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Panhandle Formula
A formula for calculating gas flow in large diameter pipelines, particularly at relatively high pressures and velocities. Compare WEYMOUTH FORMULA.
Paper Hearing
A procedure established by the Commission designed to permit the full development of a record for Commission decision, without the need for full adjudication before an Administrative Law Judge. The purpose of "paper hearings" is to shorten the amount of time necessary for the Commission to reach a final decision concerning a complex matter. Generally, the Commission itself requests the filing of information it believes necessary in order to render a decision, and permits parties to file comments on the information provided. "Paper hearings" were first established in Gas Inventory Charge cases.
A white, tasteless, odorless, waxy substance composed of natural hydrocarbons and obtained from petroleum.
Temporarily storing a shipper's excess gas so that shipper doesn't have to sell it at depressed prices.
Partial Looping
A method for increasing carrying capacity of a pipeline by constructing a series of pipe sections parallel to the main pipeline for a portion of the distance between compressor or pump stations and connecting them to the main pipeline at the beginning and end of each segment. This reduces pressure drop in the portions of the pipeline that are "looped" (i.e., with parallel sections), allowing an increased pressure drop in the unlooped sections and, thus, an increased flow rate. Over time, a series of partial loops may be constructed resulting in a complete, second, parallel pipeline. At which time the pipeline will be totally looped.
Partial Participant
A DSM customer who has installed only some of the DSM program measures recommended for the facility.
The unit used by a utility to measure participation in its DSM programs; usually customers or households in the case of residential programs.
Separate and minute particles in a gas stream. Also, those appearing in the atmosphere as a result of chimney effluent. See POLLUTION, ATMOSPHERIC.
Pay Zone
The producing formation.
Payback Period
The time required for the cumulative operational saving of a DSM (or other) option to equal the investment cost of that option.
Payout Ratio
The ratio of cash dividends on common stock to earnings available for common stock.
Peak Day
The one day (24 hours) of maximum system deliveries of gas during a year. Peak day data is used to, among other things, determine the allocation of certain costs between classes of service. The Commission sometimes required allocation based on an average of three continuous days of maximum deliveries (i.e., three day peak). See also DESIGN DAY.
Peak Day Allocation
Peak Day Curtailment
Curtailment imposed on a day-to-day basis during periods of extremely cold weather when demands for gas exceed the maximum daily delivery capability of a pipeline or distribution system. Peak day curtailment is applied independent of seasonal curtailment and does not affect overall authorized volumes to customers under seasonal curtailment. See SEASONAL CURTAILMENT.
Peak Day Design
Peak Day Method
An allocation method used to allocate demand costs to customer classes based on peak day.
Peak Day Sendout
Peak Hour
The one-hour period of greatest total gas sendout or use.
Peak Load
Peak Load
The maximum load consumed or produced by a unit or group of units in a stated period of time.
Peak Responsibility
The load of a customer, a group of customers, or part of a system at the time of occurrence of the system peak.
Peak Shaving
The use of fuels and equipment to generate or manufacture gas to supplement the normal supply of pipeline gas during periods of extremely high demand. This method prevents the expensive alternative of expanding pipeline facilities.
Providing the gas that an LDC or other customer needs to get though an unexpectedly high-demand period.
An accumulation of partially decayed vegetable matter. It is geologically less mature than lignite or coal and has a lower density since it has not been subjected to elevated temperatures and pressures. Btu content per unit volume is substantially less than for coal.
Penetration Rate
The annual rate at which a DSM measure is implemented, as a percentage of the measure's technical potential.
Percentage of Proceeds Sales
Rather than receiving a specified price for raw gas delivered to a gas processing plant, a producer may instead receive a specified price for residue gas and a percentage of the plant proceeds from the sale of the extracted natural gas liquids.
Perfluorocarbon Tracer Technology
The use of tracer elements to measure the air infiltration rates within residential and commercial buildings. A number of tracers and capillary absorption tubes are placed within the facility. Natural air infiltration forces the migration of tracers to the capillary absorption tubes. After a set time period, the capillary absorption tubes are analyzed using a gas chromatograph. The level of tracer found within the capillary absorption tube is indicative of the building's air infiltration rate.
