Most of the energy we use to power technology come from finite sources which are not sustainable. This energy which may be in the form of either fossil fuels, coal or even nuclear fuels and so on will eventually be used up. However renewable sources such as solar power will not run out…..until the sun runs out of hydrogen fuel but that’s another story.
We are able to harness the light energy radiated by the sun by the used of solar cells. A solar cell is an electronic device made of semiconductors which exhibit the photovoltaic effect to convert light energy into electrical energy. Semiconductors are materials which lie between conductors and insulators. A conductor is a material which is composed of atoms in which electrons are easily freed from the nuclei. Even though it is able to form a current, it remains electronically neutral as there are the same number of positive protons and negative free electrons. An insulator, on the other hand, is a material which is composed of atoms which hold more tightly onto their electrons so they have no free electrons like conductors. Current is a measure of the rate of flow of charge through a material, with the electrons being the charge carriers transporting energy across a circuit. Continue reading