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Stocks of crude petroleum held at refineries in the United States at the end of each
month in 1923.
19, 940 19, 194 22, 662 23, 354 24, 791 25,383 27,767 28, 898 28, 528 29, 995 30,153 29, 756 10,274 8, 919 8, 471| 7, 989 6, 720 8, 335 5,814 5,373 4, 225 3, 674 2, 859 3, 503
29, 914 28, 113 31, 133 31, 343 31, 511 31,718 33,581 34, 271 32, 753 33, 669 33, 012 33, 259
• Bureau of Mines.
CONSUMPTION Although petroleum is utilized chiefly in the form of refined products, concerning which summarized statistics are given on page 425, considerable crude oil, especially the heavier grades produced in the California, Gulf coast, and other domestic fields and heavy crude oil imported from Mexico, is consumed as such without topping or refining in any way. Complete data concerning these uses of crude oil, distinct from fuel oil, have not been compiled.
Besides runs to refinery stills, the only available figures of consumption of crude oil as such are those showing consumption in the operation of crude-oil pipe lines and consumption of oil on the producing properties given in the table on page 408. Figures showing indicated deliveries of crude petroleum to domestic consumers, by fields of origin of the oil, are given in the table below. A table showing indicated domestic consumption of crude petroleum, including runs to stills at refineries and the indicated other consumption of crude oil, chiefly for fuel, and including losses, is also given below.
The relation between supply of crude petroleum (production, imports, and stocks) and demand (indicated deliveries to consumers and exports) for a number of years is shown by Figures 18 and 19.
Annual deliveries to domestic consumers plus exports of domestic and foreign crude petroleum were greater than the quantity of domestic petroleum marketed” from 1911 to 1918, except in 1914. They were greater than domestic “petroleum marketed” plus imports in 1916, 1917, and 1918, the result being that in these three years stocks were drawn upon. In 1919 and 1920 deliveries plus exports amounted to slightly less than combined production and imports, and in 1921 and 1922 they were considerably less, resulting in large additions to stocks. In 1923, because of the greatly increased production and in spite of record high consumption, deliveries plus exports were slightly less than domestic production (see fig. 18) and stocks were increased by more than 8242 million barrels, a quantity greater than the total imports of crude oil.
The monthly relation between the new supply (production and imports) and demand from January, 1919, to December, 1923, is illustrated in Figure 18. From October, 1919, to May, 1920, deliveries plus exports exceeded production plus imports. But from
June, 1920, through December, 1923, except only in December, 1922, for a period of 31 months, deliveries plus exports were not only less than production plus imports but for a period of seven months, from May to November, 1923, were less than production.
FIGURE 19.-Supply and demand for crude petroleum contrasted with price of Oklahoma-Kansas gradə
crude petroleum, 1918-1923
Indicated deliveries of crude petroleum to domestic consumers, 1923, by months
• Calculated result due to reclassification of certain stocks by transfer from refinery to tank farm.
Indicated domestic consumption of crude petroleum, 1929, by months
• Reported to U. S. Geological Survey.
The rapidly increasing number of motor vehicles and oil-burning vessels, as shown below, emphasizes the growth of the demand for liquid fuels for those purposes.
Motor-vehicle registration in the United States, 1910 and 1915–1929 •
(All figures represent thousands)
• Commerce Year Book, 1923.
• Partial total due to classification, by some States, of trucks and commercial cars with other motor
• Separate figures not available.
World oil-burning vessels of 500 gross tons and over, June 30, 1914, 1920–1923
(Exclusive of Army, Navy, Admiralty, and other Government vessels)
• American documented seagoing merchant vessels, Dept. Commerce Bur. Navigation.
COMPARATIVE FUEL VALUE OF COAL, PETROLEUM,
AND NATURAL GAS
The comparison of the fuel value of the coal, petroleum, and natural gas produced in the United States, as shown in the following table and in Figure 20, is based on revised estimates of the energy equivalents of the output of coal of all kinds, of petroleum, and of natural gas reported in Mineral Resources of the United States. These estimates have been made by F. G. Tryon for coal and for the coal equivalent of natural gas consumed for the years 1882–1905 and by the writer for natural
gas for the years 1906–1923 and for petroleum.
FIGURE 20.-Energy equivalent of coal, petroleum, and natural gas, 1882-1923 The conversion factors used in compiling the table assume that the weighted average thermal value per short ton of all bituminous coal produced in the United States equals 26,200,000 British thermal units; per short ton of Pennsylvania anthracite, 27,200,000 British thermal units; per barrel of petroleum, 6,000,000 British thermal units; and per cubic foot of natural gas, 1,075 British thermal units.
The table and diagram emphasize the dominating position of coal and the increasing importance in recent years of the hydrocarbons. Of the total energy supplied by mineral fuels in 1923, coal yielded 76 per cent, petroleum 19 per cent, and natural gas 5 per cent, whereas in 1913 coal yielded 88 per cent of the total, petroleum 9 per cent, and gas
cent. The fluctuating coal curve and the relatively smooth curves for petroleum and natural gas reflect the differences attending the production of these commodities. The fluctuations in the production of