Approximately 6, 000 cubic feet of natural gas is considered equivalent to one barrel of oil.

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It is convenient to account for both oil and gas in terms of the energy equivalent of a barrel of oil, although actual North Sea oil production has fallen from just above 3 million bpd in1979 to just over one million bpd now.

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Meanwhile, the energy for everything else--offices, factories, homes and data centers is 85% supplied without oil, and most of it is delivered as kilowatt-hours. (Only a vanishingly 2% of electricity is generated by oil.) Once you connect automobiles to the electric grid, you access a trillion-barrel-of-oil-equivalent energy infrastructure almost entirely fueled by domestic sources: coal, uranium, natural gas and hydro dams.

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This, roughly (assuming that 6, 000 cubic feet of natural gas has an energy equivalence of one barrel of oil) amounts to an equivalent of 300 million barrels or 41 million tonnes of oil.

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The fuel pellets typically contain around 10 milligrams of fuel, and if all of that were consumed it would release the energy equivalent to that from burning a barrel of oil.

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Even if Gazprom exercises all its options, the Italian oil giant will have purchased the equivalent of 1.5 billion barrels of oil for less than 50 cents a barrel.

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