit consisting of a lamp or lamps together with the parts designed to distribute the light, to position and protect the lamps and to connect the lamps to the power supply. California Code of Regulations, Section 2- 1602(h)].
LUX - A unit of illumination equal to the direct illumination on a surface that is everywhere one meter from a uniform point source of one candle; a unit of illumination that is equal to one lumen per square meter. Also see footcandle.
M100 -- 100 percent (neat) methanol used as a motor fuel in dedicated methanol vehicles, such as some heavy-duty truck engines.
MAGMA -- The molten rock and elements that lie below the earthós crust. The heat energy can approach 1,000 degrees Fahrenheit and is generated directly from a shallow molten magma resource and stored in adjacent rock structures. To extract energy from magma resources requires drilling near or directly into a magma chamber and circulating water down the well in a convection- type system. California has two areas that may be magma resource sites: the Mono- Long Valley Caldera and Coso Hot Springs Known Geothermal Resource Areas.
MAGNETO HYDRO DYNAMICS (MHD) -- A means of producing electricity directly by moving liquids or gases through a magnetic field.
MAJOR NATURAL GAS PRODUCER -- any person who produces natural gas in amounts determined by the commission as having a major effect on energy supplies. MAJOR MARKETER -- any person who sells natural gas or oil in amounts determined by the commission as having a major effect on energy supplies.MAJOR OIL PRODUCER -- means any person who produces oil in amount determined by the commission as having a major effect on energy supplies. MANUFACTURED GAS - Gas produced by certain processes from oil, coal or coke.
MARGINAL COST-- The sum that has to be paid the next increment of product of service. The marginal cost of electricity is the price to be paid for kilowatt-hours above and beyond those supplied by presently available generating capacity.
MARKETER -- An agent for generation projects who markets power on behalf of the generator.The marketer may also arrange transmission, firming or other ancillary services as needed. Though a marketer may perform many of the same functions as a broker, the difference is that a marketer represents the generator while a broker acts as a middleman.
MARKET-BASED PRICE -- A price set by the mutual decisions of many buyers and sellers in a competitive market.
MARGINAL COST -- In the utility context, the cost to the utility of providing the next (marginal)kilowatt-hour of electricity, irrespective of sunk costs.
MARKET CLEARING PRICE -- The price at which supply equals demand. The Day Ahead and Hour Ahead Markets.
MARKET PARTICIPANT -- An entity, including a Scheduling Coordinator, who participates in the energy marketplace through the buying, selling, transmission, or distribution of energy or ancillary services into, out of, or through the ISO-controlled grid.
MASTER FILE -- A file maintained by the PX for use in bidding and bid evaluation protocol that contains information on generating units, loads, and other resources eligible to bid into the PX.
MARSH GAS -- A common term for gas that bubbles to the surface of the water in a marsh or swamp. It is colorless, odorless and can be explosive.
MCF -- One thousand cubic feet or natural gas, having an energy value of one million Btu. A typical home might use six MCF in a month.
MECHANICAL SYSTEM -- See HVAC system.
MEGAWATT (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 1,000 typical homes in the Western U.S. (This is a rounding up to 8,760 kWh/year per home based on an average of 8,549 kWh used per household per year [U.S. DOE EIA, 1997 annual per capita electricity consumtpion figures]).
METER -- A device for measuring levels and volumes of a customerós gas and electricity use.
METHANE (CH4) -- the simplest of hydrocarbons and the principal constituent of natural gas. Pure methane has a heating value of 1,1012 Btu per standard cubic foot.
METHANOL (also known as Methyl Alcohol, Wood Alcohol, CH3OH) -- a liquid formed by catalytically combining carbon monoxide (CO) with hydrogen (H2) in a 1:2 ratio, under high temperature and pressure. Commercially it is typically made by steam reforming natural gas. Also formed in the destructive distillation of wood.
METHYL TERTIARY BUTYL ETHER (MTBE) -- an ether manufactured by reacting methanol and isobutylene. The resulting ether has a high octane and low volatility. MTBE is a fuel oxygenate and is permitted in unleaded gasoline up to a level of 15 percent. It is one of the primary ingredients in reformulated gasolines.
METHANE -- A light hydrocarbon that is the main component of natural gas and marsh gas. It is the product of the anaerobic decomposition of organic matter, enteric fermentation in animals and is one of the greenhouse gases. Chemical formula is CH4.
MICROWAVE -- Electromagnetic radiation with wavelengths of a few centimeters. It falls between infrared and radio wavelengths on the electromagnetic spectrum. The radio wave beam can deliver electrical energy over long distances.
MIL -- One-tenth of one cent $0.001.
MINIMUM GENERATION -- Generally, the required minimum generation level of a utility systemós thermal units. Specifically, the lowest level of operation of oil-fired and gas-fired units at which they can be currently available to meet peak load needs.
