U.S. Energy Information Administration - EIA - Independent Statistics and Analysis
U.S. Coal Reserves
With Data for 2011 | Release Date: November 20, 2012 | Next Release Date: November 2013
As of January 1, 2012, the demonstrated reserve base (DRB) was estimated to contain 483 billion short tons. In the United States, coal resources are larger than remaining natural gas and oil resources. Annually, EIA reports remaining tons of coal in the DRB, which is comprised of coal resources that have been identified to specified levels of accuracy and may support economic mining under current technologies.
Between 1990 and 1999, EIA obtained updated coal reserves information and data largely through its Coal Reserves Data Base (CRDB) program. That program encouraged State agencies to revise coal resource and reserves estimates in their respective States. These revised coal reserve estimates include improved analyses of coal quality, accessibility, and recoverability in the study areas. EIA used these new data to revise the DRB.
Recovery rates vary greatly between underground and surface mining. The actual proportion of coal resources that can be recovered economically from undisturbed deposits varies from less than 40 percent in some underground mines to more than 90 percent at some surface mines. In some underground mines, by design a portion of the coal is left intact as pillars to protect against surface collapse. Adverse geologic features in a mining area, such as folding, faulting, and inter-layered rock strata, can limit the amount of coal recovered at some underground and surface mines.
Access to some coal is limited. Because of property rights, land use conflicts, and physical and environmental restrictions, EIA has estimated that only about 50 percent of the DRB may be available or accessible for mining.
EIA annually estimates recoverable coal reserves by adjusting the DRB to reflect accessibility and recovery rates in mining. As of January 1, 2012, EIA estimated that the remaining U.S. recoverable coal reserves totaled over 258 billion short tons (a short ton is a unit of weight equal to 2,000 pounds), from a demonstrated reserve base of 483 billion short tons.
Recoverable coal reserves at producing mines represent the quantity of coal that can be recovered (i.e. mined) from existing coal reserves at reporting mines. These reserves essentially reflect the working inventory at producing mines. In 2011, the recoverable reserves at producing mines were 19.2 billion short tons. EIA conducts an annual survey, Form EIA-7A, “Coal Production and Preparation Report,” to gather and report the quantity of recoverable coal reserves at producing mines.
There are four major ranks of coal in the U.S. classification scheme. In the United States, coal rank is classified according to its heating value, its fixed carbon and volatile matter content, and, to some extent, its caking properties during combustion. The coal ranks from highest to lowest in heating value are:
Of the four ranks, bituminous coal accounts for over half (53.1 percent) of the DRB. Bituminous coal is concentrated primarily east of the Mississippi River, with the greatest amounts in Illinois, Kentucky, and West Virginia.
All subbituminous coal (36.5 percent of the DRB) is west of the Mississippi River. Most subbituminous coal is in Montana and Wyoming.
Lignite, the lowest-rank coal, accounts for about 8.8 percent of the DRB. Lignite is found mostly in Montana, Texas, and North Dakota.
Anthracite, the highest-rank coal, makes up only 1.6 percent of the DRB. Anthracite is concentrated almost entirely in northeastern Pennsylvania.
Coal Data Contacts
U.S. Coal Resource Regions
|Table 14. Recoverable Coal Reserves and Average Percentage at Producing Mines by State||XLS|
|Table 15. Recoverable Coal Reserves at Producing Mines, Estimated Recoverable Reserves, and Demonstrated Reserve Base by Mining Method||XLS|
|Table 16. Recoverable Coal Reserves and Average Recovery Percentage at Producing Underground Coal Mines by State and Mining Method||XLS|
|Table 17. Recoverable Coal Reserves and Average Recovery Percentage at Producing U.S. Mines by Mine Production Range and Mine Type||XLS|