How Do We Get Energy from Coal?
When Was Coal First Used?
Coal has been used by man since very ancient times. Probably the first people to use it were the Chinese. There are records to show the Chinese used coal to smelt copper and iron perhaps as far back in time as three thousand years ago.
Coal is mentioned in Proverbs in the Bible. The Greek philosopher Aristotle, who lived from 384 to 322 BC, mentions coal in his writings.
During the period when the Romans occupied Britain, which began about 50 BC, coal was used. We know this because in the ruins of Roman villas in Britain both coal and cinders have been found.
There are records that show that coal was mined in the Dutch province of Limburg in the year 1113. This mine, now known as the Domaniale Mine, is still being used and produces the most coal in the Netherlands!
How Do We Get Energy from Coal?
Extracting energy from coal is a process that taps into the preserved remains of ancient forests and wetland plants, which thrived in the lush, warm climates of our planet's distant past, hundreds of millions of years ago. These primeval jungles were teeming with life, and as this vegetation died, it sank into the oxygen-poor waters of swamps, a condition that thwarted decomposition. Over time, bacteria broke down the organic material, releasing gases and leaving behind a carbon-rich residue destined to become coal.
This transformation process was gradual. As centuries passed, layers of sediment—mud and sand—accumulated atop the decomposed plant matter. The weight of these layers exerted pressure, squeezing out moisture and compacting the material into a dense, pasty substance. Eventually, this substance hardened into coal, through processes that spanned from one to 250 million years ago.
The concept of energy, or the capacity to perform work, is rooted in the fundamental properties of matter. Everything with mass and volume in our universe is composed of matter, which, at its core, consists of atoms bonded by energy. This intimate relationship between matter and energy is dynamic; matter can transform into energy and vice versa, a cycle that underpins the natural and technological phenomena surrounding us.
The sun is the original source of the energy stored in coal. Ancient plants harnessed solar energy for growth, converting carbon dioxide from the atmosphere into organic carbon compounds. Over eons, these compounds were buried and transformed into coal, a dense store of potential energy waiting to be unlocked.
The process of liberating energy from coal involves combustion. When coal is burned, it generates heat, causing atoms and molecules within the coal to vibrate increasingly faster. This agitation can dislodge electrons, releasing energy. The heat from burning coal transforms the potential energy locked within its carbon bonds into kinetic energy—the active energy that fuels our world. This kinetic energy powers the engines and generators that are integral to modern civilization, from electricity generation to industrial processes.
Thus, the energy journey from ancient sunlight to modern power is a remarkable tale of transformation. It encapsulates the deep time of geological processes, the intricacies of atomic and molecular science, and the ingenuity of human engineering. By burning coal, we are, in essence, harnessing a sliver of the primordial sun's energy, stored in the form of ancient plant matter, to drive the complex machinery of our contemporary lives. This interplay of natural history and human technology underscores the profound ways in which the Earth's resources and the laws of physics underpin the energy systems that sustain modern society.
Different Types of Coal
- Peat: The precursor to coal, peat is a soft, organic material consisting of partly decayed plant matter found in wetlands.
- Lignite (Brown Coal): The lowest rank of coal, lignite is soft, brownish-black, and has a high moisture content. It is used mainly for electricity generation.
- Sub-bituminous Coal: Slightly higher in rank than lignite, sub-bituminous coal is characterized by its lower moisture content and higher carbon content. It is also primarily used for electricity generation.
- Bituminous Coal: A higher grade of coal, bituminous coal is black and contains a significant amount of carbon and fewer impurities. It is used for generating electricity, in industrial processes, and in the production of coke for steel manufacturing.
- Anthracite: The highest rank of coal, anthracite is hard, glossy, and black. It contains the highest carbon content and fewest impurities among all coal types. Anthracite is used for heating residential and commercial buildings, in steel production, and as a filter medium.
- Metallurgical Coal (Coking Coal): Although not a separate rank, this type of coal is used to produce coke, a material needed in the steelmaking process. Metallurgical coal must have low sulfur and phosphorus content and is usually a type of bituminous coal.
These types represent the main categories of coal, each with distinct properties and uses in energy production, industrial processes, and manufacturing.
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.
© 2009 Longtail