According to the law of conservation of energy, it can neither be created nor be destroyed, it can only be changed from one form to another. Thus, we cannot produce energy to do certain work. Therefore we use certain substances which help us transform one form of energy to another form.
For example, when we burn paper with a matchstick, light is produced by the flame. If we analyze this closely, light energy is not created over there, it has just been produced due to the transformation of heat energy provided by the matchstick into light energy.
Thus, we always need a certain substance to convert one form of energy into another for accomplishing various jobs. We call such materials as fuels. In other words, any substance which upon combustion produces a usable amount of energy is known as fuel. Example: fossil fuels, biogas, nuclear energy, etc.
Renewable source of energy: one which is inexhaustible. Example: Solar energy.
Non-renewable source of energy: one which is exhaustible. Example: Fossil Fuels.
Now, the energy produced by burning paper is not sufficient to run cars but energy produced by burning petrol is enough to do so. Thus, we can say that each fuel releases its own set of energy i.e. all of them do not release the same amount of energy upon combustion. The energy produced by combustion of one kg of fuel is known as its calorific value.
Thus, we can differentiate different fuels on the basis of their calorific value for their efficient usage. Furthermore, each of them has a different cost with respect to another. Some are cheaper while others are expensive. Therefore we categorize fuel as an ideal based on different criteria.
|Tanbark, Bagasse, Straw,
|Petroleum||Oils from distillation of petroleum,
|Natural Gas||Coal gas,
Water Gas, Hydrogen,
Blast Furnace Gas,
Fuels which are found in their solid state at room temperature are generally referred to as Solid Fuels. They were the first kind of fuel known to be used by man, basically wood to create fire. Coal was another one of the influential fuels known to man as it leads the way for the industrial revolution, from firing furnaces to running steam engines.
Most liquid fuels are derived from the fossilized remains of dead plants and animals by exposure to heat and pressure in the Earth’s crust. The fumes of the liquid fuel are flammable instead of the liquid.
Gaseous fuels occur in nature, besides being manufactured from solid and liquid fuels. Most gaseous fuels are composed of hydrocarbons, carbon monoxide, hydrogen or a mixture of them all.
Fossil fuels are the dead and decayed remains of plants and animals subjected to decades of pressure and temperature under the earth’s crust. Primarily fossil fuels are hydrocarbons. They are convenient and effective. They provide the calorific value required to fulfill our needs. Even though they are available in plenty right now, they are a non-renewable source of energy. The burning of fossil fuels is responsible for a large section of the world’s pollution index.
Nuclear Fuel Element
Any material consumed to give out nuclear energy is a nuclear fuel. Technically speaking, any material can be made to give out nuclear energy. But looking at its practicality and feasibility, we pick materials which do not require extreme constraints to release nuclear energy.
Most nuclear fuels contain heavy fissile elements that are capable of nuclear fission. When these fuels are struck by neutrons, they are in turn capable of emitting neutrons when they break apart. This makes possible a self-sustaining chain reaction that releases energy at a controlled rate in a nuclear reactor or with a very rapid uncontrolled rate of a nuclear weapon.
Some common examples of nuclear fuel are uranium-235 (235U) and plutonium-239 (239Pu).