In 1896, a man named Svante Arrhenius was the first person to suggest that burning fossil fuels for energy could result in changes to the climate. Arrhenius worked with another scientist, Thomas Chamberlin, to model the effects of human activities on the atmosphere. They concluded that if the atmospheric carbon dioxide concentration doubled, the Earth's temperature would rise by 5ºC.
The research of Arrhenius and Chamberlin was forgotten for decades. It wasn't until the 1980s – almost a century after Arrhenius – that people started to take climate change seriously.
But why didn't 1980s governments demand that all fossil fuel power stations be shut down? It's a little more complicated than that. First, let's look at fossil fuels examples, their advantages and disadvantages, and their effects on the environment.
The Definition of Fossil Fuels
Fossil fuels are made from ancient animals and plants. Their remains were buried underground, subject to heat and pressure when they died. As the temperature rose, the fossil molecules broke apart.
At this stage, transitional materials are produced, such as peat and kerogen. These transitional materials can be used as fuel sources but don't store as much energy as fossil fuels.
After millions of years underground, animals and plants decompose into fossil fuels. Humans can extract these through mining and drilling.
Fossil fuels are mixtures made of fossilised animal and plant remains from millions of years ago.
Humans burn fossil fuels to produce energy. This energy can be used for transportation, electricity, powering machinery, and much more.
Examples of Fossil Fuels
Fossil fuels is an umbrella term used to describe non-renewable energy sources. There are three types of fossil fuels: coal, oil and natural gas. From these, secondary products can be made, such as coal products (like coke, coal tar etc.), petroleum, crude oil and other non-renewable wastes.
Coal
Coal is a carbon-based black rock. It is typically found in sedimentary rock deposits where rock and fossilised remains have piled up in layers. Coal is burnt to release energy.
Fig. 1: Coal engines were used to power trains before diesel and electricity, unsplash.com
Oil
Oil is found initially as a solid material between layers of soft sedimentary rock. To produce fuels, the solid material is heated to produce crude oil – a thick, tarry mixture of many different compounds. Once extracted and liquified, crude oil can be separated into different fuel types through fractional distillation.
Learn more about Crude Oil by checking out our article!
Crude oil is heated in a distillation tower. This tower is hot at the bottom and cooler at the top. Condensation trays are set at different heights (and thus, temperatures) in the tower.
The compounds in crude oil all have different boiling point temperatures. When the oil is heated, the various compounds condense at varying heights in the tower, collecting as liquids in the trays.
Natural Gas
Natural gas is an odourless, colourless, flammable gas. It is primarily made up of methane (CH4). Typically, natural gas is found in pockets above oil deposits or between sedimentary rock layers.
Natural gas is burnt to release energy.
Advantages and Disadvantages of Fossil Fuels
Fossil fuels might conjure up images of industrial chimneys vomiting out smoke, pollution, and greenhouse gases. That's true – to an extent! Fossil fuels are responsible for almost 3/4 of carbon emissions from human activities. But there's more to them than meets the eye.
Advantages
Fossil fuels are used around the globe. Approximately 81% of the world's energy comes from burning fossil fuels. This energy supports industry, transport, and hospitals and provides electricity in our homes. If it weren't for fossil fuels, our lives would be very different today. The advantages of fossil fuels are:
- Easy to Store and Transport
Pipelines and tankers transport fossil fuels all around the world. Fossil fuels are a physical energy source, allowing them to be stored until needed.
The Druzhba pipeline carries oil 2500 miles from southeast Russia to Germany. It can carry up to 1.2 million barrels of oil per day.
- Well-developed Infrastructure
Humans have been burning fossil fuels for hundreds of years. As a result, the infrastructure system is highly efficient and often cheap.
Fossil fuels have a high energy density. This means that when burned, these fuels produce lots of energy.
Natural gas is the most energy-dense fossil fuel, producing 55 MJ per kilogram burned.
Energy density is the amount of energy stored in a system or material.
Energy from fossil fuels is consistent and reliable. Unlike some renewable resources (especially wind turbines and solar panels), it does not depend on environmental or weather conditions.
Disadvantages
Despite their wide usage, fossil fuels are not a perfect source of energy. They come with their drawbacks, such as they are:
Fossil fuels are considered non-renewable because they take millions of years to form. Humans are using fossil fuels unsustainably – at a much faster rate than they are being replenished.
We could run out of fossil fuels if the current rate is maintained.
The fossil fuel industry has experienced many accidents, such as leaking pipelines, damaged drilling platforms and oil spills.
