Glossary

Energy glossary

747 definitions · page 8 of 13.

LIQUEFIED GASES: Gases that have been or can be changed into liquid form. These include butane, butylene, ethane, ethylene, propane and propylene.
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.
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).
LOAD: The amount of electric power supplied to meet one or more end user's needs.
LOAD CENTERS: A geographical area where large amounts of power are drawn by end-users.
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…
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…
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…
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…
LOW-E - A: special coating that reduces the emissivity of a window assembly, thereby reducing the heat transfer through the assembly.
LOW-SULFUR OIL: Oil having one percent or less of sulfur by weight.
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…
LUMEN: A measure of the amount of light available from a light source equivalent to the light emitted by one candle.
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.
LUMENS WATT: A measure of the efficacy of a light fixture; the number of lumens output per watt of power consumed.
LUMENS/WATT: A measure of the efficacy of a light fixture; the number of lumens output per watt of power consumed.
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.
M85: a blend of 85 percent methanol and 15 percent unleaded regular gasoline, used as a motor fuel.
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…
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…
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.
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.
MARKET-BASED PRICE: A price set by the mutual decisions of many buyers and sellers in a competitive market.
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…
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.
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.
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.
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…
METER: A device for measuring levels and volumes of a customerós gas and electricity use.
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.
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.
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…
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.
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.
MUNICIPAL UTILITY: A provider of utility services owned and operated by a municipal government.
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…
NARUC: the national association of regulatory utility commissioners. An advisory council composed of governmental agencies of the fifty States, the District of Columbia, Puerto Rico and the Virgin Islands engaged in the regulation of utilities and carriers. "The…
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…
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 GASOLINE: A mixture of liquids extracted from natural gas and suitable for blending with ordinary oil-derived gasoline.
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)…
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."
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.
NGV (NATURAL GAS VEHICLE): vehicles that are powered by compressed or liquefied natural gas.