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Fossil Fuels: An Inconvenient Future


AL has a Bachelor of Science in Natural Resources and Environmental Studies.


Fossil fuels—coal, oil, and natural gas—are currently the world's primary energy source. Naturally formed from organic material over the course of millions of years, These non-renewable resources have fueled the global economy for centuries. However, they are finite resources, and a future without them is a very real prospect.

The Strength of Fossil Fuels

Today, fossil fuels are still the world's number one go-to energy source, a position held since the industrial revolution of the 19th century, which was fueled by coal. The 20th century is sometimes referred to as the petroleum age and natural gas was touted as the future of energy. In the 21st century, these energy sources still reign supreme. Their dominance of the energy sector for centuries despite a well-documented history of pollution is a clear indication of the strength and resilience that lies within these fossil fuels, and they are showing little signs of slowing down in the near future.


A Statista report from 2018 showed the world's primary energy sources consisted of a majority share of the global energy sector:

  • Petroleum 34%
  • Coal 27%
  • Natural gas 24%

Some factors have, however, sustained this continuous dependency on non-renewable and environmentally hazardous fossil fuels for centuries.


The strength of coal as a fossil fuel lies in its wide geographical distribution. The large sedimentary basins containing rocks that accommodate coal are found on all seven continents. In addition to its wide distribution, coal is also a cost-competitive fuel that is able to supply a stable and secure source of energy.

Worldwide, coal-generated electricity accounted for 38.5% of all electricity generated. (Statista, 2020). The usage of coal as an energy source is very significant in developing countries due to its cost-competitiveness. Expanding economies like China and India also use coal as a cheaper energy source to fuel their economies. In 2016, China accounted for 51% of all global coal consumption and India at 11%.

The United States Energy Information Administration (EIA) estimated about 13% of total U.S. energy consumption in 2018 was produced by coal. The Trump administration has most recently been working towards reviving the dying coal industry in the US.


Coal is, however, a very dangerous energy source and a heavy air polluting agent, it has been linked to severe environmental and public health impacts. It is known to cause cancer, asthma, heart and lung illnesses. It is also a prominent greenhouse gas contributor linked to acid rains and sporadic weather patterns. It is for these reasons the coal industry is experiencing a slow but steady decline, it is a common source of environmental protests, and coal mining is considered one of the most dangerous occupations.

Despite all these, the coal industry is still very much alive today and still has a higher energy sector contribution compared to cleaner sources of energy.

As of December 31, 2017, EIA estimates of the total world proved recoverable reserves of coal were about 1,114 billion short tons. Using the ratio of reserves to current rates of production, coal is expected to run out in approximately 110 years. These figures are future estimates and may change, but it gives us an idea of the finite nature of a resource like coal.


Petroleum Oil

Petroleum oil, the most popular energy source, sometimes referred to as 'liquid gold'. It is a combination of crude oil and other liquids produced from fossil fuels and refined into petroleum. It is the most widely used energy source, its uses include; powering vehicles, generating electricity and heating buildings. It is also used as a raw material in many household products and goods, most notably plastic materials.

The liquid state of oil is, however, its greatest strength. It is easy to transport and to handle, this is the reason why the transportation industry is predominantly powered by oil. According to an EIA report, petroleum products accounted for about 92% of the total U.S. transportation sector energy use in 2018.

Globally, 95% of transportation is reliant on petroleum products. The demand for oil is dependant on the ever-increasing transport sector. The continuous growth of the transport sector means the future demand for oil will continue to grow, while the demand for oil in other sectors remains stable.


Oil is, however, also a non-renewable fossil fuel like coal; it can be depleted at a rate faster than it can be replenished.

Statista's report of oil showed that we currently consume the equivalent of over 11 billion tonnes of oil from fossil fuels every year. Crude oil reserves are depleted at a rate of more than 4 billion tonnes a year. If this trend continues oil is expected to run out in approximately 53 years.

