Sources of Energy

Fossil Fuel

Fossil fuel include coal, oil and natural gas. Their formation dates back to million years ago from the remains of living organisms. When we burn them, they release energy. Further, they are non-renewable. Let’s dig in deeper about these non-renewable substances.

fossil fuel

Definition of Fossil Fuel

The buried flammable geologic deposits of organic substances like dead plants and animals which are deposited under many thousand feet silt are known as fossil fuels. Basically, these deposits kept decaying as the time passed by and then turned into natural, gas and petroleum.

This happened because of extreme heat and pressure inside the crust of the earth. We also refer to them as non-renewable sources of energy because it takes a long time for replenishing.

Types of Fossil Fuel

There are three major types of fossil fuels, they are coal, petroleum and natural gas. Coal is a hard substance which is black in colour composed of carbon, hydrogen, nitrogen, oxygen and sulphur.

Furthermore, petroleum is a clear and oily liquid in the colour of green or black. Finally, natural gas is a clean and non-toxic fossil fuel. We will now study these three in detail.


Industries process coal for obtaining derivatives such as coke, coal tar and coal gas. There are three major types of coal, they are anthracite, bituminous and lignite. The hardest type of coal with a higher carbon concentration is anthracite. Further, one having a high concentration of oxygen and hydrogen but a low concentration of carbon is Lignite. Finally, Bituminous is a moderate form of coal.

Formation and Uses

Millions of years ago, the dense forest in the low-lying wetland got buried in the earth and the soil started depositing over them and they got compressed. Thus, as they started going deeper and deeper, they began to face high temperature and pressure. Consequently, the substances began to slow convert into coal. We refer to the process of forming coal as coalification.

Initially, we made use of coal for producing steam in the railway engines. Further, we also use it for cooking food and generating electricity in thermal plants. Moreover, we also use it in industries as fuel.


Petroleum has quite a strange smell as it is a blend of petroleum gas, diesel, paraffin wax, petrol and lubricating oil and more. We also refer to it as Black Gold because it has a wide range of uses in a lot of industries.

Formation and Uses

The sea animals and plants died and their remains went down to settle at the bottom of the sea. The layers of sand and clay compressed them over time. Further, upon encounter with high temperature and pressure, they got converted into petroleum. We separate petroleum from the crude oil through a series of processes in a refinery. We refer to that as petroleum refining.

Further, we use petroleum to power internal combustion engines in the form of petrol. We also use it in roofing, road pavements and also as a water repellent. Finally, we also use petroleum to manufacture detergents, plastics, fibres, polyethene and more.

Natural gas

Natural gas does not have a colour and odour. We can transfer it easily through pipelines. Further, we store it as Compressed Natural Gas (CNG) under high pressure. In fact, it is a less polluting and cheaper fossil fuel. Most importantly, Methane is the most essential natural gas.

Formation and Uses

Phytoplankton and zooplankton sink and reach the ocean’s bottom and blends with organic materials and form an organic-rich mud. Further, the mud present under more sediments then lithifies and forms an organic shale. Thus, it stops exposure to oxygen for protecting the organic materials from decomposing by bacteria.

The shale transforms into a waxy material called kerogen and between temperature of 90-160°C, it transforms into natural gas. We use natural gas for creating power, as fuel in automobiles, at homes for cooking and as a starting material in chemicals and fertilizers.

Advantages of Fossil Fuel

Fossil fuels have the ability to create a huge amount of electricity at a single location. Moreover, they are found easily and also cost-effective. Further, we can easily transport oil and gas through pipelines.

Over time, they have become safer. Besides, most of our infrastructure is designed to operate through the use of fossil fuels. Finally, even though it is a finite resource, it is available in abundance.

Disadvantages of Fossil Fuel

They emit carbon dioxide, a major greenhouse gas, on burning, which is also a major source of pollution and contributes to global warming. When we burn coal and oil, it releases sulfur dioxide that can cause breathing problems and acid rains. Most importantly, we cannot replace them.

Further, when we burn them, they make the environment more acidic. Consequently, it affects the environment negatively and makes it unpredictable. Being non-renewable energy resources, their limited supply means we will run out eventually.

Moreover, harvesting them results in fatal diseases like coal miners suffer from Black Lung Disease sometimes and natural gas drillers are exposed to chemicals which is also dangerous health-wise.

FAQ on Fossil Fuel

Question 1: What are the types of fossil fuels?

Answer 1: There are three main types of fossil fuels. They are coal, petroleum and natural gas.

Question 2: Are fossil fuels renewable?

Answer 2: No, fossil fuels are a non-renewable source of energy. We burn them to obtain energy and thus are used at a faster rate. With the increased requirement for the creation of different energies, fossil fuel energy is declining. It is difficult to replace them.

Question 3: Which type of fossil fuel produces the most amount of carbon dioxide?

Answer 3: Out of the three fossil fuels, for a given amount of energy released, coal is the one which produces the most carbon dioxide whereas natural gas produces the least.

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Why should we give more emphasis on the uses of non conventional energy sources than conventional sources? Discuss

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