The majority of the World's energy comes from material formed hundreds of millions of years ago: Fossil fuels. Fossil fuels are mined via underground and surface methods and accounts for approximately 80% of the global energy supply.
What are Fossil Fuels?
Fossil fuels are decomposing plants and other organisms that were buried millions of years ago between layers of rock and sediment. Depending on the type of organic matter, temperature, a
Fossil fuels are not renewable. They are exhaustible and one day their supply will run out. Natural gas, coal, and oil are all considered fossils fuels.
They not only provide electricity, heat, and transportation but also supply the processes that go into making products like plastic and steel.
Types of Fossil Fuels
There are three main fossil fuels used today:
- Natural Gas
Mined from below the surface, coal is instantly recognizable as dark brown and black lumps of sedimentary rock. It differs in textures, some pieces are hard and robust whilst others are soft and crumbly.
Coal that we burn today has laid undisturbed for 300 to 360 million years, during the time known as the Carboniferous Period.
It is formed from algae and other debris in swamp forests that have settled beneath ever-deepening layers of mud.
Coal is responsible for a third of all of the world's energy.
There are four types of coal, categorized by their carbon content
They are ranked from highest to lowest carbon content. Coal with the highest carbon content burns the cleanest and best. As you move down the rankings heating capabilities reduce as the fuel becomes dirtier and its moisture content increases.
This hard coal of compact chunks has a metallic sheen to it.
- Least plentiful, accounting for only 2% of all American coal reserves
- Highest carbon content
- Fewest impurities
- Highest energy density
This is a lump of soft, dense coal that from a distance appears shiny and smooth, however, upon closer inspection, it is made up of multiple bright and dull bands.
- Most abundant
- Most used in US electricity generation as it is less expensive to mine than anthracite
- Contains 65 - 85% carbon
- High heating value
- Burns with a characteristically bright, smoky flame
Otherwise known as black lignite. Sub-bituminous coal has similar characteristics to bituminous coal.
- Geologically young coal at just 251 million years old
- Relatively low carbon content of 40 – 60%
- When combined with bituminous gold, it makes up almost 90% of all coal consumed
- Suited to electricity generation, space heating, transportation, and storage
- Very low sulfur content
Known as soft brown, for its density and coloring. It is the lowest ranking of all coals due to its lack of heat content.
- Made from naturally compressed peat
- Contains 20 – 35% carbon
- Used almost exclusively for steam electric power generation
- Of all coal types, it is the most harmful to health
Crude oil is extracted by onshore and offshore wells. It is a mostly black liquid composed mainly of carbon and hydrogen.
Its viscosity and color depend upon its chemical composition.
Oil was formed when plankton, algae, and other matter sunk to the bottom of ancient seas where it was continually buried. This occurred during the Mesozoic period between 252 and 66 million years ago.
Crude oil is refined to form a selection of petroleum-based products including gasoline, heating oil, and diesel. The U.S. is one of the top oil-producing countries in the world, along with Saudi Arabia and Russia. Between the 3, almost 40% of the world's oil demand is met.
Oil demand continues to rise due to its widespread use in the plastics industry. Most plastic is made using petrochemicals, usually derived from oil and gas.
Just like other fossil fuels, natural gas is formed from millions of year old deposits of decaying plant and organic matter.
Natural gas is odorless, which might sound difficult to believe when it consists primarily of methane.
In the U.S. Both gas and oil production has increased dramatically in the last 20 years, due to major advances in drilling techniques – fracking.
This is the term for hydraulic fracturing, and when this method is combined with horizontal drilling techniques, sources that were previously too deep and too expensive to reach become available.
America is now the world leader in natural gas production, and it has even surpassed coal as the most used fuel in electricity production.
Fossil Fuels Pros and Cons
This list will be broken down based on the pros and cons associated with fossil fuels:
- Natural Gas
Pros of Coal
The following are the advantages associated with using coal:
It's Available in Abundance
Not only is coal always available, but it is also stockpiled ready for immediate use. There is an estimated reserve of one trillion tons of coal. However the current reserves may not last until the end of the century. With that said, coal is a finite resource and is non-renewable on a human timescale.
For homeowners, the cost of a ton of coal is affordable and provides weeks worth of heat.
Also, as it is mass-produced at a relatively low cost, those saving are passed on to the fuel that it produces.
It is accessible to virtually anyone as the cost equates to a few cents per kilowatt-hour.
Industry is Designed Around it
For more than 200 years homes and businesses have used coal to keep warm, steam locomotives have relied on it to move. Infrastructure has been designed around the knowledge that coal is a cheap, reliable, and efficient source of energy.
Renewable energy such as wind and solar power are both reliant on climate and sunlight. If they aren't favorable then energy production draws to a halt, and expensive battery power has to be used to access any stored resources.
Coal is physical resource and is readily available when it's needed. It can be mined, stored, and transported at times of high demand.
Along with soaring demand for coal comes new technology designed to massively reduce emissions. As coal combusts it emits gases that cause damage to the environment.
These technologies aid in the capture of the carbon and store it safely in order to limit potential damage.
Other Clean-Burning Methods
Coal can be converted to a liquid or gas. In such states, it burns inherently cleaner in its solid form, without losing any of its heating capacity.
Cons of Coal
There are also disadvantages of Coal to consider:
The Cost to Human Life
There have been multiple mining accidents over the years where countless miners have lost their lives.
Miners also suffer from lung and respiratory disease from the constant inhalation of coal dust. Among the mining community, it is known as Black Lung Disease.
Burning coal creates over 40% of the world's carbon dioxide emissions and 72% of total Greenhouse Gases.
This accounts for rising global temperatures and has a detrimental effect on climate change.
