Energy terminology · MLC-0117

Energy terms: D (128)

• DamA physical barrier constructed across a river or waterway to control the flow of or raise the level of water...
• Day-ahead and hour-ahead marketsForward markets where electricity quantities and market clearing prices are calculated individually for each...
• Day-ahead scheduleA schedule prepared by a scheduling coordinator or the independent system operator before the beginning of a...
• Daylighting controlsA system of sensors that assesses the amount of daylight and controls lighting or shading devices to maintain...
• DCDirect Current
• Deadweight tonsThe lifting capacity of a ship expressed in long tons (2,240 lbs.), including cargo, commodities, and crew.
• Dealer tank wagon (DTW) salesWholesale sales of gasoline priced on a delivered basis to a retail outlet.
• DecathermTen therms or 1,000,000 Btu.
• DecommissioningRetirement of a nuclear facility, including decontamination and/or dismantlement.
• DecontaminationRemoval of unwanted radioactive or hazardous contamination by a chemical or mechanical process.
• Dedicated energy cropsThe herbaceous (non-woody parts of the plant - the petals, leaves, fruit) and woody primary biomass resources...
• Dedicated reservesThe volume of recoverable, salable gas reserves committed to, controlled by, or possessed by the reporting...
• Dedicated vehicleA vehicle that operates only on an alternative fuel, as when a vehicle is configured to operate on compressed...
• Deepest total depthThe deepest total depth of a given well is the distance from a surface reference point (usually the Kelly...
• Deferred costAn expenditure not recognized as a cost of operation of the period in which incurred, but carried forward to...
• Deferred fuel costsAn expenditure for fuel that is not recognized for bookkeeping practices as a cost in the operating period...
• Deferred income tax (liability)A liability in the balance sheet representing the additional Federal income taxes that would have been due if...
• DeforestationThe net removal of trees from forested land.
• Degasification systemThe methods employed for removing methane from a coal seam that could not otherwise be removed by standard...
• Degradable organic carbonThe portion of organic carbon present in such solid waste as paper, food waste, and yard waste that is...
• Degree DaySee Heating Degree Days; Cooling Degree Days; Population-weighted Degree Days.
• Delayed cokingA process by which heavier crude oil fractions can be thermally decomposed under conditions of elevated...
• DeliverabilityRepresents the number of future years during which a pipeline company can meet its annual requirements for...
• Delivered costThe cost of fuel, including the invoice price of fuel, transportation charges, taxes, commissions, insurance...
• Delivered energyThe amount of energy supplied to the end-use sectors (residential, commercial, industrial, and...
• Delivered (gas)The physical transfer of natural, synthetic, and/or supplemental gas from facilities operated by the...
• Deliveries (electric)Energy generated by one system and delivered to another system through one or more transmission lines.
• Demand bidA bid into the power exchange indicating a quantity of energy or an ancillary service that an eligible...
• Demand chargeThat portion of the consumer's bill for electric service based on the consumer's maximum electric capacity...
• Demand charge creditCompensation received by the buyer when the delivery terms of the contract cannot be met by the seller.
• Demand indicatorA measure of the number of energy-consuming units, or the amount of service or output, for which energy...
• Demand intervalThe time period during which flow of electricity is measured (usually in 15-, 30-, or 60-minute increments.)
• Demand response programsDemand response programs are incentive-based programs that encourage electric power customers to temporarily...
• Demand-meteredHaving a meter to measure peak demand (in addition to total consumption) during a billing period. Demand is...
• Demand-side managementA utility action that reduces or curtails end-use equipment or processes. DSM is often used in order to...
• Demand-side management costsThe costs incurred by the utility to achieve the capacity and energy savings from the Demand-Side Management...
• Demonstrated reserve base (coal)A collective term for the sum of coal in both measured and indicated resource categories of reliability...
• Demonstrated resourcesSame qualifications as identified resources, but include measured and indicated degrees of geologic assurance...
• Demonstration and test vehiclesVehicles operated by a motor vehicle dealer solely for the purpose of promoting motor vehicle sales or...
• DemurrageThe charge paid to the vessel owner or operator for detention of a vessel at the port(s) beyond the time...
• DenaturantPetroleum, typically pentanes plus or conventional motor gasoline, added to fuel ethanol to make it unfit for...
