Glossary of Energy Terms

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A B C D E F G H I J K L M N O P Q R S T U V W X-Z Acronyms

Note: No entries for Y or Z.

Letter M

M85 - a blend of 85 percent methanol and 15 percent unleaded regular gasoline, used as a motor fuel.

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 earth's 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 - In the utility context, the cost to the utility of providing the next (marginal)kilowatt-hour of electricity, irrespective of sunk costs.

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.

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.


MEGAWATT (MW) - One-thousand kilowatts (1,000 kW) or one million (1,000,000) watts. One megawatt is enough electrical capacity to power 1,000 average California homes. (Assuming a loading factor of 0.5 and an average California home having a 2-kilowatt peak capacity.)

MEGAWATT HOUR (MWh) - One-thousand kilowatt-hours, or an amount of electrical energy that would supply 1,370 typical homes in the Western U.S. for one month. (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 consumption figures]).

METER - A device for measuring levels and volumes of a customers 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.

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.

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 systems 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.

A B C D E F G H I J K L M N O P Q R S T U V W X-Z Acronyms

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