coal power

definition

Coal has been used for centuries; the most primitive use was burning it for heat and light. Coal is created from dead plants and animals that have been compressed under the earth for millions of years. Australia is one of the world's biggest producers of coal. Nowadays, Australia derives more than 80% of its energy from coal and is the world's largest coal exporter. Because of the abundance of coal in Australia's mineral-rich land, electricity generated from it is relatively cheap in comparison to other countries.

how coal power works

After the coal has been mined, it is pulverised in to a fine powder. It is then mixed with hot air and then blown into the combustion chamber of a boiler where it is burnt at extremely high temperatures c.1400°C. The heat produced by the burning coal heats water in the boiler, which creates steam. The steam in turn rotates turbines, which power a generator. The steam is then cooled as it travels through the turbines and converted back into water, and finally returned to the boiler where the process begins again.

advantages of coal power

There are some advantages from using coal to generate electricity:

• Coal reserves are abundant in Australia and the mining of these resources is well established
• Coal is a reliable and relatively inexpensive form of energy
• Coal is a highly developed source so large amounts of electricity can be generated at low cost
• Coal fired power stations can be built almost anywhere and the coal brought in by rail

disadvantages of coal power

However, coal has some significant disadvantages:

• Coal power produces more carbon dioxide than any other form of fuel and is one of the leading contributors to the "greenhouse effect", warming the earth
• Although coal is abundant, it is not a renewable energy source and will eventually be depleted
• Burning coal causes acid rain in some countries due to its high sulphur content
• Mining coal is very damaging to the land and can cause permanent environmental damage