Permanent Set
Any deformation in a piece of plastic (or metal) which remains after the removal of the load which caused the deformation.
A measurement of the ability of a rock to transmit fluid.
A measure of the effectiveness, over time, of a DSM measure, usually represented by the percentage of energy savings that remains each year. A decline in the energy savings of DSM options is usually caused by the following two factors: equipment degradation and consumer behavior.
Persistence Study
A study to assess changes in DSM program load impacts over time. See PERSISTENCE.
An oil, flammable bituminous liquid that may vary from almost colorless to black, occurs in many places in the upper strata of the earth; is a complex mixture of hydrocarbons with small amounts of other substances, and is prepared for use as gasoline, naphtha, or other products by various refining processes.
Phenolic Resin
A synthetic resin produced by the condensation of a phenol with an aldehyde. Phenolic resins form the basis of a class of thermosetting molding materials.
An acronym for Petroleum Industry Data Exchange. The American Petroleum Institute Subcommittee which is an electronic data interchange action group for the oil and gas industry.
An instrument for measuring pressure or compressibility.
A device used to clean the internal surface of a pipeline. Pigs are usually barrel shaped, made of metal, and covered with metal brushes. They may also have rubber or plastic cups and be made entirely of plastic. They are inserted into the pipeline by means of a device called a pig-trap and pushed through the line by pressure of the flowing fluid, usually gas. The forward movement of the pig, together with its rotation, cleans the rust, liquids, and other undesired substances from the pipeline; also called a go-devil.
Pile, Sacrificial
A mass of metal, usually scrap metal, used as an anode when a rectifier is used in cathodic protection. Also, the magnesium and aluminum anodes used in cathodic protection but which do not require an outside impressed voltage.
A small flame which is utilized to ignite the gas at the main burner(s).
Pilot Program
A DSM program that is generally limited in scope or targeted to a select group of customers and is designed to test or build capability to deliver a full scale program. Compare FULL SCALE PROGRAM.
Pilot, Continuous
A pilot that burns without turn-down throughout the entire time the burner assembly is in service, whether the main burner is firing or not.
Pilot, Expanding
A pilot that burns throughout the entire time the burner assembly is in service, whether the main burner is firing or not. Upon a call for heat, the pilot is automatically expanded so as to reliably ignite the main burner. This pilot may be turned down automatically at the end of main burner flame-establishing period.
Pilot, Intermittent
A pilot which is automatically lighted each time there is a call for heat, it burns during the entire period that the main burner is firing.
Pilot, Interrupted
A pilot which is automatically lighted each time there is a call for heat. The pilot fuel is cut off automatically at the end of the main burner flame-establishing period.
Pipe Coating
A corrosion resistant material (such as asphalt or tar), sometimes with an outer wrapping, used to protect pipe.
Pipe Tongs
A hand or power tool for gripping or rotating pipe.
Pipe, Coated
Pipe that has been covered with a corrosion resistant coating or compound (such as asphalt or tar) to prevent corrosion from soil conditions.
Pipe, Direct Burial Plastic
Plastic pipe not protected by a steel sleeve.
Pipe, Drill
In rotary well drilling, the rigid pipe connection between the collar of the drill at the working level and the rotary table on the derrick platform. In addition to transmitting the driving power to the drill bit, the open drill pipe is used to force mud to and through the perforated drill bit for the purpose of cooling and lubricating the bit and picking up the cuttings so that they can be washed to the surface and removed.
All parts of those physical facilities through which gas is moved in transportation, including pipe, valves, and other appurtenances attached to pipe, compressor units, metering stations, regulator stations, delivery stations, holders, and fabricated assemblies. See SYSTEM TYPE.
Pipeline Capacity
The maximum quantity of gas that can be moved through a pipeline system at any given time based on existing service conditions such as available horsepower, pipeline diameter(s), maintenance schedules, regional demand for natural gas, etc.
