D
Data Communications
Synonym: Computer Electronic Data Interchange
Definition: Electronically conveying information from a source to a
destination over communication media. Data
communication includes management and control of
connections and the information transferred.
Decontrol
Synonym:
Definition: The act of ending federal control over the wellhead
price of new natural gas sold in interstate commerce.
Dedication of Reserves
Synonym:
Definition: The assurance of an adequate supply of natural gas
reserves. Usually accomplished by a gas purchase
contract between a natural gas producer and the buyer.
Whereby reserves are committed in a quantity sufficient
to serve the market volume for the term of the contract.
Dekatherm
Synonym: Dth, MMBtu
Definition: A unit of heat equal to 1,000,000 Btus (1MMBtu); the
thermal equivalent of 1,000 cubic feet of gas with a
heat content of 1,000 Btus per cubic foot.
Deliverability
Synonym:
Definition: The volume of gas a well, field, pipeline or
distribution system can supply in a given period of
time.
Delivery
Synonym: Redelivery
Definition: The quantity of gas transferred from the transporter to
the shipper or on behalf of the shipper to a downstream
transportation operator or consumer. From the
transporter's point of view, a delivery is gas exiting
its system.
Delivery Point
Synonym:
Definition: A point at which gas leaves a transporter's system,
completing a sales or transportation service transaction
between the pipeline company and a sales or
transportation service customer.
Demand
Synonym:
Definition: The rate at which gas is delivered to or by a system,
part of a system or a piece of equipment, expressed in
cubic feet, therms or multiples thereof, for a
designated period of time.
Demand, Average
Synonym:
Definition: The demand on a system or any of its parts over an
interval of time, determined by dividing the total
quantity of gas by the number of units of time in the
interval.
Demand, Billing
Synonym:
Definition: The demand upon which billing to a customer is based,
as specified in a rate schedule or contract. It may be
based on the contract year, a contract minimum or a
previous maximum, and therefore does not necessarily
coincide with the actual measured demand of the billing
period.
Demand Charge
Synonym:
Definition: Transaction cost reflecting the reservation of capacity
from a gas seller, pipeline or LDC, not the volumes
actually purchased or transported. Ideally, it should
cover the cost to the seller/pipeline/LDC of providing
the capacity to deliver the user's maximum demand.
Demand Day
Synonym:
Definition: That 24-hour period specified by a supplier-user
contract for purposes of determining the purchaser's
daily quantity of gas used. This term is primarily used
in pipeline-LDC agreements.
Department of Energy
Synonym: DOE
Definition: The Department of Energy is the twelfth Cabinet
Position, and it consists of the Office of the Secretary
of Energy and the Federal Energy Regulatory Commission.
Deregulation
Synonym:
Definition: The act of removing or modifying principles, rules or
laws designed to control or govern behavior. For
example, the Natural Gas Policy Act, 1978, provided for
phased deregulation of natural gas wellhead prices. As
a result, producers and others may sell certain types of
gas to any willing purchaser without being subjected to
federal regulation over market entry, market exit or
price.
Design Day
Synonym:
Definition: A 24-hour period of demand which is used as a basis for
planning gas capacity requirements.
Design Pressure
Synonym: MOP, MAOP
Definition: The maximum operating pressure permitted by various
codes, as determined by the design procedures applicable
to the material and location involved.
Direct Billing
Synonym:
Definition: A method for the recovery of costs, apart from the
usual Demand and Commodity charges, that guarantees
recovery of the amounts billed. This method has been
used for the recovery of a portion of take-or-pay
buy-out costs.
Direct Customer
Synonym:
Definition: A company that purchases gas for its own use directly
from a pipeline company, producer, shipper, or agent
other than an LDC.
Direct Sale
Synonym:
Definition: Contract sale of natural gas by producer or pipeline to
an end-user or LDC, as opposed to selling to or buying
from a pipeline.
Discount
Synonym:
Definition: A rate charged for a transportation service that is less
than the maximum rate stated in the transporter's
approved FERC Gas Tariff.
Displacement
Synonym:
Definition: The method by which equivalent volumes of gas are
delivered from one point on a pipeline to another,
without the physical movement of gas from the first
point to the second.
Dispatching
Synonym: Gas Control
Definition: The control of gas flow in a system, involving the
assignment of load to the various sources of supply to
meet the desired objectives.
Distance Sensitive Tolls
Synonym:
Definition: Pipeline Tolls which have been determined using distance
factors when allocating the Cost of Service.
Distribution, Gas
Synonym:
Definition: The act or process of distributing gas from the city
gate or plant to the consumers.
Distribution Company, Gas
Synonym: LDC
Definition: Company which obtains the major portion of its gas
operating revenues from the operation of a retail gas
distribution system, and which operates no transmission
system other than incidental connections within its own
system or to the system of another company.
Distribution System, Gas
See System, Distribution
Diversion
Synonym:
Definition: The practice of shippers holding rights to divert a
volume of gas either upstream or downstream of a
contractual redelivery point.
Downstream
Synonym:
Definition: Any point in the direction of flow of a liquid or gas
from the reference point.
Downstream Pipeline
Synonym:
Definition: The pipeline receiving natural gas at a pipeline
interconnect point.