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Annual consumption volumes are available through the Natural Gas Navigator for the Total United
States for 1949 forward. The volumes for 1949 forward represent the current sectoral concepts
introduced in 2001 and used throughout the Energy Information Administration. A comprehensive
description of the concepts and changes they imply may be found in the 2001 Annual Energy Review,
Appendix H,
Estimating and Presenting Power Sector Fuel Use in EIA Publications and Analysis.
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Beginning with 1980 data, dry production and consumption volumes include supplemental gas
supplies, and storage volumes include liquefied natural gas (LNG).
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Balancing Item volumes are equal to Total Disposition (net storage changes plus extraction loss plus consumption) minus Total Supply (marketed production plus net interstate movements plus net movements across U.S. borders plus supplemental gas supplies). Annual balancing item includes net intransit deliveries through the United States for natural gas not contained in the monthly net imports figures.
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Supplemental gaseous fuels data are collected only on an annual basis except for the
Dakota Gasification Inc. coal gasification facility which provides data each month.
The ratio of annual supplemental fuels (excluding Dakota Gasification Inc.) to the sum
of dry gas production, net imports, and net withdrawals from storage is calculated.
This ratio is applied to the monthly sum of these three elements. The Dakota
Gasification Inc. monthly value is added to the result to produce the monthly
supplemental fuels estimate.
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Net storage withdrawals through 2005 include both underground and liquefied storage.
Later data include underground storage only.
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Consumption consists of pipeline fuel use, lease and plant fuel use, vehicle
fuel, and deliveries to consuming sectors.
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Totals may not equal sum of components because of independent rounding.
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| Storage |
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All monthly data concerning underground storage are published from the Form EIA-191M, "Monthly Underground Gas Storage Report."
A new Form EIA-191 became effective in January 1994. Injection and withdrawal data are from the Form EIA-191M
survey.
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The final monthly and annual storage and withdrawal data include both
underground and liquefied natural gas (LNG) storage. Annual data on LNG additions and
withdrawals are taken from Form EIA-191M.
Monthly data are estimated by computing the ratio of each month's underground storage
additions and withdrawals to annual underground storage additions and withdrawals and
applying it to annual LNG data.
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There are three principal types of underground storage facilities in operation in the
United States today: salt caverns (caverns hollowed out in salt "bed" or "dome" formations),
depleted fields (depleted reservoirs in oil and/or gas fields), and aquifer reservoirs
(water-only reservoirs conditioned to hold natural gas). A storage facility's daily
deliverability or withdrawal capability is the amount of gas that can be withdrawn from
it in a 24-hour period. Salt cavern storage facilities generally have high deliverability
because all of the working gas in a given facility can be withdrawn in a relatively short
period of time. (A typical salt cavern cycle is 10 days to deplete working gas, and 20
days to refill working gas.) By contrast, depleted field and aquifer reservoirs are
designed and operated to withdraw all working gas over the course of an entire heating
season (about 150 days). Further, while both traditional and salt cavern facilities can
be switched from withdrawal to injection operations during the heating season, this is
usually more quickly and easily done in salt cavern facilities, reflecting their greater
operational flexibility.
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| Imports and Exports |
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EIA reduced the reported volume of gas imported by pipeline from Canada by the amount of natural gas liquids removed from the saturated natural gas carried by Alliance Pipeline. Alliance moves saturated natural gas from the border to a processing plant in Illinois. After the adjustment, volumes of imported natural gas on this pipeline are on the same physical basis as other reported volumes of pipeline imports.
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Prices for LNG imports are reported as “landed,” received at the
terminal, or “tailgate,” after regasification at the terminal. Generally
the reporting of LNG import prices varies by point of entry, and the
average prices are calculated from a combination of both types of prices.
The price of LNG exports to Japan is the “landed” price, defined as received
at the terminal in Japan.
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Annual and monthly data are published from the Office of Fossil Energy,
U.S. Department of Energy, Natural Gas Imports and Exports.
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Totals may not equal sum of components due to independent rounding.
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LNG prices are a volume-weighted average of the prices reported by cargo. See the LNG Monthly from the Office of Fossil Energy, U.S. Department of Energy, for more information on what is included in the individual LNG prices. Beginning in 2019, LNG export prices applying to fewer than three cargos are withheld in accordance with a policy change with the Office of Fossil Energy.
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Definitions