Definitions, Sources and Explanatory Notes

 Category:   Petroleum Refining & Processing
 Topic:   Weekly Inputs & Utilization


Key Terms Definition
All Other Motor Gasoline Blending Components Naphthas (e.g. straight-run gasoline, alkylate, reformate, benzene, toluene, xylene) used for blending or compounding into finished motor gasoline. Includes receipts and inputs of Gasoline Treated as Blendstock (GTAB). Excludes conventional blendstock for oxygenate blending (CBOB), reformulated blendstock for oxygenate blending, oxygenates (e.g. fuel ethanol and methyl tertiary butyl ether), butane, and pentanes plus.
Barrel A unit of volume equal to 42 U.S. gallons.
Blending Plant A facility which has no refining capability but is either capable of producing finished motor gasoline through mechanical blending or blends oxygenates with motor gasoline.
Conventional Blendstock for Oxygenate Blending (CBOB) Motor gasoline blending components intended for blending with oxygenates to produce finished conventional motor gasoline.
Crude Oil A mixture of hydrocarbons that exists in liquid phase in natural underground reservoirs and remains liquid at atmospheric pressure after passing through surface separating facilities. Depending upon the characteristics of the crude stream, it may also include:
  • Small amounts of hydrocarbons that exist in gaseous phase in natural underground reservoirs but are liquid at atmospheric pressure after being recovered from oil well (casinghead) gas in lease separators and are subsequently commingled with the crude stream without being separately measured. Lease condensate recovered as a liquid from natural gas wells in lease or field separation facilities and later mixed into the crude stream is also included;
  • Small amounts of nonhydrocarbons produced with the oil, such as sulfur and various metals;
  • Drip gases, and liquid hydrocarbons produced from tar sands, oil sands, gilsonite, and oil shale.

  • Liquids produced at natural gas processing plants are excluded. Crude oil is refined to produce a wide array of petroleum products, including heating oils; gasoline, diesel and jet fuels; lubricants; asphalt; ethane, propane, and butane; and many other products used for their energy or chemical content.
    Crude Oil Input The total crude oil put into processing units at refineries.
    Fuel Ethanol An anhydrous alcohol (ethanol with less than 1% water) intended for gasoline blending as described in the Oxygenates definition.
    Gasoline Treated as Blendstock (GTAB) Non-certified Foreign Refinery gasoline classified by an importer as blendstock to be either blended or reclassified with respect to reformulated or conventional gasoline. GTAB was classified on EIA surveys as either reformulated or conventional based on emissions performance and the intended end use in data through the end of December 2009. Designation of GTAB as reformulated or conventional was discontinued beginning with data for January 2010. GTAB was reported as a single product beginning with data for January 2010. GTAB data for January 2010 and later months is presented as conventional motor gasoline blending components when reported as a subset of motor gasoline blending components.
    Gross Inputs The crude oil, unfinished oils, and natural gas plant liquids put into atmospheric crude oil distillation units.
    Motor Gasoline Blending Mechanical mixing of motor gasoline blending components, and oxygenates when required, to produce finished motor gasoline. Finished motor gasoline may be further mixed with other motor gasoline blending components or oxygenates, resulting in increased volumes of finished motor gasoline and/or changes in the formulation of finished motor gasoline (e.g., conventional motor gasoline mixed with MTBE to produce oxygenated motor gasoline).
    Motor Gasoline Blending Components Naphthas (e.g., straight-run gasoline, alkylate, reformate, benzene, toluene, xylene) used for blending or compounding into finished motor gasoline. These components include reformulated gasoline blendstock for oxygenate blending (RBOB) but exclude oxygenates (alcohols, ethers), butane, and pentanes plus. Note: Oxygenates are reported as individual components and are included in the total for other hydrocarbons, hydrogens, and oxygenates.
    Operable Capacity The amount of capacity that, at the beginning of the period, is in operation; not in operation and not under active repair, but capable of being placed in operation within 30 days; or not in operation but under active repair that can be completed within 90 days. Operable capacity is the sum of the operating and idle capacity and is measured in barrels per calendar day or barrels per stream day.
    Oxygenates Substances which, when added to gasoline, increase the amount of oxygen in that gasoline blend. Ethanol, Methyl Tertiary Butyl Ether (MTBE), Ethyl Tertiary Butyl Ether (ETBE), and methanol are common oxygenates.
  • Fuel Ethanol: Blends of up to 10 percent by volume anhydrous ethanol (200 proof) (commonly referred to as the "gasohol waiver").
  • Methanol: Blends of methanol and gasoline-grade tertiary butyl alcohol (GTBA) such that the total oxygen content does not exceed 3.5 percent by weight and the ratio of methanol to GTBA is less than or equal to 1. It is also specified that this blended fuel must meet ASTM volatility specifications (commonly referred to as the "ARCO" waiver).
    Blends of up to 5.0 percent by volume methanol with a minimum of 2.5 percent by volume cosolvent alcohols having a carbon number of 4 or less (i.e., ethanol, propanol, butanol, and/or GTBA). The total oxygen must not exceed 3.7 percent by weight, and the blend must meet ASTM volatility specifications as well as phase separation and alcohol purity specifications (commonly referred to as the "DuPont" waiver).
  • MTBE (Methyl tertiary butyl ether): Blends up to 15.0 percent by volume MTBE which must meet the ASTM D4814 specifications. Blenders must take precautions that the blends are not used as base gasolines for other oxygenated blends (commonly referred to as the "Sun" waiver).
  • Percent Utilization Represents the utilization of all crude oil distillation units. The rate is calculated by dividing gross inputs to these units by the operating/operable refining capacity of the unit.
    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.
    Refinery An installation that manufactures finished petroleum products from crude oil, unfinished oils, natural gas liquids, other hydrocarbons, and oxygenates.
    Reformulated Blendstock for Oxgenate Blending (RBOB) Motor gasoline blending components intended for blending with oxygenates to produce finished reformulated motor gasoline.

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


  • Energy Information Administration, Form EIA-800, "Weekly Refinery Report".
  • Operable Capacity and Percent Utilization are based on data published in the most recent month of Refinery Utilization and Capacity.
  • EIA Forms & Instructions .
  • Explanatory Notes and Detailed Methods Report .

  •   Explanatory Notes

  • Operable capacity is based on the latest reported monthly data.
  • Percent Utilization is calculated as gross inputs divided by the latest reported monthly operable capacity (using unrounded numbers).