Pipeline Condensate
A liquid containing lower boiling aliphatic and aromatic hydrocarbons which may be found in natural gas production, transmission, and distribution pipelines. Condensation to a liquid phase is induced by the higher pressure and lower temperature conditions in the pipeline.
Pipeline Fuel
Natural gas consumed in the operation of a natural gas pipeline, primarily in compressors.
Pipeline Marketing Affiliate
Marketer which is a subsidiary of an interstate pipeline.
Pipeline Patrol
A general inspection of the pipeline right of way by foot, airplane, or land vehicle to observe surface conditions and activity along or on the right of way and noting changes in vegetation growth for indication of gas leakage.
Pipeline Peaking Service
Any service provided by a pipeline company to assist its customers in smoothing the fluctuations in their demand for gas.
Pipeline Quality Gas
A term used to designate a fuel gas compatible with natural gas from pipelines. Such a gas can be substituted for methane. With respect to synthetic pipeline gas, a gas that meets the specifications for methane interchangeability.
A conduit for fluids and gases consisting of pipe or tubing with all necessary valves and fittings. a.Pipe. Refers to rigid conduit of iron, steel, copper, plastic, or brass. b.Tubing. Refers to a semi-rigid conduit of steel, copper, plastic, brass, or aluminum.
Piping, Trapped
A system of piping that has a low spot that collects liquid at a point other than a drip location.
Pitot Tube
A small device that can be inserted into a pipe to measure the flow of a liquid or gas. This device is composed of two tubes arranged in such a manner that will allow the measurement of both the velocity and static pressures of the flowing liquid or gas. The difference in these pressures is a function of the flow within the pipe.
Formation of small depressions in a surface due to sand blasting, mechanical gouging, acid etching, or corrosion.
Plant Acquisition Adjustments
Represents the difference between the cost to the utility of plant acquired as operating units or systems by purchase, merger, consolidation, liquidation or otherwise, and the Original Cost (defined herein) of such plant less the amount(s) credited at the time of acquisition to Accumulated Provision for Depreciation and Amortization and Contributions in Aid of Construction.
Plant Protection Gas
Minimum volumes required to prevent physical harm to the plant facilities or danger to plant personnel when such protection cannot be afforded through the use of an alternate fuel. This includes the protection of such material in process as would otherwise be destroyed, but shall not include deliveries required to maintain plant production.
Plant Thermal Reduction (PTR)
The Btu equivalent of the liquid products extracted from the producer's gas plus the portion of plant fuel necessary to extract those liquids, plant flare and other plant losses. When expressed as Mcfs this is referred to as Plant Volume Reduction or PVR.
Plastic Insert
Insertion of a plastic liner through an existing steel service.
Plastic Pipe
A hollow cylinder of a plastic material in which the wall thicknesses are ususally small when compared to the diameter and in which the inside and outside walls are essentially concentric.
Plastic Tubing
Same as plastic pipe except that it is usually of small diameter and sized on the same system commonly used for copper tubing.
A material that contains as an essential ingredient one or more organic polymeric substances of large molecular weight, is solid in its finished state, and, at some stage in its manufacture or processing into finished articles, can be shaped by flow. NOTE: Rubber, textiles, adhesives and paint, which may in some cases meet this definition, are not considered plastics. See ASTM definitions of these terms.
A material incorporated in a plastic to increase its workability, flexibility or distensibility.
An above the water reinforced structure with pipe pile legs extending down into the ocean floor to support the above water structures and equipment installed for the measurement of gas, and for the operation of the offshore pipelines.
Plenum Chamber (Plenum)
Gas or air chamber connected with one or more distributing ducts usually located on a space heater.
An external thread pipe fitting that is inserted into the open end of an internal thread pipe fitting to seal the end of a pipe. Also, sealing a hole in a vessel, such as a pipe or tank, by inserting material in the hole and then securing it. Also refers to the material used to plug the hole.
Plug Back
To seal off the bottom section of a well bore to prevent the inflow of fluid from that portion of the hole. This permits the inflow of oil and gas from the formations above the section so sealed off without contamination of fluids below that depth.
