Petrol and diesel extracted from crude oil are commonly used to run different kinds of vehicles, such as cars, buses, tractors, trucks, trains, and aeroplanes. Similarly, kerosene and natural gas are used as fuels in lamps and stoves. Crude oil, coal and natural gas occur in limited and exhaustible quantities. They cannot be regenerated in a short period of time or used again and again. Hence, they are called non-renewable sources of energy.
At present we get most of our energy from non-renewable energy sources which include fossil fuels such as coal, crude oil and natural gas. Looking at the present and future energy requirements, it is expected that oil and natural gas reserves may last for another 30-35 years. Similarly, the coal reserves may last no longer than another 100 years. So, we must use these non-renewable energy sources judicially and avoid all wastages.
Radioactive elements like natural uranium are also non-renewable. When the atoms of uranium are split into two or more parts, a very large amount of energy is released which can be used to generate electrical energy.
Fossil fuels, such as coal, oil and natural gas, are important non-renewable sources of energy. Since the beginning of mankind, we have been using fossil fuels to generate heat, light and electricity for various purposes. These are the primary sources for generating electrical energy in the world today.
Carbon is the main constituent of these fossil fuels. Fossil fuels are excellent sources of energy for our transportation needs. A large amount of chemical energy is stored in the fossil fuels. This stored chemical energy is converted into various other forms of energy such as heat, light and mechanical energy.
How the fossil fuels are formed? Millions of years ago the remains of dead plants and animals were buried under the ground. Over the years by the action of heat from the Earth’s core and pressure from rock and soil, these buried and decomposed organic materials have been converted into fossil fuels.