The Past, Present, and Future of Coal

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Podcast Transcript

Ancient people around the world all made a rather similar discovery. In certain places, they could find a black stone in the ground which could burn. Coal.

For the most part, this combustible black rock took a backseat to wood as a fuel source, but eventually, it replaced wood and was the fuel source that drove the industrial revolution. 

Over time, other energy sources surpassed coal, and now coal appears to be on its way out. 

Learn more about coal, its past, present, and future as a source of energy, on this episode of Everything Everywhere Daily.

I might as well start the beginning by explaining exactly what coal is. 

Coal is a black, sedimentary rock that was formed geologically from dead organic matter. The way it was believed to have been formed was from vast swamp forests which covered most of the Earth during the late Carboniferous period, about 300 to 323 million years ago. 

These swamp forests were, as the name would suggest, large swampy areas with dense tree growth. As the plants died, they fell into the muddy water where they couldn’t oxidize and decay. Eventually, this layer of organic matter built up and was covered by more sediment layers. 

Over time, this layer of organic matter would become peat which in and of itself is a combustible fuel source.

After further compression by more sediment over millions of years, water, methane, and carbon dioxide would be expelled, leaving a denser rock with more carbon. 

Coal is a rock, but it is not a mineral, so there isn’t a single chemical formula for coal. There are different types of coal based on the geological processes which acted on it.

There are four rough grades of coal. 

The lowest grade of coal is Lignite. Lignite is brownish in color and has the lowest amount of carbon and the highest amount of moisture. This is usually used for electrical generation.

The next highest grade is Subbituminous. It is black and has a dull appearance. It is also used for electrical generation.

Above that is bituminous. This is black and shinier with higher carbon content. It can be used for electrical generation, but it is also used for creating heat in steelmaking.

The highest grade of coal is anthracite. This is also known as hard coal. It has the most luster, least impurities, and carbon content of over 85%.  Only 1% of all coal in the world is anthracite.

A geologist by the name of Carl Hilt in the late 19th century established what is known as ??Hilt’s Law, which says that the deeper the coal, the higher its grade. 

Humans knew about coal early on. Where coal seams managed to reach the surface, coal was easily accessible. 

Early humans found coal almost everywhere on Earth. The first recorded use of coal came from northern China about 6,000 years ago. Some of the first uses were as a stone that could be easily carved. 

However, the early Chinese also found out that this stone could burn, and they had lots of it. 

Marco Polo noted coal was used extensively in China during his travels in the 13th century. 

Coal was also used on the island of Britain during the Bronze Age, and it was also exploited during the Roman Era. There is also ample evidence of the Greeks, Aztecs, and other cultures using coal when and where they could find it.

While coal was used, it wasn’t necessarily the preferred fuel source. Mining was more difficult than chopping down trees, so it had limited use. 

The place where coal use really took off was in Britain. 

The coal trade as an industry began around the year 1000, and it was used as a source of heat and for cooking. However, for centuries it still took a backseat to wood. In 1306, after it became obvious that coal was much more polluting, coal was banned by royal decree in London by King Edward I. 

By the late 16th and early 17th centuries, however, Britain was running out of trees. Coal production had to be stepped up, which meant that simple hand-dug pits and coal taken from seawalls where the coal seams were exposed wasn’t going to be enough. 

This meant the creation of coal mines to meet the demand for coal. 

Here I should probably note the difference between coal and wood. The amount of energy contained in wood and coal per unit of mass isn’t that much different. The big difference is that coal is much denser, so it has more energy per unit of volume. 

Coal mining was, and still is, a very dangerous, dirty business. You were literally digging up something flammable, which would often have pockets of methane. On top of that, there was also dust that came from the coal which got into everything, including the lungs of miners. 

One big difference between mining for coal and mining for ore is that you could use most of what came out of a coal mine. If you were mining for gold, silver, or copper, there would usually be a tiny amount of ore and a lot of useless rock. 

If you remember back to my episode on the steam engine, the very first steam engines were designed as pumps to take water out of coal mines. So, the steam engine was invented to facilitate coal mining, but it needed a source of fuel which increased the demand for even more coal.

From 1700 to 1750, British coal production increased by 50%. From 1750 to 1800, it had increased another 100%. 

In the next 50 years, from 1800 to 1850, coal production increased 500%. 

Coal drove the industrial revolution in the 19th century. It fueled the trains, steamships, and factories. Coal mining sprung up all over the world. Germany, Russia, North America, South Africa, Mexico, Australia, India, China, and Japan

Coal also became the preferred fuel source in major cities due to its compact form of energy. Homes had coal-burning fireplaces and stoves. Coal would be delivered to buildings via a coal chute. 

There was another major use for coal that drove the industrial revolution: coke. Coke is coal that has been heated to remove most impurities and to increase its carbon content. Coke is to coal, what charcoal is to wood.

Coke is critical in the creation of iron and steel as it can burn hotter than coal, which is necessary when using blast furnaces to produce cast iron.

The 19th century also saw the rise of coal gasification. Coal gas is the product of heating coal without any air, and it is a byproduct of the creation of coke. The resulting gas is a mixture of methane, carbon monoxide, carbon dioxide, hydrogen gas, and water. 

Coal gas was what was primarily used to light gas street lamps at night, and eventually, it was extended to homes for use in heating and cooking. 

It was primarily the domestic use of coal that made London such a dirty place in the latter half of the 19th century.  What Edward I knew over 500 years earlier hadn’t changed. Coal was dirty. Far more dirty than wood in terms of the quantity and quality of what is emitted during combustion. 

Coal releases ash, nitrous oxide, sulfur dioxide, and heavy metal particles, including trace amounts of radioactive elements. 