Point Balancing
A process by which the interconnected operators will transfer a quantity greater or less than the confirmed nominations scheduled quantity for various contracts at a point in an attempt to make the total gas received or delivered at the point as close as possible to the scheduled quantity during a specific billing period.
Pollution, Atmospheric
Degradation of atmospheric quality due to heat, particulate, or other products from industrial plants, power plants, refineries, or vehicular engines.
A plastic or resin prepared by the polymerization of butylene as essentially the sole monomer.
A plastic or resin prepared by the polymerization of ethylene as essentially the sole monomer.
A substance consisting of molecules characterized by the repetition (neglecting ends, branch junctions and other minor irregularities) of one or more types of monomeric units. Polymers may be formed by polymerization (addition polymer) or polycondensation (condensation polymer). When two or more monomers are involved, the product is called a copolymer.
A chemical reaction in which the molecules of a monomer are linked together to form polymers. When two or more different monomers are involved, the process is called copolymerization.
A polymer prepared by the polymerization (copolymerization) of olefin(s) as the sole monomer(s).
A polymer prepared by the polymerization of propylene as the sole monomer.
Polypropylene Plastics
Plastics based on polymers made with propylene as essentially the sole monomer.
Polyvinylchloride (PVC)
A polymer prepared by the polymerization of vinyl chloride with or without small amounts of other monomers.
Polyvinylchloride (PVC) Plastics
Plastics made by combining polyvinylchloride with colorants, fillers, plasticizers, stabilizers, lubricants, other polymers, and other compounding ingredients. Not all of these modifiers are used in pipe compounds.
Pool, Oil or Gas
In general, the term "pool" is synonymous with the term "reservoir". However, in certain situations a pool may consist of more than one reservoir; generally in the Appalachian Region where completion, gathering, and metering practices prevent segregating production from individual reservoirs.
Pooling Point
A common market point, generally located at the terminus of a pipeline's production area. Under a Pooling Point transportation arrangement, the shipper is responsible for ensuring that the total nominations of gas received at the pooling point are in balance with the amounts received into the main stream. Volumes are then transported downstream under corresponding transportation arrangements. Such arrangements are designed to increase the receipt point flexibility of the shipper. Also referred to as telescoping points or headstations.
Population Density
The number of buildings or dwelling units within a class location unit of a pipeline.
Population Density Index, One Mile
A number roughly proportional to population density in an area that extends 220 yards on either side of the center line of any continuous one-mile length of pipeline main and used in some cases to determine design and/or test requirements.
Voids in a reservoir rock available for storage of fluids. Measured in percent of rock volume.
Opening in the seat of a slide valve in diaphragm gas meters or an opening in any equipment for the flow of gases or vapors.
Positive Displacement Pump
Pump that delivers a constant volume of fluid per cycle of operation at whatever pressure is necessary, within the design limits of the mechanism of the pump.
Postage Stamp Rates
Flat rates charged for transportation service without regard to distance, as opposed to zone or mileage-based rates.
Postage Stamp Rates
A single rate for the entire system; in contrast to zone or mileage based rates.
Posted Field Price
Price for oil or gas in a given area, set by principal buyers. Price is available to any producer in the area.
Pot Life (Working Life)
The period of time during which a reacting thermosetting composition remains suitable for its intended processing after mixing with reaction-initiating agents.
A measure of the capacity of a well to produce oil or gas. When a well is completed, its productive capacity is determined by an official test. The capacity as shown by this test is known as the well's potential. The allowable rate of production assigned to the well is based in whole or in part on its potential.
Potential Energy
Stored energy. Energy possessing the power of doing work but not actually performing such work.
Potential, Pipe to Soil
Electrical potential of pipe with reference to an electrode placed in the ground.
Power Combustion Furnaces
Furnaces that have a combustion blower, which may be located either upstream or downstream from the heat exchangers. If the blower is located upstream, blowing the combustion air into the heat exchangers, the system is called a forced-draft system. If the blower is downstream, the arrangement is called an induced-draft system. Power combustion systems have been commonly used with outdoor furnaces in the past; however, more indoor furnaces are being designed using this concept.