In addition to the prospect of running out, the hydrocarbon composition of petroleum oil also means its energy combustion byproducts are in the form of carbon emissions which are known pollutants and greenhouse gases. Exposure to petroleum is also toxic for most life on our planet. Oil spills in water are especially detrimental, it changes the composition of water and thereby affects the biodiversity around the affected area. Oil contamination may persist in the affected environment for many years after an oil spill before returning to normalcy.

Replacing petroleum oil with a cleaner alternative is, however, a very difficult task. Not only does it account for 95% of the transport sector fuel, but it also fuels the growth of global economies. An increase or decrease in petroleum prices causes an increase or decrease in the prices of goods and services. The underlined importance of petroleum oil has also been a source of conflict and warfare. The important role petroleum oil plays on the world stage is set to continue into the future, despite the threat of running out.


Natural Gas

Natural gas is considered the most environmentally friendly fossil fuel, occurs naturally and abundantly deep within the Earth from decomposed organic matter. It is stripped down to methane and other gases before being used by consumers.

Methane is the most commonly used natural gas. It is used to generate electricity through gas and steam turbines. It is also used in cooking and heating homes, air conditioning, and other important home activities. Other Natural gas derivatives include; ethane, propane, butane, pentane, and hexane. In addition to household uses, these gases are used in industries as organic solvents, some are used in the production of gasoline and sometimes used as agents in food processing.


Natural gas usage has been increasing worldwide. In 2017, natural gases accounted for 23% of global electricity generation. The United States is the largest consumer of natural gas, the EIA estimated natural gas usage for 2018 at 31% of total U.S. primary energy consumption.

Natural gas like any other fossil fuel is also considered a non-renewable resource. In 2018, the EIA reported an estimated 7,124 trillion cubic feet of global natural gas reserves. If the trend of consumption continues, natural gas is projected to run out in approximately 54 years.

Although natural gas is considered environmentally friendly and non-toxic, exposure to it in a confined space can cause suffocation and death, under extreme conditions, it can cause a fire or an explosion.

Regardless, natural gas is still considered a cleaner and cost-effective fossil fuel energy source and its use is expected to extend well into the immediate future.


Future Outlook of Fossil Fuels

The rough estimates of the number of years that are remaining before we run out of these resources paint a very grim future for energy. Not only do these resources account for the majority share of the energy sector, but they also contribute significantly to the global economy. The transport and energy sectors are heavily reliant on these fossil fuels. Many economies are built, expanded and maintained around these resources. A gradual shift towards cleaner forms of energy means a gradual and expensive restructuring of a lot of sectors. This shift is expensive even for developed countries, shifting their already structured sectors, from one energy resource to another is a mammoth task. For developing countries that are still developing their structures, using renewable energy as a resource is an expensive task that does not adequately address their immediate need for progress now.

it is very clear, fossil fuels are running out, they will not run out today or tomorrow, but they will eventually run out. The increase in the global population means the demand for these fuels will still continue to rise, until the time when we are able to switch to alternative, renewable and cleaner forms of energy.

Current Stock of Fossil Fuels

Non-Renewable ResourceTotal Number of Reserves leftNumber of Years Before Depletion


1.73 trillion barrels


Natural Gas

7,124 trillion cubic feet



1055 billion tonnes



  1. Coal - Energy Explained, U.S. Department of Energy, Energy Information Administration, Independent Statistics & Analysis.2015.
  2. Global Consumption Subsidies for Fossil Fuels by Source 2010-2018, Statista 2018.
  3. Primary Energy: Consumption by Fuel, BP Statistical Review of World Energy 2019.
  4. History of Fossil Fuels, U.S. Department of Energy, Energy Information Administration, Independent Statistics & Analysis.2015.

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.

© 2020 AL


AL (author) from South Equator, East Pacific on February 16, 2020:

As always, Thanx Umesh Chandra Bhatt. I am currently compiling another list of cleaner renewable energy sources.

Umesh Chandra Bhatt from Kharghar, Navi Mumbai, India on February 16, 2020:

Very good compilation and well presented.

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