Destruction of Habitats
Areas of mining are synonymous with the destruction of ecology and wildlife habitats. The removal of trees destroys the homes and feeding sources for many animals.
The groundwater within the region is likely to become polluted and underground mines carry a high risk of fire.
Once an area has been mined to capacity, there may be environmental toxins such as arsenic, sulfur dioxide, and mercury left behind.
Employing clean coal technologies might be environmentally friendly but it is incredibly expensive to make the transition. An expense that will get passed on to the consumer. For example, changing coal-fired plants to use clean coal energy might see a 75% increase in the cost of fuel produced.
Although coal is available in abundance, it is a fossil fuel, and will, at some point, run out.
Coal-fired power plants emit low levels of radiation, but higher than any other fuel type. Sadly they are linked to higher rates of lung cancer and asthma in local areas.
Pros of Oil
The following are the advantages of using oil:
Centuries of innovation have enabled cheap energy production from oil consumption.
Our infrastructure is based on it; underground networks exist to easily transport liquid oil through pipelines covering large distances to isolated, rural areas.
It is an accessible fuel for everyone, almost every country in the world has access to an oil source.
It is comparatively cheaper than any non-renewable fuel, unlike wind and solar power. Oil is easy to store safely.
Oil is a substantial fuel, so much so that only a small amount is required for a large energy output.
For this reason, it is the main choice to power industrial machinery, planes, factories, and some vehicles.
It is essential for many industries including agriculture, automotive, clothing, and medicine.
Easy to Produce and Refine
Manufacturing oil is a simple process that has to adhere to strict industry regulations.
From drilling oil at source through to the refinement process is a meticulous systematic production line.
Aids Economic Growth
The oil industry supplements the economic growth of many countries.
Oil is relied upon to keep the machines running that make the most efficient machines easy to build.
This routine efficiency saves time, energy, and money.
The oil industry is responsible for mass employment down the food chain.
Cons of Oil
These are the cons associated with crude oil:
Despite its many positive attributes, oil is an exhaustible resource and the supply will run out at some point.
Nearly half of US carbon emissions and a third of global emissions are a result of oil burning, being drilled, and transported.
Oil combustion leads to methane and carbon dioxide being released into the atmosphere.
Not only are they major pollutants, but they also trap heat, making oil a major contributor to global warming.
The Threat to Wildlife and Mankind
Underground pipework is not infallible and prone to leakage. This results in pollution and the possible threat of explosion. Not only is this harmful to wildlife and habitats, but it also poses a huge risk to humans.
Oil Drill Disasters
Major incidents are not unheard of within the oil industry. The name Exxon Valdez is synonymous with the oil spill and the resultant catastrophic effect the oil slick had on the wildlife in 1989. Then there was the Deepwater Horizon disaster, the largest explosion, and oil spill known to man. Sadly, 11 oil workers lost their lives.
Emissions created by and leaking from oil refineries create many issues. They are rich in pollutants such as sulfur dioxide which can create a health hazard to those in close populations.
When these pollutants combine with atmospheric water, acids are formed. Acid rain causes great environmental harm, particularly to forests and lakes. This creates many ecological knock-on effects as both are natural habitats.
Pros of Natural Gas
These are the advantages associated with natural gas:
Of all fossil fuels, natural gas burns the cleanest. It emits 45% less carbon dioxide than coal and 30% less than oil.
Gas has a less adverse environmental impact.
Although it is a finite resource, natural gas is available in abundance. There are more than 6879 trillion cubic feet available in the US.
It is thought that natural gas use will successfully replace coal and oil within 2 or 3 decades.
Safer Storage and Transportation
As the most efficient source of generating electricity and heating, it needs to be safe for domestic use. In its liquid form, it is safe to store above and below ground.
Transporting natural gas is done via the existing network of underground pipelines.
Above ground, it is common to use large ships and tankers to transfer gas around the country and beyond.
Globally, most engines require gas to run, as do many vehicles. As gas is so energy-efficient, they are cheaper to run.
Natural gas is also used for cooking and heating because it is an affordable energy source and releases less damaging emissions.
Oil-Producing Countries Can't Hold Others Ransom
As gas is a reliable alternative to power vehicles and it can be used to generate electricity, gas makes countries almost self-sufficient.
It reduces their dependency on large oil-producing countries who can set their prices as they see fit.
Cons of Natural Gas
These are the disadvantages associated with Natural Gas:
Natural gas is a fossil fuel and, as such, will release damaging emissions to some extent.
Although natural gas is available in plentiful supply, it is a finite resource. There will come a time when availability runs out, albeit a long way off.
Adds to the Greenhouse Effect
No matter in which circumstances gas is heated, whether it be for generating electricity, in the engine of a vehicle, cooking, or heating a home, harmful gases are released.
Carbon monoxide, carbon dioxide, and nitrogen oxides released into the atmosphere trap heat from the sun and contribute to global warming by raising the atmospheric temperature.
It is Highly Flammable
Natural gas is colorless and tasteless. You might be surprised to learn that it is also odorless. An odorant is added during refinement to aid detection.
Without it, gas leaks might go unnoticed; gas explosions can be catastrophic and cause a huge threat to life as well as the financial impact.
Just like drilling for oil, hydraulic fracturing, fracking, is employed which cracks the seam of some rocks for extraction.
The highly pressurized liquid can contaminate drinking water in the region.
Also, as the rock has been weakened, earthquakes are more prevalent.
Although it is easy to transfer natural gas from one place to another, the cost of the infrastructure is huge.
Due to its volatility, gas has to be moved in secure pipework and vehicles.
When objectively looking at each fossil fuels, it's not hard to see why they are used across the globe. The current infrastructure is setup to use them and they're efficient means of providing energy.
However, all fossil fuels are finite resources and typically have negative environmental impact due to how they're sourced and used.