Powerplant and Industrial Fuel Use Act of 1978 (PI
Legislation prohibiting the use of natural gas and oil in new power plants and major fuel-burning installations. Officially repealed in May 1987.
Pre Tax Return
Is equal to the debt component of the rate of return plus the equity component adjusted upwards to reflect the impact of Federal Income Taxes.
A device to remove fine ash, tars, dusts, or smoke particles from flue gases or other gaseous streams; the device may employ mechanical, electrostatic, chemical means, or a combination of these.
Preferred Stock Dividends or Preferred Dividend
Charges - 330
Preferred Stock or Preferred Capital Stock - 331
Capital stock to which preferences or special rights attach particularly as to dividends and/or proceeds in liquidation.
Pregranted Abandonment
FERC authorization to terminate sales or transportation service automatically upon the expiration of the underlying contract.
Preliminary Determination
A conditional approval issued by the FERC that reviews and authorizes all the terms and conditions of a proposed construction project, except the environmental aspects. A type of semi-certificate approval devised by the Commission to speed construction. Once the preliminary determination is issued, sponsors can line up financing and begin right-of-way acquisition and be ready to go when the lengthy environmental process is completed and they receive unconditional certificate authorization.
Premium on Capital Stock
The excess of the amount received by the company from the sale of an issue of the capital stock over the par or stated value of the stock. A premium also arises when a company issues a stock dividend and the market price of such stock exceeds its par or stated value. In this instance, an amount equal to the difference is transferred from retained earnings to premium on capital stock.
These are payments for gas made to producers when the transmission company is unable to meet its contractual obligations to buy gas at a specified time. After the transmission companies' facilities are completed, the gas previously paid for is obtained from the producer over the period of the contracts as the producers' capacities permit.
Presiding Administrative Law Judge (PALJ)
When expressed with reference to pipe, the force per unit area exerted by the medium in the pipe.
Pressure and Temperature Relief Valve
A relief device activated by pressure and/or temperatures, commonly used on water heaters. (P and T relief valves).
Pressure Base
The standard pressure used in determining a gas volume, expressed in terms of pounds of pressure per square inch, usually 14.73 psia.
Pressure Control
Maintenance of pressure, in all or part of a system, at a predetermined level or within a selected range.
Pressure Differential
Difference in pressure between any two points in a continuous system. Compare PRESSURE DROP.
Pressure Drop
The loss in static pressure of the fluid (air, gas, or water) due to friction or obstruction in pipe, valves, fittings, regulators, burners, appliances, and breeching. See PRESSURE LOSSES.
Pressure Gauge
Pressure Limiting Station
Equipment installed for the purpose of preventing the pressure on a pipeline or distribution system from exceeding some maximum pressure as determined by one or more regulating codes by controlling or restricting the flow of gas when abnormal conditions develop. See PRESSURE RELIEF STATION and PRESSURE REGULATING STATION.
Pressure Loader
Device in which the rate of gas flow controls the operation of a pressure governor or regulator.
Pressure Losses
Losses in static or velocity pressure in a piping system due to friction, eddies, leaks, or improper piping design. See PRESSURE DROP.
Pressure Rating
The estimated maximum pressure that the medium in the pipe can exert continuously with a high degree of certainty that failure of the pipe will not occur.
Pressure Regulating Station
Equipment installed for the purpose of automatically reducing and regulating the pressure in the downstream pipeline or main to which it is connected. Included are piping auxiliary devices such as valves, control instruments, control lines, the enclosures, and ventilating equipment. See PRESSURE LIMITING STATION and PRESSURE RELIEF STATION.
Pressure Regulator
Pressure Relief Station
Equipment installed for the purpose of preventing the pressure on a pipeline or distribution system to which it is connected from exceeding the maximum allowable operating pressure by venting gas to the atmosphere whenever the pressure exceeds this valve.
Pressure, Absolute (PSIA)
Pressure in excess of a perfect vacuum. Absolute pressure is obtained by algebraically adding gauge pressure to atmosphere pressure. Pressures reported in "Atmospheres" are understood to be absolute. Absolute pressure must be used in equations of state and in all gas-law calculations. Gauge pressures below atmospheric pressure are called "vacuum."
