Fossil Fuels: An Overview
Fossil Fuels
0. Introduction
We obtain fossil energy from the combustion of fossil fuels, which were created over millions of years. Therefore, we can say that fossil energy is a non-renewable energy source.
The principal fossil fuels are oil, coal, and natural gas. Our economy is based on their consumption. They account for 88% of the total primary energy consumption.
Fossil energy is the most used worldwide. We use it in transportation, electricity generation, heating houses, and more.
Coal was the first type of fossil fuel used, followed by oil, and finally by natural gas.
Some scientists predict that fossil fuels will be depleted within 200 years.
1. Theoretical Bases
Coal
Coal is a solid combustible black or brownish-black substance.
It is composed primarily of carbon along with variable quantities of other elements, principally hydrogen, sulfur, oxygen, and nitrogen.
It is formed from plants that died millions of years ago. The plants settled on the seabed and were gradually covered by many layers of earth and rock.
Very high pressure and temperature caused the plants to transform into coal.
It is mined by drilling through the rock.
It is most commonly used for generating electrical energy and is essential for iron and steel production.
Oil or Petroleum
Oil is a combustible substance formed by hydrocarbons.
Its color varies between amber and black. The etymological meaning of the word “petroleum” is “rock oil” because it has the texture of an oil and is found in sedimentary rock deposits.
Oil is formed from marine animals that died and settled on the seabed. Many layers of earth and rock formed above them, and the high pressure and temperature transformed them into oil over millions of years.
It is naturally present in sedimentary rock deposits and only in places where there were ancient seas.
Miners drill through the layers to extract it.
It is used for various purposes, including home gases (like butane), gasoline, naphtha, kerosene, diesel, lubricants, waxes, fats, asphalt, and more.
Natural Gas
It is the only fossil fuel that is a gas.
It is composed primarily of methane.
It is colorless, non-toxic, and lighter than air.
Natural gas is formed in the same way as oil.
We can find it in oil fields, dissolved or associated with oil, or in coal deposits.
Some uses of natural gas include steam generation, electric generation, central heating, air conditioning, hot water, and cooking.
Electricity
1. Fossil fuels are transported to power plants.
2. The fossil fuels are burned to heat water, breaking many hydrocarbon bonds and releasing large amounts of energy.
3. The steam from the water increases in pressure, forcing a turbine to rotate.
4. The turbine rotates a magnet encased in a generator at high speeds.
5. As the magnet rotates, electrons are produced, powering the electricity grid.
2. Advantages
2.1 Coal
- We obtain a large amount of energy in a simple way.
- Low transportation cost.
- Safe transportation, storage, and production.
2.2 Oil
- Produces energy regularly with good performance.
- Has many uses in modern life.
2.3 Natural Gas
- Its combustion does not leave waste.
- Abundant reserves.
- Its extraction, transportation, and burning are economical.
3. Disadvantages
3.1 Coal
- Extraction is dangerous.
- Non-renewable, so it will be depleted in the future.
- Contributes to pollution, the greenhouse effect, acid rain, and altered ecosystems.
3.2 Oil
- Becoming more expensive.
- Handling is dangerous.
- Contributes to pollution, the greenhouse effect, acid rain, and altered ecosystems.
3.3 Natural Gas
- Produces pollution (but less than other fossil fuels).
- Storage is difficult.
- Contributes to water pollution.
- Dangerous to work with as a combustible material.
4. Environmental Impact
Combustion of fossil fuels produces CO2 and other air pollutants, such as nitrogen oxides, sulfur dioxide, volatile organic compounds, and heavy metals.
As they produce CO2, a greenhouse gas (a gas that traps the sun’s heat), it contributes to global warming (a gradual increase in the earth’s temperature). Some people argue that global warming is a natural phenomenon, but human activities like the combustion of fossil fuels are accelerating it. Therefore, we must find alternative renewable and profitable energy sources because we only have one Earth, and we must care for it.
Fossil fuels also contain radioactive materials, mainly uranium and thorium, which are released into the atmosphere.
In the United States, more than 90% of greenhouse gas emissions come from the combustion of fossil fuels.
One consequence of fossil fuel combustion is acid rain, which impacts natural areas.
We consume 3.2 billion tons of carbon per year, more than 2.5 million metric tons of carbon in power plants alone. The U.S. consumes 20 million barrels of oil and 1 million tons of coal per day.
5. Cost
The cost of fossil fuels has increased significantly in the 21st century.
Fossil fuels are cheap per kilogram, but you need to use many kilograms to obtain energy.
The extraction of fossil fuels is cheap, but their processing is expensive and can create conflicts.
Classification of fuels from cheapest to most expensive:
- Biomass
- Fossil Fuels
- Nuclear Fuels (plutonium)
Because there are many types of fossil fuels, there are different costs:
5.1 Natural Gas
Most of the natural gas consumed is extracted in Russia, so transportation is somewhat expensive.
Its extraction is economical.
5.2 Oil
The unit of measurement for oil is the barrel, which is approximately 159 liters.
The main costs of oil are transportation and processing.
A barrel of oil cost about $35 in 2008, but prices are constantly increasing.
5.3 Coal
Coal is very cheap because it is abundant and has easy extraction and processing.