MONOPOLY -- The only seller with control over market sales.
MONOPSONY -- The only buyer with control over market purchases.
MTBE (METHYL TERTIARY-BUTYL ETHER) -- A clean- burning oxygenate with high octane and low volatility added to unleaded gasoline to reduce carbon monoxide emissions.
MUNICIPAL ELECTRIC UTILITY -- A power utility system owned and operated by a local jurisdiction.
MUNICIPAL SOLID WASTE -- Locally collected garbage, which can be processed and burned to produce energy.
MUNICIPALIZATION -- The process by which a municipal entity assumes responsibility for supplying utility service to its constituents. In supplying electricity, the municipality may generate and distribute the power or purchase wholesale power from other generators and distribute it.
MUNICIPAL UTILITY -- A provider of utility services owned and operated by a municipal government.
NASUCA -- The National Association of Utility Consumer Advocates. NASUCA includes members from 38 states and the District of Columbia. It was formed "to exchange information and take positions on issues affecting utility rates before federal agencies, Congress and the courts.
NATURAL GAS -- Hydrocarbon gas found in the earth, composed of methane, ethane, butane, propane and other gases.
NATURAL GAS VEHICLE -- vehicles that are powered by compressed or liquefied natural gas.
NATURAL MONOPOLY -- A situation where one firm can produce a given level of output at a lower total cost than can any combination of multiple firms. Natural monopolies occur in industries which exhibit decreasing average long-run costs due to size (economies of scale). According to economic theory, a public monopoly governed by regulation is justified when an industry exhibits natural monopoly characteristics.
NCSL -- The National Conference of State Legislatures. A national advisory council which provides services to state legislatures "by bringing together information from all states to forge workable answers to complex policy questions."
NGV (NATURAL GAS VEHICLE) -- vehicles that are powered by compressed or liquefied natural gas.
NATURAL GASOLINE -- A mixture of liquids extracted from natural gas and suitable for blending with ordinary oil-derived gasoline.
NEUTRON -- An uncharged particle found in the nucleus of every atom except that of hydrogen.
NEWTON -- A unit of force. The amount of force it takes to accelerate one kilogram at one meter per second per second.
NON-DEPLETABLE ENERGY SOURCES -- Energy which is not obtained from depletable energy sources. [See California Code of Regulations, Title 24, Section 2-5302]
NONRESIDENTIAL BUILDING -- -- any building which is heated or cooled in its interior, and is of an occupancy type other than Type H, I, or J, as defined in the Uniform Building Code, 1973 edition, as adopted by the International Conference of Building Officials.
NON-FIRM ENERGY -- Electricity that is not required to be delivered or to be taken under the terms of an electric purchase contract.
NOPR -- A Notice of Proposed Rulemaking. A designation used by the FERC for some of its dockets.
NOx -- Oxides of nitrogen that are a chief component of air pollution that can be produced by the burning of fossil fuels. Also called nitrogen oxides.
NRTA - Northwest Regional Transmission Association. A subregional transmission group within the Western Regional Transmission Association.
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.
NUG -- A non-utility generator. A generation facility owned and operated by an entity who is not defined as a utility in that jurisdictional area.
OBLIGATION TO SERVE -- The obligation of a utility to provide electric service to any customer who seeks that service, and is willing to pay the rates set for that service. Traditionally, utilities have assumed the obligation to serve in return for an exclusive monopoly franchise.
OCEAN THERMAL GRADIENT (OTG) -- Temperature differences between deep and surface water. Deep water is likely to be 25 to 45 degrees Fahrenheit colder. The term also refers to experimental technology that could use the temperature differences as a means to produce energy.
OCCUPANCY SENSOR -- A control device that senses the presence of a person in a given space, commonly used to control lighting systems in buildings.
OCTANE -- A rating scale used to grade gasoline as to its antiknock properties. Also any of several isometric liquid paraffin hydrocarbons, C8H18. Normal octane is a colorless liquid found in petroleum boiling at 124.6 degrees Celsius.
OCTANE RATING -- A measure of a gasolineàs resistance to exploding too early in the engine cycle, which causes knocking. The higher the rating, the lower the chance of premature ignition.
OFFROAD -- Any nonstationary device, powered by an internal combustion engine or motor, used primarily off the highways to propel, move, or draw persons or property, and used in any of the following applications: marine vessels, construction/farm equipment, locomotives, utility and lawn and garden equipment, offroad motorcycles, and offhighway vehicles.
OHM --A unit of measure of electrical resistance. One volt can produce a current of one ampere through a resistance of one ohm.
OIL SHALE -- A type of rock containing organic matter that produces large amounts of oil when heated to high temperatures.
