A renewable energy resource is one that is being (or can be) replenished as it is used.

A lot of our energy comes from non-renewable sources such as coal, oil and gas. These resources are made up from the remains of ancient animals and plants that develop over millions and millions ...

Renewable energy sources are plentiful and all around us. Fossil fuels - coal, oil and gas - on the other hand, are non-renewable resources that take hundreds of millions of years to form.