Pressure, Atmospheric
The pressure due to the weight of the atmosphere (air and water vapor) on the earth's surface. The average atmospheric pressure at sea level (for scientific purposes) has been defined at 14.696 pounds per square inch absolute.
Pressure, Boiler
Pressure, Bottom Hole
Pressure, Critical
The minimum pressure required to liquefy a gas at its critical temperature.
Pressure, Field
Pressure, Gauge (PSIG)
Pounds per square inch above atmospheric pressure.
Pressure, Maximum Actual Operating
The maximum pressure that occurs during normal operations over a one-year period.
Pressure, Maximum Allowable Operating
The maximum operating pressure at which a system or a device may be operated as determined by regulating codes.
Pressure, Open
Pressure, Standard Service
Pressure, Static
Pressure, Suction
The inlet pressure to a compressor, pump, or fan.
Pressure, Total
The sum of the static pressure and the pressure due to the velocity motion.
Pressure, Trap
Pressure held at the trap or oil and gas separator.
Pressure, Velocity
The pressure which would be exerted by a fluid due to its motion if brought to rest. This is distinguished from the static pressure exerted against walls containing the fluid.
Pressure, Working
Normal operating gauge pressure in a device or system.
Pressure-Decline-Curve Method
A method of estimating nonassociated gas reserves in reservoirs which do not have a water drive.
Preventive Maintenance
Examination of plant and equipment on a schedule basis and the replacement or repair of parts that are worn by prescribed amounts or that are in such condition that further use will involve the risk of their failure while in service. It is designed to prevent operating breakdown.
Price Ceiling
Statutory maximum lawful prices for various categories of natural gas, including gas destined for both the intrastate and interstate markets.
Price Earnings Ratio
Market price divided by the annual earnings per share of common stock. The market price used may be a spot price, or an average of closing or the high and low prices for a period; the earnings are for the corresponding period.
Price Elasticity of Demand
A measurement of the sensitivity of demand to changes in price. Technically, the ratio between the percentage change in volumes demanded and the corresponding percentage change in price.
Primary Air
Air that is mixed with fuel before the mix reaches the ignition zone to enhance combustion.
Prime Mover
Mechanical equipment, such as an engine or turbine, which converts the energy of a fuel or fluid into mechanical power, usually rotational.
In a boiler, the excessive carry-over of fine water particles with the steam due to insufficient steam space, faulty boiler design, or faulty operating conditions. Compare FOAMING.
Prior Period Correction
Restatement of a production month's measurement allocation or contract quantities in subsequent months. Also called prior month's adjustments (i.e., PMA's).
Priorities of Service
A predetermined schedule of service obligations or contracts which specifies where one such service or contract takes precedence over another for deliveries of natural gas.
A feature of federal and state regulatory curtailment plans which ranks end-uses of natural gas. In the event of shortage, low priorities, i.e., boiler load, defer to higher priorities, i.e., human needs.
Pro Forma
Latin for "for the sake of form." Used to describe gas pipeline tariff sheets submitted as part of a certificate application or as part of a tariff filing. When made as part of a tariff filing, pro forma sheets do not contain a proposed effective date and are of no force or effect.
Pro Rata Allocation
A capacity or gas supply allocation methodology under which all customers would receive the same proportion of the natural gas service available as their portion of total volumes contracted for. Compare with FIRST COME, FIRST SERVED.
Probable Life
The total expected service life for survivors at any given age; the sum of the age attained and the remaining life.
Probable Reserves
In mining industries other than petroleum, the amount of reserves estimated to be available once additional development expenditures are incurred.
Process Gas
Gas use for which alternate fuels are not technically feasible, such as in applications requiring precise temperature controls and precise flame characteristics.
Processing Plant
A plant in which liquefiable hydrocarbons, such as propane, butane, ethane, or natural gasoline, which are initially components of the gas stream, are extracted or removed.
A legal entity which processes or treats natural gas in a gas plant of any type.
Any party owning, controlling, managing, or leasing any gas well and/or party who produces in any manner natural gas by taking it from the earth or waters.
