Definitions, Sources and Explanatory Notes

 Category:   Petroleum Stocks
 Topic:   Natural Gas Plant Net Stocks

  Definitions

Key Terms Definition
Barrel A unit of volume equal to 42 U.S. gallons.
Butylene (C4H8) An olefinic hydrocarbon recovered from refinery processes.
Ethane (C2H6) A normally gaseous straight-chain hydrocarbon. It is a colorless paraffinic gas that boils at a temperature of -127.48º F. It is extracted from natural gas and refinery gas streams.
Isobutane (C4H10) A normally gaseous branch-chain hydrocarbon. It is a colorless paraffinic gas that boils at a temperature of 10.9º F. It is extracted from natural gas or refinery gas streams.
Liquefied Petroleum Gases (LPG) A group of hydrocarbon-based gases derived from crude oil refining or nautral gas fractionation. For convenience of transportation, these gases are liquefied through pressurization. Historical EIA published LPG series includes: ethane, ethylene, propane, propylene, normal butane, butylene, isobutane, and isobutylene. This may not be consistent with other definitions of LPG which only include propane, normal butane, and isobutane.
Natural Gas Liquids Those hydrocarbons in natural gas that are separated from the gas as liquids through the process of absorption, condensation, adsorption, or other methods in gas processing or cycling plants. Generally such liquids consist of propane and heavier hydrocarbons and are commonly referred to as lease condensate, natural gasoline, and liquefied petroleum gases. Natural gas liquids include natural gas plant liquids (primarily ethane, propane, butane, and isobutane; see Natural Gas Plant Liquids) and lease condensate (primarily pentanes produced from natural gas at lease separators and field facilities; see Lease Condensate).
Natural Gas Processing Plant Facilities designed to recover natural gas liquids from a stream of natural gas that may or may not have passed through lease separators and/or field separation facilities. These facilities control the quality of the natural gas to be marketed. Cycling plants are classified as gas processing plants.
Normal Butane (C4H10) A normally gaseous straight chain hydrocarbon that is a colorless paraffinic gas which boils at a temperature of 31.1 degrees Fahrenheit.
Pentanes Plus A mixture of hydrocarbons, mostly pentanes and heavier, extracted from natural gas. Includes isopentane, natural gasoline, and plant condensate.
Petroleum Administration for Defense (PAD) Districts Geographic aggregations of the 50 States and the District of Columbia into five districts by the Petroleum Administration for Defense in 1950. These districts were originally defined during World War II for purposes of administering oil allocation. Description and maps of PAD Districts and Refining Districts.
Propane (C3H8) A normally gaseous straight-chain hydrocarbon. It is a colorless paraffinic gas that boils at a temperature of -43.67o F. It is extracted from natural gas or refinery gas streams. It includes all products designated in ASTM Specification D1835 and Gas Processors Association Specifications for commercial propane and HD-5 propane.
Stocks Inventories of fuel stored for future use. Stocks are reported as of the last day of the period (e.g., week or month).

For definitions of related energy terms, refer to the EIA Energy Glossary.

  Sources

Energy Information Administration, Form EIA-816, "Monthly Natural Gas Liquids Report".
  • EIA Forms & Instructions .
  • Background, Survey Methodology and Statistical Details .

  •   Explanatory Notes

  • Description and maps of PAD Districts and Refining Districts from the Petroleum Supply Monthly.