Question: How is light transferred into electricity?

Kieren Bradley answered on 13 Mar 2014:

A few different ways, the way I am doing it you have to think of light as billions of particles. Each of the particles has a different amount of energy that depends upon what colour it is. In materials called semiconductors (halfway between metal conductors and plastic/wood/ceramic etc insulators). I like to imagine the solar cell a bit like a river with a water wheel; when light hits the bottom of the river it lifts the water to the top of the river (or in our case gives electrons in the semiconductor energy). The water then rushes back down the river but goes past a water wheel and turns it round (instead it is electrons flowing around an electric circuit and powering a motor/LED/TV etc.) In fact the water wheel is actually a form of solar power, if you’ve done the water cycle you’ll know it is the sunlight that turns the sea into clouds which then rain onto rivers and turn our water wheel before getting back to the sea.

Another way of turning sunlight into electricity is to use its heat. We can get fields of mirrors and use them all to shine light onto some water. The water will turn into steam and rush through a generator to create electricity by spinning a magnet which makes electrons move in an electronic circuit.