Producer Contracted Reserves
The volume of recoverable, salable gas reserves committed to or controlled by the reporting pipeline company as the buyer in gas purchase contracts with independent producers, as sellers, including warranty contracts, and which are used for acts and services for which the company has received certificate authorization from the FERC.
Producer Gas (Also Manufactured Gas)
A combustible gas made in a furnace or apparatus by circulating air or a mixture of air and steam through a layer of incandescent material consisting chiefly of carbon monoxide, hydrogen, and nitrogen.
Producing Sand
A rock stratum that contains recoverable oil or gas.
Producing Zone
The interval of rock actually producing oil or gas.
A functional classification relating to that portion of utility plant used for the purpose of producing gas; or to expenses relating to the operation or maintenance of production plant.
Project Financing
Method for financing projects where a company solicits money by pledging its expected revenues to cover the debt.
Propane (C3H8)
A gas, the molecule of which is composed of three carbon and eight hydrogen atoms. Propane is present in most natural gas and is the first product refined from crude petroleum. It has many industrial uses and may be used for heating and lighting. Contains approximately 2,500 Btu per cubic foot.
Proper and Adequate
As in "proper and adequate" depreciation rate. This is a subjective term.
Property Retired
As applied to plant, means property which has been removed, sold, abandoned, destroyed, or which for any cause has been withdrawn from service.
Proprietary Capital
A group of balance sheet accounts which includes common capital stock, preferred capital stock, other paid-in capital installments received on capital stock, discount on capital stock, capital stock expense, appropriated retained earnings, unappropriated retained earnings, and reacquired capital stock.
The specified sharing of oil and/or gas production among the wells in a particular area. Dividing of consumption into parts and billing each at a different rate; generally, proportioning according to some calculable factor for billing period.
A geographical area which exploration has shown contains sedimentary rocks and structure favorable for the presence of oil or gas.
Proven Acreage
Land under which it is known that gas or oil exists in quantity and condition sufficient to support commercial production.
Proven Reserves
Prover, Bell
A device for testing the accuracy of a gas meter. A quantity of air is collected over water or oil in a calibrated cylindrical bell and then passed through the meter by allowing the bell to sink into the water or oil. A comparison of the measured amount of air passing through the meter and the amount registered on the meter dial gives a measure of meter accuracy.
Prover, Critical-Flow
Device utilizing an orifice for testing meters at a pressure of 20 psig or more by passing gas or air through both the meter and orifice and finally discharging it at a lower pressure which maintains critical-flow (sonic velocity) through the orifice. The time for a given quantity of gas to pass through the meter compared to the orifice standard time corrected for test conditions provides a measure of meter accuracy.
Prover, Low Pressure Flow
An apparatus utilizing an orifice for testing meters at low pressures by passing gas or air through the orifice and meter and finally discharging it to the atmosphere. The time for a given quantity of gas to pass through the meter compared to the orifice standard time corrected for test conditions provides a measure of meter accuracy.
Prover, Piston
A device for testing the accuracy of a gas meter consisting of a movable sealed piston contained in a calibrated cylindrical cavity. The air displaced by the moving piston is passed through the meter and a comparison is made between the volume swept out by the piston and the volume registered by the meter under test.
Prover, Transfer
A device for determining the accuracy of a meter under test by comparing its reading against the reading obtained from a calibrated reference meter connected in series with the meter under test.
Provisions for Deferred Income Taxes
The difference between taxes that would be due (paid) using straight-line depreciation and that actually paid using accelerated depreciation for tax purposes and other temporary differences in the recognition of revenue and expense items for income tax purposes and for financial reporting purposes. When determining a utility's cost of service an allowance is granted for income taxes that is computed using straight-line depreciation. When a utility is using accelerated depreciation for tax purposes this results in the utility receiving greater allowance for taxes than the actual taxes paid in initial years of an asset, and a lower allowance for taxes than actual taxes paid in later years of the asset. The Commission treats such excess income (in initial years) as a return-of-capital, similar to depreciation, and requires the utility to reduce its rate base by the amount of excess income (the deferred taxes). This reduces its profit (return-on-capital) in subsequent years. When the situation is reached in later years where taxes paid exceed the allowance for taxes in the cost of service the Commission allows the rate base to be increased by the amount of the shortfall in income (i.e., the negative deferred taxes). This treatment results in the utility only receiving its allowed rate of return on equity investment over the life of the property and flows the benefit from deferring taxes through to the ratepayer. See SOUTH GEORGIA METHOD and REVERSE SOUTH GEORGIA.