These coal emissions, coupled with London’s famous fog, resulted in several severe 19th-century smog episodes. In 1873, a smog lasted three days and killed 700 people. In 1880, an even worse smog event occurred, which killed approximately 1,000 people, and in 1893, another smog event killed 1,000 people. 

Perhaps the worst event was the Great Smog of 1952. For four days, London was brought to a standstill by a coal-induced smog. Initial estimates were that it killed 4,000 people, but later estimates have raised that number to 10-12,000.

The sky was so dark so consistently in several large British cities that they saw a resurgence of rickets, which is caused by a vitamin D deficiency. 

In Manchester, of the 11,000 men who volunteered for the Boer War in 1899, 8,000 were found physically unfit for service. 

The 20th century saw several major developments which affected the use of coal. 

Electrification moved a great deal of coal burning to centralized power stations. It wasn’t necessary to have coal on-site to run steam-powered machinery in most places.  This removed much of the infrastructure surrounding the delivery of coal as now it just had to go to a few places.

While the use of coal shifted to fewer, larger facilities, overall demand for coal didn’t decrease.  Throughout the 20th century, coal remained the cheapest and most abundant source of fuel for power plants. 

The year which saw the largest amount of gross coal used in the world actually occurred in 2013. Today 38% of all the electricity in the world comes from coal-fired electrical plants, with over half of that coming from a single country: China. 

Mining for coal can be done in one of two ways, depending on where the coal is located. If a coal seam goes deep underground, then it requires the use of a mine shaft and underground mining. If the seam is near the surface, then it can usually be extracted via open pit or strip mining. 

Open pit mining is far more cost-effective and safer than underground mining, but it also does more damage to the environment as everything is exposed to the surface. 

The type of mine is dependent on quirks of local geography. In Britain and China, most coal mines were or are deep underground. In the United States and Germany, many coal mines are open air. The largest coal-producing state in the US is Wyoming, which is almost entirely surface mining. It produces more than 3 ½ times more than the second state, which is West Virginia.

The largest vehicle in the world is the Bagger 293 excavator, which is in use at the Hamback Surface Mine in Germany, located between Frankfurt and Cologne. It is over 300 feet tall, 700 feet long, and weighs 14,200 tonnes.

Coal mining in Britain, which at one point was probably the single largest industry in the country, hiring over 1,200,000 people at its peak in 1920, effectually ceased in 2015 with the closure of the last deep coal mine in the country. 

One side effect of underground coal seams is that sometimes they can start on fire. When a coal seam ignites, it can burn for hundred or thousands of years. Most coal seam fires are actually natural occurrences. There is evidence of coal seams burning underground over a million years ago.

Burning Mountain, Australia, located 225 kilometers north of Sydney, is an underground fire that has been burning for over 6,000 years. 

The town of Centralia, Pennsylvania, has all but been abandoned due to an underground coal fire that began in 1962. Since the fire started, the population of the town has gone from 1,500 people down to just five today. It is estimated that the fire might burn for another 250 years.

Today, the biggest trend in coal is trying to eliminate it. As I mentioned before, it is the dirtiest of all fossil fuels by a wide margin. Coal is responsible for 25% of all CO2 emissions worldwide. 

An average coal-fired power plant will release twice as much carbon dioxide as a gas-fired plant to produce the same amount of electricity. Simply moving from coal to gas can have enormous emission benefits. 

That is only taking into consideration CO2. Coal also emits a host of particulate matter that natural gas doesn’t.  Coal is estimated to be the cause of 800,000 premature deaths each year, mostly to do particular matter. The vast majority of these deaths occur in China and India. 

Some steps can be taken, and technologies can be used to reduce coal emissions. Most modern coal-fired power plants will use some combination of these. 

However, a report published in 2021 found that just 5% of coal-fired power plants in the world are responsible for 73% of all emissions from electrical production. 

The world’s worst power plant is located in Be?chatów, (Bel-how-toof) Poland

Most people probably don’t realize how much coal is still used in the world today. Coal isn’t something that the average person experiences or even sees anymore unless you happen to live near a coal-fired power plant. 

Odds are we have probably experienced peak coal. Alternative sources of electrical generation such as gas, wind, solar, and nuclear are far cleaner and safer. In most countries outside of China, the replacement of coal with other sources of power has been underway for years.

Nonetheless, despite its diminished role in the future, coal was the critical fuel source that made the industrial revolution possible. Without coal, it probably never would have happened. 


The executive producer is Darcy Adams.

The associate producers are Thor Thomsen and Peter Bennett.

I have a bunch of boostagrams to read today. 

I received several dozen 1,000 sat boosts from Petar, who has been going through the back catalog on the Fountain Podcast app. In the episode about Stanislav Petrov: The Man Who Saved the World, he simply said, “Thank you Stanislav!” 

…and considering that Stanislav single-handedly prevented an accidental nuclear war from starting, I think that thanks are in order. 

Dave Jones sent me his weekly 12112 sat boost as well as a 2112 sat boost on the episodes about imaginary numbers. He said: 

It’s always good to remember that mathematics is simply an analog (sometimes a really good one) of the real world and not an actual representation. Things like infinites are necessary to satisfy the equations (and do work), but actual infinites can’t exist (Hilbert’s Hotel paradox).

Dave, you have stumbled into the biggest philosophical debate in the history of mathematics. The question of if mathematics is discovered or if it is invented. 

This debate has literally gone on for centuries and has great mathematicians on each side of the issue. I don’t think I’m going to resolve it at the end of a podcast, but it might be worth an episode of its own in the future. 

If you are interested in participating in boostagrams, there are several links I’ve put into the shownotes of this episode that you can read and find out more.