Most of our coal is used to generate electricity
Over 92% of the coal consumed in the United States is used for generating electricity. The United States has around 1,400 coal-fired electricity generating units in operation at almost 600 plants across the country. Together, these power plants generate almost 40% of the total net electricity produced in the United States and consume more than 800 million short tons of coal.
Coal is a relatively inexpensive fuel
Although some natural gas plants are more efficient than coal plants at generating electricity, in the past the fuel cost of generating one kilowatt hour of electricity from natural gas had typically been higher than that of coal.
The Mine Safety and Health Administration (MSHA) recently updated its Mine Safety and Health at a Glance statistics compilation to reflect preliminary 2012 data. The latest figures show continued progress in mine safety, as the total injury rate for 2012 fell to a record low of 2.56 injuries / 200,000 hours worked while the fatality rate also hit a record low at 0.0107. Mine fatalities dropped from 37 in 2011, to 35 in 2012. The number of miners employed increased by 6,462 to 387,671 in 2012—reflecting strong demand for metal-nonmetal mining products last year.
- Total demand for U.S. coal reached 1.05 billion tons.
- Nearly half of U.S. electricity is generated from coal.
- Each person in the U.S. uses 3.4 tons of coal annually.
U.S. Coal Production
- Nearly 30 percent of U.S. mines are owned by public companies. Public companies produce approximately 75 percent of U.S. coal.
- The U.S. produces about 1 billion tons of coal annually.
- Approximately two-thirds of today’s coal production results from surface mining, rather than underground mining.
- The U.S. has the largest amount of recoverable coal reserves at nearly 261 billion tons of recoverable coal reserves, according to the Energy Information Administration.
- That’s a 235-year supply at current rates of use.
- Coal is found in 38 states, under 458,600 square miles-or about 13 percent of the nation’s land area.
U.S. Coal Mining Employment
- U.S. coal mining directly employs nearly 90,000 people.
- For each coal mining job, an additional 3.5 jobs are created elsewhere in the economy.
- The National Mining Association estimates 50,000 new employees will be needed in coal mining over the next 10 years to meet increasing demand and to replace retiring workers.
U.S. Coal and the Environment
- Power plants being built today emit 90 percent less pollutants (SO2, NOx, Particulates, mercury) than the plants they replace from the 1970s, according the National Energy Technology Laboratory.
- Regulated emissions from coal-based electricity generation have decreased overall by over 50 percent since the 1970s while coal use has tripled, according to government statistics.
Four Basic Varieties of Coal
Bituminous or “soft” coal formed when greater pressure was applied to subbituminous coal. This is the type most commonly used for electric power generation in the U.S. It has a higher heating value than either lignite or subbituminous, but less than that of anthracite. Bituminous coal averages 24 million BTU per ton.
Sometimes also called “hard coal,” anthracite was formed from bituminous coal when great pressures developed in folded rock strata during the creation of mountain ranges. Anthracite has the highest energy content of all coals and is used for space heating and generating electricity. Anthracite averages 25 million BTU per ton.
Subbituminous coal formed from lignite when it came under higher pressure. This coal is a combustible mineral formed from the remains of trees, ferns and other plants that existed and died during the time of the dinosaurs. A dull black coal with a higher heating value than lignite that is used primarily for generating electricity and for space heating. Subbituminous coal averages 18 million BTU per ton.
Increased pressures and heat from overlying strata caused buried peat to dry and harden into lignite. Lignite is a brownish-black coal with generally high moisture and ash content and lower heating value. However, it is an important form of energy for generating electricity, particularly in the American Southwest. Lignite averages 14 million BTU per ton.