In 2010, an explosion on the Deepwater Horizon rig killed eleven people and caused 210 million gallons of oil to spill into the Gulf of Mexico. Over a thousand miles of coastline were polluted, killing an estimated 800,000 birds. The oil spill cost BP over $65 billion.
- Cause Environmental Problems
Burning fossil fuels damages the environment by producing greenhouse gases, releasing pollutants and causing ocean acidification, which all contribute to climate change.
There's more information about this in the next section.
Effects of Fossil Fuels on the Environment
The main problem with fossil fuels is the negative effect they have on the environment.
Greenhouse Gases
When fossil fuels are burnt, they produce large quantities of carbon dioxide. This acts as a greenhouse gas.
Greenhouse gases trap heat in the Earth's atmosphere. A natural greenhouse effect supports life on Earth, but carbon emissions have intensified this.
Excess greenhouse gases in the atmosphere lead to global warming and climate change.
Pollution
Burning fossil fuels emits pollutants. Power plants that use coal are notorious for generating pollution – including mercury, sulphur dioxide and soot.
As a result, coal is considered the most harmful fossil fuel.
Vehicles powered by fossil fuels pollute the atmosphere with carbon monoxide and nitrogen oxide. This produces smog during certain weather conditions, and repeated exposure can lead to respiratory illnesses.
Fig. 2: Areas near power stations experience poor air quality, unsplash.com
Ocean Acidification
Carbon dioxide is slightly acidic. When excess carbon dioxide is emitted into the atmosphere by burning fossil fuels, some of it gets absorbed by the ocean. Since the start of the Industrial Revolution, the oceans have become 30% more acidic.
The amount of calcium carbonate – a substance used by marine organisms to form shells – decreases in acidic conditions.
This could affect the whole ocean food web.
If scientists know how bad fossil fuels are for the environment, why haven't they stopped using them altogether?
- Fossil fuel companies are often rich and politically powerful
- It's difficult to make policy changes
- The convenience of existing infrastructure
- Other energy sources are not perfect solutions
Fossil Fuels vs Renewable Energy
Due to fossil fuels' negative environmental effects, scientists are looking for green energy alternatives.
Renewable energy comes from natural resources that replenish themselves – i.e. they will never run out.
The various types of renewable energy include:
Solar energy
Geothermal energy
Wind energy
Hydropower
Tidal power
Biofuels
To learn more about these renewable energies check out our article on Renewable and Non-Renewable Resources!
The UK has more offshore wind turbines than any other country. Unsplash
| Pros of Renewable Energy | Cons of Renewable Energy |
- Reduced carbon emissions
- No pollutants
- Sustainable
- Cheap energy
| - Variability in supply
- Can be expensive to install
- Construction can damage natural habitats
|
Table 1: Main advantages and disadvantages of renewable energy.
No form of energy generation is without its limitations or downsides. However, renewable energy resources must provide power without contributing to climate change.
Fossil Fuels - Key takeaways
Fossil fuels are made from decomposed animal and plant remains. They take millions of years to form.
Humans burn fossil fuels to provide 81% of the world's energy.
The three types of fossil fuels are coal, oil and natural gas.
Fossil fuels have some advantages, but their negative effects on the environment outweigh these. Burning fossil fuels can cause climate change, pollution, and ocean acidification.
Switching from fossil fuels to renewable energy resources is necessary to provide power without contributing to climate change.
References
- Andrew Turgeon, Petroleum, National Geographic, 2022
- The Editors of Encyclopedia Britannica, Greenhouse Effect, Britannica, 2020
- Ethan Boechler, Energy density, Energy Education University of Calgary, 2021
- Evan Nicoles, Fossil Fuels Pros and Cons, SolarReviews, 2022
- Foreign Policy, The List: The Top Five Global Choke Points, 2006
- Geothermal Rising, Pros and Cons of Renewable Energy Sources, 2022
- Ideal Response, The Top 10 Biggest Oil Spills in History, 2019
- Melissa Denchak, Fossil Fuels: The Dirty Facts, NRDC, 2022
- METGroup, Pros and cons of fossil fuels & why fossil fuels can be good?, 2020
- National Geographic Society, Fossil Fuels, National Geographic, 2022
- Petra Cahill, What the U.S. can learn from the U.K. about wind power, NBC News, 2021
- S. M. Enzler, History of the greenhouse effect and global warming, Lenntech, 2022
- Samantha Gross, Why are fossil fuels so hard to quit?, Brookings, 2020
- Smithsonian Ocean, What are Fossil Fuels?, 2022
- United Nations, What is renewable energy?, 2022
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