Types of fuel

• A fuel is any type of material that can be made to react (commonly with oxygen) and release energy in the process
• Fuel provides energy to a body/machine to do work
• Fuels contain energy stored in a chemical form
• The stored chemical energy is converted into heat energy when the fuel is burnt
• Most carbon compounds can be burnt in air (oxygen) to produce carbon dioxide and energy
• Most carbon compounds can thus be used as fuels
• There are different types of fuels
• There are solid fuels
• liquid fuels and
• gaseous fuels

Solid fuels

Coal. Image credit alphabetics.info

• Include wood, charcoal, coke and coal
• Wood is popular in rural parts of Zimbabwe and Africa
• This is because it is cheap despite its low energy content
• It burns quickly making it inefficient
• It produces smoke
• It leads to deforestation
• Charcoal is more efficient than wood
• Charcoal is made by heating wood to very high temperatures in the absence of air
• Wood is pile up
• Covered with soil and grass before being ignited(set alight) through a small hole
• Some of the wood burns, heating the rest in the process and converting it to charcoal
• The resulting charcoal is nearly pure carbon
• It is a porous, black substance
• Coal also has a higher carbon content than wood and is thus more efficient
• It also has a higher heating/energy value than wood

Liquid

• Common liquid fuels include:
• alcohol, ethanol, petrol, diesel and paraffin
•  Petrol, diesel and paraffin are all obtained by distilling Petroleum
• Petroleum is also known as crude oil
• All the fuels that are obtained from the distillation of crude oil are called hydrocarbon fuels
• This is because their molecules contain only carbon and hydrogen atoms
• Ethanol is produced at Triangle in Zimbabwe
• Sugar is fermented
• Ethanol is added to petrol/motor fuel to make Blend Petrol
• It is also used in in Meth burners

Gaseous fuels

A gas flame. Image credit imperial.ac.uk

• Examples of gas fuels include Natural Gas, Petroleum gas (often known as Liquid Petroleum Gas or LP gas) and Biogas
• These gases usually contain propane and/or butane
• Gases are usually cleaner,
• and easier to control as they can be tapped to desired locations
• They also do not contain contaminants which might leave solid residue

To access more topics go to the Combined Science Notes page.