OLIGOPOLY -- A few sellers who exert market control overprices.
OPEC -- Acronym for Organization of Petroleum Exporting Countries founded in 1960 for unify and coordinate petroleum polices of the members. Headquarters is in Vienna, Austria.
OPTIONS -- An option is a contractual agreement that gives the holder the right to buy (call option) or sell (put option) a fixed quantity of a security or commodity (for example, a commodity or commodity futures contract), at a fixed price, within a specified period of time. May either be standardized, exchange-traded, and government regulated, or over-the-counter customized and non-regulated.
ORIENTATION -- the position of a building relative to the points of a compass.
ORIGINAL EQUIPMENT MANUFACTURER (OEM) -- refers to the manufacturers of complete vehicles or heavyduty engines, as contrasted with remanufacturers, converters, retrofitters, up-fitters, and repowering or rebuilding contractors who are overhauling engines, adapting or converting vehicles or engines obtained from the OEMs, or exchanging or rebuilding engines in existing vehicles.
OUTAGE (Electric utility) -- An interruption of electric service that is temporary (minutes or hours) and affects a relatively small area (buildings or city blocks). See BLACKOUT.
OUTER CONTINENTAL SHELF (OCS) -- The submerged lands extending from the out limit of the historic territorial sea (typically three miles) to some undefined outer limit, usually a depth of 600 feet. In the United States, this is the portion of the shelf under federal jurisdiction. See CONTINENTAL SHELF.
OUTSIDE AIR -- Air taken from outdoors and not previously circulated through the HVAC system.
OVER GENERATION -- A condition that occurs when total PX participant demand is less that or equal to the sum of regulatory must-take generation, regulatory must-run generation, and reliability must-run generation.
OVERHANG -- Any horizontal projection that serves as a shading element for a window.
OXYGENATE -- a term used in the petroleum industry to denote octane components containing hydrogen, carbon and oxygen in their molecular structure. Includes ethers such as MTBE and ETBE and alcohols such as ethanol or methanol. The oxygenate is a prime ingredient in reformulated gasoline. The increased oxygen content given by oxygenates promotes more complete combustion, thereby reducing tailpipe emissions.
OXIDES OF NITROGEN -- See NOx.
OZONE - A kind of oxygen that has three atoms per molecule instead of the usual two. Ozone is a poisonous gas, but the ozone layer in the upper atmosphere shields life on earth from deadly ultraviolet radiation from space. The molecule contains three oxygen atoms (O3).
PARTIAL LOAD - An electrical demand that uses only part of the electrical power available. [See California Code of Regulations, Title 24, Section 2-5342(e) 2]
PARTICULATE MATTER (PM) - Unburned fuel particles that form smoke or soot and stick to lung tissue when inhaled. A chief component of exhaust emissions from heavy-duty diesel engines.
PASSIVE SOLAR ENERGY - Use of the sun to help meet a building¹s 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.
PBR - PERFORMANCE-BASED REGULATION - Any rate-setting mechanism which attempts to link rewards (generally profits) to desired results or targets. PBR sets rates, or components of rates,for a period of time based on external indices rather than a utility's cost-of-service. Other definitions include light-handed regulation which is less costly and less subject to debate and litigation. A form of rate regulation which provides utilities with better incentives to reduce their costs than does cost-of-service regulation.
PEAK DEMAND - See PEAK LOAD.
PEAKER - A nickname for a power generating station that is normally used to produce extra electricity during peak load times.
PEAK LOAD OR PEAK DEMAND - The electric load that corresponds to a maximum level of electric demand in a specified time period.
PEAK LOAD - The highest electrical demand within a particular period of time. Daily electric peaks on weekdays occur in late afternoon and early evening. Annual peaks occur on hot summer days.
PEAK LOAD POWER PLANT - A power generating station that is normally used to produce extra electricity during peak load times.
PEAKING UNIT - A power generator used by a utility to produce extra electricity during peak load times.
PEAT - A heterogeneous mixture of partly decomposed organic matter that has accumulated in a water saturated environment over a very long period of time. Peat geologically is considered a very young form of coal and has a heating value of 6,600 Btu/pound in situ. California has minor peat resources.
PETROCHEMICALS - Chemicals made from oil.
PETRODOLLARS - Money paid to other countries for oil imported to the United States.
PADD (PETROLEUM ADMINISTRATION FOR DEFENSE DISTRICTS) - The United States is divided by the U.S. Department of Energy into five PADD regions for planning purposes. The states within PADD V are Alaska, Arizona, California, Hawaii, Nevada, Oregon and Washington, which are linked closely by their oil supply network. Since very little petroleum product is export outside the district, PADD V is essentially a self-contained oil supply system with Alaska and California the main producers and California refining the majority of the crude oil consumed in the PADD.