• DenaturedFuel ethanol that is rendered unfit for human consumption by the addition of a petroleum denaturant...
• Densified biomass fuelRaw biomass, primarily wood, that has been condensed into a homogenously sized, energy-dense product, such as...
• Dependable capacityThe load-carrying ability of a station or system under adverse conditions for a specified period of time.
• Depleted resourcesResources that have been mined; include coal recovered, coal lost in mining, and coal reclassified as...
• Depleted storage fieldA sub-surface natural geological reservoir, usually a depleted gas or oil field, used for storing natural gas.
• Depletion allowanceA term for either (1) a periodic assignment to expense of recorded amounts or (2) an allowable income tax...
• Depletion (coal)The subtraction of both tonnage produced and the tonnage lost to mining from identified resources to...
• Depletion factorThe multiplier applied to the tonnage produced to compute depletion. This multiplier takes into account both...
• Depreciation and amortization of property, plant, and equipmentThe monthly provision for depreciation and amortization (applicable to utility property other than electric...
• Depth of deepest productionThe depth of the deepest production is the length of the well bore measured (in feet) from the surface...
• DerateA decrease in the available capacity of an electric generating unit, commonly due to:
• DeregulationThe elimination of some or all regulations from a previously regulated industry or sector of an industry.
• Design electrical rating (capacity) netThe nominal net electrical output of a nuclear unit, as specified by the utility for the purpose of plant...
• Design headThe achieved river, pondage, or reservoir surface height (forebay elevation) that provides the water level to...
• DesulfurizationThe removal of sulfur, as from molten metals, petroleum oil, or flue gases.
• DevelopmentThe preparation of a specific mineral deposit for commercial production; this preparation includes...
• Development costsCosts incurred to obtain access to proved reserves and to provide facilities for extracting, treating...
• Development drillingDrilling done to determine more precisely the size, grade, and configuration of an ore deposit subsequent to...
• Development wellA well drilled within the proved area of an oil or gas reservoir to the depth of a stratigraphic horizon...
• Diesel fuelA fuel composed of distillates obtained in petroleum refining operation or blends of such distillates with...
• Diesel fuel systemDiesel engines are internal combustion engines that burn diesel oil rather than gasoline. Injectors are used...
• Diesel-electric plantA generating station that uses diesel engines to drive its electric generators.
• Diffusive transportThe process by which particles of liquids or gases move from an area of higher concentration to an area of...
• DiluentA blend of light hydrocarbons used to change properties of very heavy hydrocarbons (extra heavy crude oil...
• Direct accessThe ability of a retail customer to purchase electricity or other energy sources directly from a supplier...
• Direct control load managementThe magnitude of customer demand that can be interrupted at the time of the seasonal peak load by direct...
• Direct electricity load controlThe utility installs a radio-controlled device on the HVAC equipment. During periods of particularly heavy...
• Direct labor hoursDirect labor hours worked by all mining employees at a mining operation during the year. Includes hours...
• Direct load controlThis Demand-Side Management category represents the consumer load that can be interrupted at the time of...
• Direct milling costOperating costs directly attributable to the processing of ores or other feed materials, including labor...
• Direct mining costOperating cost directly attributable to the mining of ore, including costs for labor, supervision...
• Direct nonprocess end useThose end uses that may be found on commercial, residential, or other sites, as well as at manufacturing...
• Direct process end useThose end uses that are specific to the carrying out of manufacturing. They include process heating, process...
• Direct useUse of electricity that
• Direct utility costA utility cost that is identified with one of the DSM program categories (e.g. Energy Efficiency or Load...
• Directional (deviated) wellA well purposely deviated from the vertical, using controlled angles to reach an objective location other...
• Direct-use energyEnergy, usually in the form of heat, that is produced and consumed at the final point of use. Examples...
• Discharged fuelIrradiated fuel removed from a nuclear reactor during refueling. Also see Spent Fuel.
• Discrete-delivery energy sourcesEnergy sources that must be delivered to a site.
• DispatchingThe operating control of an integrated electric system involving operations such as (1) the assignment of...
• Disposable incomeThe amount of income and wages a person or household has after taxes to spend or save; also called “personal...
• Disposition, natural gasThe removal of natural, synthetic, and/or supplemental gas, or any components or gaseous mixtures contained...
