The Sun is a star and without it there would be no life on earth. This is why the Sun is called the ultimate source of energy. The Sun’s energy is produced by a process called nuclear fusion. Every second, the Sun emits vast amounts of energy, much of which is light, and this solar radiation can be converted into electricity.
Plants and trees are pretty good at collecting this energy. With the help of green chlorophyll, they use light energy to make food – they’re our solar powered food factories. But how can we copy them?
Scientists and engineers are working on ways to do this and have developed photovoltaic cells, or PV cells for short, that can turn sunlight into electricity. Originally developed to power satellites in space, PV cells are combined in solar panels and mounted on the roofs of buildings. They can also be used to power devices such as calculators and watches.
Sunlight lands on layers of special materials that are designed to create the electrons that are needed for electricity. When these sunlit materials are connected to circuits, electricity flows. We can’t get very much power from PV cells yet, but the technology is improving all the time and although we’ll never be able to catch all the power from the Sun, we may be able to get enough to power some of our favourite devices.
We can also store the energy generated by solar cells in batteries to use at a later time. Storing energy in batteries is not very efficient, but it is useful, so many solar-powered devices have a battery too that stores energy when it’s sunny to use when it’s dark. The Sun is stronger in hot countries so solar power works there, but it also works when it’s cloudy. So long as there is light, solar power can work.
Key Facts
Solar energy is plentiful, free and renewable.
Solar panels do not produce any carbon dioxide emissions when converting solar power into electricity.
Solar power can be used to create electricity in remote places