                              Explanatory Text

This report from the 1992 Census of Mineral Industries presents data on the
quantity and cost of fuels and electric energy used in mining.  For most
industries, separate quantity and cost figures were provided on purchased
coal, distillate and residual fuel oil, gas, gasoline, and electric energy.
Only cost figures were obtained for other fuels and undistributed fuels.
The cost for other fuels used in the 1992 Census of Mineral Industries
consists of costs for liquefied petroleum gas, coke, wood, and other minor
fuels. Undistributed fuels include the cost of fuels for establishments
that reported a total cost of fuels but failed to report detailed fuels
data. Also included in undistributed fuels are cost estimates for
establishments which were not mailed report forms. Excluded are fuels for
use as feedstocks or raw materials.

Additional data were obtained on the quantity of fuels produced and
consumed at the same establishment for heat or power. Such data were
obtained on coal, crude petroleum, and natural gas used at the producing
establishment for power and heat. For electric energy, quantity figures
were collected for total generated electric energy and electric energy
sold.

In 1992, the U.S. consumption of fuels and electric energy for heat and
power by mining establishments amounted to 1,843 trillion British thermal
units (Btu). This represented a 6 percent decrease from the 1987
consumption of 1,968 trillion Btu. Establishments classified in the oil and
gas extraction industries (major group 13) were the largest consumers of
energy, accounting for 67 percent of the total energy used. Establishments
located in the State of Texas led in energy consumption with 24 percent of
the total energy used in mining in 1992.

Although the hours worked by production, development, and exploration
workers in mining decreased by 7 percent between 1992 and 1987, the
consumption of energy per hour worked remained about the same. In 1992, the
use of energy per hour worked amounted to 2.10 million Btu; whereas, in
1987, it was 2.09 million Btu.

Consumption of purchased fuels and electric energy for heat and power by
mining establishments amounted to 1,193 trillion Btu. This represented
virtually no change over the 1987 consumption when it was 1,192 trillion
Btu. Consumption of nonpurchased fuels for heat and power decreased 16
percent from the 1987 figure of 776 trillion Btu.

The average cost per million Btu of purchased energy consumed in 1992 by
the mining industries was $5.34, a 10 percent increase from the 1987
average cost. Although coal was the lowest cost fuel on a dollar per Btu
basis, it represented only 5 percent of the total purchased energy consumed
by mining industries. Natural gas accounted for 34 percent of the total
purchased energy used, making it the most widely used fuel.  Electric
energy was the most expensive source of energy at $13.84 per million Btu.

In order to provide figures by industry and geographic area on the basis of
a comparable unit of energy used, data on fuels consumed were converted to
British thermal units (Btu). A Btu is the quantity of heat required to
raise the temperature of 1 pound of water by 1 degree Fahrenheit. Btu
factors reflect the energy content of the various fuels with no regard to
efficiency of use. Since some fuel applications are considerably more
efficient than others (none 100 percent efficient), the Btu figures must be
considered as the maximum amount of available energy. The conversion
factors used in computing these Btu are shown in the following table:

                 Conversion to British Thermal Units: 1992

Kind of energy                                     Btu (millions)
*****************************************************************
Electric energy                       1,000 kWh      3.412
Coal                                 short tons     22.250
Crude petroleum                barrels (42 gal)      5.800
Fuel oil:
  Distillate                   barrels (42 gal)      5.825
  Residual                     barrels (42 gal)      6.287
Natural gas and residue gas   MCF (1,000 cu ft)      1.030
Other fuels                              $1,000        210
Gasoline                              1,000 gal        125
Undistributed                            $1,000        341
