This brief course is a part of the solar photovoltaic project development.
From Atoms to Electricity
All matter is made up of atoms, and atoms are made up of smaller particles called protons, neutrons and electrons. The center or nucleus of an atom is made up of protons and neutrons. The electrons orbit around the nucleus just like the moon orbits around the earth. Electrons have a negative charge, while protons have a positive charge and neutrons are neutral.
Electricity is created when particles become charged. Some are negatively charged (electrons), and some are positively charged (protons). These opposite charges attract, whereas particles with similar charges repel each other.
When an electrical source (such as a battery) is attached by a wire to a form of resistance (such as a light or motor), and a circuit is completed back to the source or to the ground, free electrons are released into the wire, creating an electrical potential or voltage. The electrons bounce against other electrons in the wire, which are repelled because they have the same electrical charge. They go on bouncing against other free electrons down the wire, causing a flow of electrons-an electrical current. Provided there is somewhere for the electrons to go and be converted into another form of energy (such as inside a light or motor), the electrons will flow out the far end.