PROJECTIONS
Both production-decline-rate models and reserve-decline-rate
models can be used to project future coal production rates for
the coal fields of southwestern Virginia, generally with the limitations
illustrated by the projection models derived from the historical
data for Pennsylvania's anthracite deposits. For Virginia, reserve
decline rate projections appear to be more satisfactory than production
decline rate projections (compare fig. 7 with fig. 8). Accordingly,
the projection of coal production from the southwestern coal fields
depends to a large degree on a reasonable estimate of the amount
of coal reserves remaining in these fields.
Figure 7. Coal projection for Virginia based on
current production decline rates. Virginia's coal production
peaked at 46.5 million tons in 1990 and has declined continuously
to 37.6 million tons during the past 5 years, at an average annual
decline rate of about 4.2 percent. Compare with figure 8. This
model projection appears to be too steep, however, considering
the amount of coal remaining in southwestern Virginia as a potential
reserve.
Figure 8. Coal projection for Virginia based on
reserve decline rates. This model is the preferred projection.
Virginia's coal production peaked at 46.5 million
tons in 1990 and has declined continuously to 37.6 million tons
during the past 5 years, at a decline rate of about 4.2 percent.
At this projected rate of decline, Virginia's coal production
would be only about 5 million tons in 2025, and cumulative production
at 2100 would be about 2.6 billion tons. Virginia's decline in
coal production was anticipated by Milici and Campbell (1991,
1992), who predicted that a general decline would begin shortly
after the beginning of the 21st century. Somewhat surprisingly,
the current decline began 10 years earlier than predicted, apparently
as a result of competition from low-cost western coal, long-term
decline of coke production and consumption (EIA, 1995, Table 7.7),
a 20-year overall decline in real prices for bituminous coal and
lignite (EIA, 1995, Table 7.8), and increased mining costs caused
by depletion of thicker, more accessible coal beds. Current production-decline
rates, however, appear to be too high to be used for a long-term
projection model (fig. 7), considering that Virginia's peak coal
production occurred only 5 years ago and that approximately half
of the original reserve appears to remain in the ground. Production
extrapolations based on the current rate of depletion of a 1.7-billion-ton
hypothetical reserve, however, do not decline as sharply as predictions
made from current production decline rates and descend instead
to about 25 million tons annually within 30 years (fig. 8). In
this case, ultimate production would be about 3.8 billion tons
of coal, or almost all of the estimated original reserve in this
field.
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This page is URL: https://pubs.usgs.gov/circular/c1147/projections.html
For more information, please contact Robert C. Milici
Last revised 9-16-97 (Kathie Watson)