PERM - The measurement of water vapor through different materials measured in perm-inch (mass of water vapor moving through a unit area in unit time).
PETROLEUM - Oil as found it its natural state under the ground.
PG&E - The acronym for Pacific Gas and Electric Company an electric and natural gas utility serving the central and northern California region.
PHOTOCELL - A device that produces an electric reaction to visible radiant energy (light).
PHOTOSYNTHESIS - A process by which green plants change carbon dioxide into oxygen and organic materials. The energy for this process comes from sunlight.
PHOTOVOLTAIC CELL - A semiconductor that converts light directly into electricity.
PIPELINE - A line of pipe with pumping machinery and apparatus (including valves, compressor units, metering stations, regulator stations, etc.) for conveying a liquid or gas.
POOLCO - Poolco refers to a specialized, centrally dispatched spot market power pool that functions as a short-term market. It establishes the short-term market clearing price and provides a system of long-term transmission compensation contracts. It is regulated to provide open access, comparable service and cost recovery. A poolco would make ancillary generation services, including load following, spinning reserve, backup power, and reactive power, available to all market participants on comparable terms. In addition, the Poolco provides settlement mechanisms when differences in contracted volumes exist between buyers and sellers of energy and capacity.
PORTFOLIO MANAGEMENT - The functions of resource planning and procurement under a traditional utility structure. Portfolio management can also be defined as the aggregation and management of a diverse portfolio of supply (and demand-reduction) resources which will act as a hedge against various risks that may affect specific resources (i.e., fuel price fluctuations and certainty of supply, common mode failures, operational reliability, changes in environmental regulations, and the risk of health, safety, and environmental damages that may occur as a result of operating some supply resources). Under a more market-driven power sector with a "powerpool" or POOLCO wholesale market structure, a portfolio manager would: aggregate and manage a diverse portfolio of spot-market purchases, contracts-for-differences, futures contracts and other market-hedging-type contracts and mechanisms.
PCBs (POLYCHLORONATED BIPHENYLS) - A group of organic compounds used in the manufacture of plastics and formerly used as a coolant in electric transformers. In the environment, PCBs are highly toxic to aquatic life. They persist in the environment for long periods of time and are biologically accumulative.
POWER - Electricity for use as energy.
POWER AUTHORITIES - Quasi-governmental agencies that perform all or some of the functions of a public utility.
POWER PLANT (Note: Two separate words, not one word.) - A central station generating facility that produces energy.
POWER POOL - An entity established to coordinate short-term operations to maintain system stability and achieve least-cost dispatch. The dispatch provides backup supplies, short-term excess sales, reactive power support, and spinning reserve. Historically, some of these services were provided on an unpriced basis as part of the members' utility franchise obligations. Coordinating short-term operations includes the aggregation and firming of power from various generators, arranging exchanges between generators, and establishing (or enforcing) the rules of conduct for wholesale transactions. The pool may own, manage and/or operate the transmission lines ("wires") or be an independent entity that manages the transactions between entities. Often,the power pool is not meant to provide transmission access and pricing, or settlement mechanisms if differences between contracted volumes among buyers and sellers exist.
POWER POOL - Two or more interconnected utilities that plan and operate to supply electricity in the most reliable, economical way to meet their combined load.
PPM (PARTS PER MILLION) - The unit commonly used to represent the degree of pollutant concentration where the concentrations are small.
PREFERRED DAY-AHEAD SCHEDULE - A Scheduling Coordinator's preferred schedule for the ISO day-ahead scheduling process.
PREFERRED HOUR-AHEAD SCHEDULE -- A Scheduling Coordinator's preferred schedule for the ISO hour-ahead scheduling process.
PREFERRED SCHEDULE - The initial schedule produced by a Scheduling Coordinator that represents its preferred mix of generation to meet demand. The schedule includes the quantity of output (generators) and consumption (loads), details of any adjustment bids, and the location of each generator and load. The schedule also specifies the quantities and location of trades between the Scheduling Coordinator and all other Scheduling Coordinators, and is balanced with respect to generation, transmission losses, load, and trades.
PRESSURIZED WATER REACTOR (PWR) - A nuclear power unit cooled by water that is pressurized to keep it from boiling when it reaches high temperatures.
PRIMARY FUEL - Fuel consumed in the original production of energy, before conversion takes place.
PROGRAMMABLE CONTROLLER - A device that controls the operation of electrical equipment (such as air conditioning units and lights) according to a preset time schedule.
PROPANE - A gas that is both present in natural gas and refined from crude oil. It is used for heating, lighting and industrial applications. See also LPG.
PROVIDER OF LAST RESORT - A legal obligation(traditionally given to utilities) to provide service to a customer where competitors have decided they do not