Pounds per square inch.
Pertaining to the state of the atmosphere with reference to moisture.
A device for measuring the humidity in the air, employing a wet bulb and a dry bulb thermometer.
Public Convenience and Necessity
That which is necessary or desirable in the public interest. The Commission must find a particular facility or service "necessary or desirable in the public interest" as a condition for granting a certificate of public convenience and necessity.
Public Interest
Usually intended to mean the interest of the public generally as opposed to the interest of an individual or company.
Public Utility
A business organization performing a service relating to or affecting all of the people within a specified area, usually under provisions of a franchise, charter or "certificate", and subject to special governmental regulations. See SERVICE AREA.
Public Utility Regulatory Policies Act of 1978 (PU
A comprehensive federal law governing aspects of energy production, transportation, and utility regulation.
Pulse Combustion
A series of controlled mini-explosions (pulses) creating a pressure pulse and sustaining combustion through a type of chain reaction. This principle applied to a gas heating or water heating appliance will significantly increase the appliance's operating efficiency due to increased turbulence and the elimination of the need to operate a flue gas blower for venting.
A reinforcing sleeve welded over a coupling.
Purchase Deficiency Methodology
The methodology used under the EQUITABLE SHARING MECHANISM to allocate take-or-pay buyout and buydown costs, to be recovered through fixed charges. Each firm sales customer's fixed charge is determined by comparing its cumulative purchase deficiency with that of the system. The intent is for each customer to bear a portion of take-or-pay responsibility commensurate with its reduced purchases during the period take-or-pay was incurred, as the build-up of take-or-pay liability, and the inability of the pipeline to recover it, resulted from the reduced purchases of its firm sales customers. See EQUITABLE SHARING MECHANISM, DEFICIENCY PERIOD and BASE PERIOD.
Purchased Gas Adjustment (PGA)
A provision approved by the regulatory agency allowing a company to make filings to change its rates, without the usual suspension period, for the purpose of recovering currently the changes in its cost of purchased gas. Pipelines with such tariff provisions are permitted to charge all purchased gas costs, net of storage injections and withdrawals, to a deferred expense account. As gas is sold, the deferred account is credited by an amount equal to the volume of gas sold multiplied by the base average cost and Btu content of gas used in the last rate filing. The difference between the charges and credits to this account is accumulated with interest and billed out to customers over the next annual period as a purchased gas surcharge (positive or negative) adjustment.
Purchased Gas Adjustment Clause
A purchaser is the party who buys the gas from a supplier. A purchaser has the obligation to pay for gas based on the gas purchase contract.
Pure Volumetric
To displace gas, liquids, or foreign matter from piping, tanks, and equipment with other gases or liquids.
Purge Cycle
As applied to electric pilot igniters, the period from the time of automatic closure of the main gas supply by the safety shutoff device to the time the electrical circuit is re-energized.
The act of replacing the atmosphere within a container by an inert substance in such a manner as to prevent the formation of explosive mixtures.
The process by which unwanted impurities, such as hydrogen sulfide, are removed from a gas mixture. Purification of gas is accomplished by two principal methods. The dry method in which the gas is passed through some purifying material such as iron oxide mixed with wood shavings, and the wet method in which the gas is brought in contact with some liquid containing an active purifying agent such as ethanolamine or arsenic trioxide.
Plant Volume Reduction. See PLANT THERMAL REDUCTION.
A common mineral-iron disulfide (FeS2) which has a pale brass-yellow color and metallic luster and is burned in making sulfur dioxide and sulfuric acid. Often called "Fool's Gold".
A chemical reaction brought about by the action of heat.
An instrument for the measurement of high temperatures.


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