What is a fuel? Give five examples of fuels and what are the characteristics?

A fuel is any combustible substance that produces heat or energy when burned. Common examples are wood, coal, petrol, diesel, and natural gas. A good fuel should have a high calorific value, be readily available, affordable, easy to handle and transport, contain low moisture, and generate minimal harmful byproducts on combustion.

What is a Fuel?

A fuel is a substance that, when it reacts with oxygen (usually through burning), releases energy in the form of heat and light. This energy is harnessed for everyday uses such as cooking, heating, electricity generation, and running vehicles.

Five examples of fuels:

1. Wood
2. Coal
3. Petrol
4. Diesel
5. Natural Gas

Characteristics of a fuel:

1. High Calorific Value – Should release large amounts of energy per unit (e.g., petrol, diesel).
2. Easy Availability – Readily accessible and sufficiently available in nature or through production (e.g., coal, natural gas).
3. Low Cost – Affordable for widespread use (e.g., natural gas, coal in some regions).
4. Ease of Storage and Transport – Should be safe and convenient to store or move (diesel is safer to transport than petrol).
5. Low Moisture Content – Especially important for solid fuels like wood and coal for efficient burning.
6. Clean Combustion – Should produce minimal smoke, ash, or harmful gases (natural gas is the cleanest among the examples).
7. Controlled Ignition Temperature – Should ignite under controlled conditions without being too difficult or too dangerous.