Most of the electricity we use each day comes from a power station. Large fan-like machines called turbines turn to create electricity. The electricity reaches us by travelling along wires strung from power poles or towers, or run underground. This allows us to switch on our lights, heat and cool our homes and use our appliances.
The most common way of producing electricity is by using fossil fuels. There are three main forms of fossil fuels: coal, oil and natural gas.
These fuels were formed millions of years ago, long before the dinosaurs. The remains of plants and animals settled to the bottom of lakes and oceans and were covered by sand and mud.
Over millions of years, the earth's pressure and heat turned the layers of earth into a hard rock-like substance called coal, a thick liquid called petroleum, or an invisible substance called natural gas.
To begin the process of converting fossil fuels into electricity these substances need to be taken out of the ground. Coal mines bring the coal up from underground, while massive drills collect the oil and gas. Coal produces around 64% of the world's electricity, with the remainder coming from water, gas, nuclear and green sources. Most developed countries rely heavily on coal for power.
Coal is a non-renewable resource (which means it will eventually run out), but at current usage there is enough coal in Australia to last for another 700 years or more. Despite this, it is important we preserve it and look for more environmentally friendly ways of producing electricity.