Coal is formed when dead plant matter submerged in swamp environments is subjected to the geological forces of heat and pressure over hundreds of millions of years. Over time, the plant matter transforms from moist, low-carbon peat, to coal, an energy- and carbon-dense black or brownish-black sedimentary rock.

Coal is formed when dead plant matter decays into peat and is converted into coal by the heat and pressure of deep burial over millions of years. Coal is primarily used as a fuel.

There are four stages in coal formation: peat, lignite, bituminous and anthracite. The stage depends upon the conditions to which the plant remains are subjected after they were buried – the greater the pressure and heat, the higher the rank of coal.

(Think of peat bogs, swamps and the muck on the bottom of rivers!) If peat becomes buried way underground, it slowly undergoes a chemical processes that turns it into hydrocarbons, which is what coal and oil are made of.

There are four stages in coal formation: peat, lignite, bituminous, and anthracite.

Hydroponics is the use of nutrient containing water instead of soil in the growth of plant life. A third phase in this coal development is bituminous (soft coal) which is one of the two stages used as a fuel in generating electrical power. The fourth and final phase results in the formation of anthracite (hard coal).

Coal is classified into four main types, or ranks: anthracite, bituminous, subbituminous, and lignite. The ranking depends on the types and amounts of carbon the coal contains and on the amount of heat energy the coal can produce.

There are significant environmental impacts associated with coal mining and use. It could require the removal of massive amounts of top soil, leading to erosion, loss of habitat and pollution. Coal mining causes acid mine drainage, which causes heavy metals to dissolve and seep into ground and surface water.

Several principal emissions result from coal combustion: Sulfur dioxide (SO2), which contributes to acid rain and respiratory illnesses. Nitrogen oxides (NOx), which contribute to smog and respiratory illnesses. Particulates, which contribute to smog, haze, and respiratory illnesses and lung disease.

The burning of fossil fuels releases greenhouse gases into the atmosphere, increasing levels of CO2 and other gasses, trapping heat, and contributing to global climate change. Coal-fired power plants release more greenhouse gases per unit of energy produced than any other electricity source (1).

Based on U.S. coal production in 2019, of about 0.706 billion short tons, the recoverable coal reserves would last about 357 years, and recoverable reserves at producing mines would last about 20 years. The actual number of years that those reserves will last depends on changes in production and reserves estimates.

The Pros of Coal Energy

• The availability of coal makes it very affordable.
• The energy infrastructure supports coal.
• The cost of coal is quite cheap.
• There is no lag time with coal energy.
• Clean coal technologies help to limit the emissions that are released.
• It can be converted into different forms of fuel.

Coal contains sulfur and other elements, including dangerous metals such as mercury, lead, and arsenic, that escape into the air when coal is burned. Burning coal also produces particulates that increase air pollution and health dangers. Burning coal emits large amounts of carbon dioxide into the atmosphere.