Energy is the fuel that is needed for anything to be able to work. Energy comes in many different forms and is essential for everything we do. The sun is a form of energy- it makes plants grow. Our bodies gain energy from what we eat or drink and cars use petrol for energy.
There are two forms of energy: renewable and non-renewable. Renewable energy is energy from sources that we can use over and over again. Non-renewable energy is from sources that we are using up and cannot recreate in a short period of time.
Renewable energy sources include solar energy (from the sun), hydropower (from water), wind power (from the wind), geothermal energy (created by underground steam) and biomass energy (eg. landfill gases at rubbish tips). Find out more.
Most of our energy comes from non-renewable energy sources, which include the fossil fuels oil, natural gas, and coal. They're called fossil fuels because they were formed over millions and millions of years by the action of heat from the Earth's core and pressure from rock and soil on the remains (or "fossils") of dead plants and animals. 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.
By conserving energy, we reduce the need for electricity generated by coal, and help to minimise what is known as the "greenhouse effect". There are many ways to conserve electricity.