• Disposition, petroleumA set of categories used to account for how crude oil and petroleum products are transferred, distributed, or...
• Distillate fuel oilA general classification for one of the petroleum fractions produced in conventional distillation operations...
• Distillation unit (atmospheric)The primary distillation unit that processes crude oil (including mixtures of other hydrocarbons) at...
• Distributed generatorA generator that is located close to the particular load that it is intended to serve. General, but...
• Distributed/point-of-use water-heating systemA system for heating hot water, for other than space heating purposes, which is located at more than one...
• DistributionThe delivery of energy to retail customers.
• Distribution provider (electric)Provides and operates the wires between the transmission system and the end-use customer. For those end-use...
• Distribution systemThe portion of the transmission and facilities of an electric system that is dedicated to delivering electric...
• Distribution useNatural gas used as fuel in the respondent's operations.
• DistributorA company primarily engaged in the sale and delivery of natural and/or supplemental gas directly to consumers...
• District chilled waterChilled water from an outside source used as an energy source for cooling in a building. The water is chilled...
• District energyEnergy produced in a centralized plant, other than in an electric power plant, that is consumed or stored as...
• District heatSteam or hot water from an outside source used as an energy source in a building. The steam or hot water is...
• DiversityThe electric utility system's load is made up of many individual loads that make demands upon the system...
• Diversity exchangeAn exchange of capacity or energy, or both, between systems whose peak loads occur at different times.
• DivestitureThe stripping off of one utility function from the others by selling (spinning-off) or in some other way...
• DocketA formal record of a Federal Energy Regulatory Commission proceeding. These records are available for...
• DOEDepartment of Energy.
• Domestic crude oilCrude oil produced in the United States including the Outer Continental Shelf (OCS).
• Domestic inland consumptionDomestic inland consumption is the sum of all refined petroleum products supplied for domestic use (excludes...
• Domestic uranium industryCollectively, those businesses (whether U.S. or foreign-based) that operate under the laws and regulations...
• Domestic vehicle producerAn Original Vehicle Manufacturer that assembles vehicles in the United States for domestic use. The term...
• Double circuit lineA transmission line having two separate circuits. Because each carries three-phase power, at least six...
• Drainage basinThe land drained by a river system.
• DrawdownThe lowering of the water level of a reservoir as a result of withdrawing water.
• Drawdown (maximum)The distance that the water surface of the reservoir is lowered from the normal full elevation to the lowest...
• DRBDemonstrated Reserve Base
• Dredge miningA method of recovering coal from rivers or streams.
• Drift mineA mine that opens horizontally into the coal bed or coal outcrop.
• DrillingThe act of boring a hole (1) to determine whether minerals are present in commercially recoverable quantities...
• Drilling and equipping of wellsThe drilling and equipping of wells through completion of the "christmas tree."
• Drilling arrangementA contractual agreement under which a working interest owner (assignor) assigns a part of a working interest...
• Dry bottom boilerNo slag tanks at furnace throat area. The throat area is clear. Bottom ash drops through the throat to the...
• Dry (coal) basisCoal quality data calculated to at heoretical basis in which no moisture is associated with the sample. This...
• Dry holeAn exploratory or development well found to be incapable of producing either oil or gas in sufficient...
• Dry hole chargeThe charge-off to expense of a previously capitalized cost upon the conclusion of an unsuccessful drilling...
• Dry hole contributionA payment (either in cash or acreage) that is required by agreement only if a test well is unsuccessful and...
• Dry natural gasNatural gas which remains after: 1) the liquefiable hydrocarbon portion has been removed from the gas stream...
• Dry natural gas productionThe process of producing consumer-grade natural gas. Natural gas withdrawn from reservoirs is reduced by...
• DSMDemand-Side Management
• DTWDealer Tank Wagon
• Dual fuel vehicle (1)A motor vehicle that is capable of operating on an alternative fuel and on gasoline or diesel fuel. These...
• Dual fuel vehicle (2)A motor vehicle that is capable of operating on an alternative fuel and on gasoline or diesel fuel. This term...
• Dual-fired unitA generating unit that can produce electricity using two or more input fuels. In some of these units, only...
• Dump energyEnergy generated in a hydroelectric plant by water that cannot be stored or conserved and which energy is in...

128 of 2,515 terms in Energy terminology (MLC-0117). Request the full dataset.