Non-renewable energy
The most common way of producing electricity is by using non-renewable 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.
Fossil fuels are a non-renewable resources (which means they will eventually run out). Another non-renewable energy source is the element uranium, whose atoms we split (through a process called nuclear fission) to create heat and ultimately electricity.
