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U Gauge
The quantity of heat transmitted per hour through one square foot of a building section (wall, roof, window, etc.) for each degree Fahrenheit of temperature difference between the air on the warm side and the air on the cold side of the building section.
Ultimate Analysis
The determination of the elements contained in a compound, i.e., carbon, hydrogen, oxygen, nitrogen, sulphur, and other compounds.
Ultimate CO2
The maximum theoretical percentage of flue gas CO2 that is possible to produce from the complete combustion of a fuel with the chemically-correct fuel-air ratio.
Ultimate Customer
The customer who purchases gas for consumption and not for resale purposes. See CONSUMER, GAS.
Ultimate Reservoir Capacity
Total volume of gas within a reservoir which exerts a pressure from 0 pounds per square inch gauge pressure to the maximum or ultimate reservoir gauge pressure.
Ultimate Reservoir Pressure
The maximum reservoir pressure permitted by the geological configuration of the reservoir.
Ultimate Strength
Term used to describe the maximum unit stress a material will withstand when subjected to an applied load in a compression, tension, or shear test.
Zone of invisible radiations beyond the violet end of the spectrum of visible radiations. Since UV wavelengths are shorter than the visible, their photons have more energy, enough to initiate some chemical reactions and to degrade most plastics.
Unaccounted for Gas
The difference between the total gas available from all sources, and the total gas accounted for as sales, net interchange, and company use. This difference includes leakage or other actual losses, discrepancies due to meter inaccuracies, variations of temperature and/or pressure, and other variants, particularly due to measurements being made at different times. In cycle billings, an amount of gas supply used but not billed as of the end of a period. See UNBILLED REVENUES. Compare SENDOUT, GAS.
Unassociated Gas
Natural gas unaccompanied by crude oil when produced. Also called non-associated gas or gas well gas.
Unbilled Revenues
Revenues applicable to gas or electricity consumed but not yet billed to the customer because of bimonthly or cycle billing or for other reasons.
The separation of the various components of gas sales, storage, transmission, delivery and etc. into an ala carte menu of services from which a customer may choose only those desired.
Unconventional Fuels Tax Credit
An incentive tax credit applying to a variety of more costly energy production including, for natural gas, coalbed methane, tight sands, and Devonian shale production.
Unconventional Gas
Natural gas that can not be economically produced using current technology.
Underground Storage
Uniform System of Accounts
A list of a company's account numbers and corresponding account titles, together with specific instructions for the use of individual accounts and general instructions as to the basis of accounting. For utilities, Uniform Systems of Accounts have been issued by both the National Association of Regulatory Utility Commissioners (NARUC) and the Federal Energy Regulatory Commission (FERC). These accounts differ between various utilities, i.e., gas versus electric.
A threaded fitting used to couple two runs of pipe together without having to turn or dismantle either run of pipe.
Unit Heater
Unit of Purchase Methodology
For purposes of the CURRENT ADJUSTMENT, a method for computing a pipeline's average projected purchased gas costs derived by dividing the pipeline's total projected purchased gas costs the pipeline anticipates purchasing during the PGA effective period by the quantities of gas used to compute its total projected purchased gas costs, as detailed in Section 154.305 of the Regulations.
Unit of Sales Methodology
For purposes of the CURRENT ADJUSTMENT, a method of computing a pipeline's average projected purchased gas costs derived by dividing the pipeline's total projected purchased gas costs the pipeline anticipates purchasing during the PGA effective period by the quantities of gas the pipeline anticipates selling during the PGA effective period.
Unit-Years of Service
The same as "dollar-years" except expressed in terms of units rather than plant dollars.
United Method
A classification method that allocates 25% of fixed costs to the demand component and 75% to the commodity component of the rate.
Joint operation of several leases, usually for economic or conservation reasons. Frequently a whole pool or field is unitized to prevent unnecessary drilling and to conduct secondary recovery projects.
A term used in connection with Continuing Property Record Unit. Unitization is the process of assigning work order costs to applicable property record units.
Unsaturated Compounds
Any compound having more than one bond between two adjacent atoms; usually carbon atoms and capable of adding other atoms at that point to reduce it to a single bond.
From a reference point, any point located nearer the origin of flow, that is, before the reference point is reached.
Upstream Pipeline
The first pipeline to transport natural gas en route to an inter-connect point for delivery to another pipeline. See DOWNSTREAM PIPELINE.
Use or Lose
A provision which decreases a shipper's right to capacity if the shipper does not use it at a certain level. The purpose of such a provision is to encourage accurate capacity nominations and full pipeline utilization. Because firm shippers pay a reservation charge for capacity, whether or not they fully utilize that capacity, the Commission has found that no use-or-lose provision may apply to firm transportation.
Used and Useful
Rate making principle regarding the timing and inclusion of plant in the rate base.
Utility Gases
Natural gas, manufactured gas, synthetic gas, liquefied petroleum gas-air mixture, or mixtures of any of these gases.
Utility Plant
Includes Plant: In service, Purchased or Sold, In Process of Reclassification, Leased to Others, Held for Future Use, Completed Construction Not Classified, Construction Work in Progress, Plant Acquisition Adjustments and Other Utility Plant. The Uniform System of Accounts prescribes for the deduction of Accumulated Provision for Depreciation and Amortization.
Utility Plant in Service
That portion of a utility's plant which is devoted to the operations of the company. Excludes plant: purchased or sold, in process of reclassification, leased to others, held for future use, under construction, and acquisition adjustments and adjustment accounts, and without deduction of Accumulated Provision for Depreciation and Amortization.
Utility, Gas
A company that is primarily a distributor of natural gas to ultimate customers in a given geographic area.


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