Solar Basics

The Solar or Photo Voltaic (PV) industry continues to grow rapidly  . Sunlight, the source of solar electrical energy is one of the cleanest sources of power ever tapped by technology. Needless to say , it is smart to know at least the basics of this exploding industry.

In order for us to power our tools, appliances , computers and electronics, we have to have electrical current or flow of electrons coming from our wall outlets to our gadgets. This same flow of electrons are normally produced from electromagnetic or electrical generators using the basic electromagnets and conductor (coils of wires ) combination .  These are still king in electrical production.

But here is the catch. Electromagnetism plus coils of wires do not produce electricity until there is relative motion such as rotation between the two elements.  And yes, rotation of machinery need power to make it happen ! Mechanical rotation need prime movers to create such motion.  So we use diesel engines , steam turbines , hydro turbines , windmills . Steam turbines are driven by high temperature steam that are produced using coal , jet fuel, natural gas , nuclear power .  So you see these systems take years and millions of dollars to build and maintain. Not to mention the mess that they leave behind!

Now comes solar power! This baby does not need magnetics or coils of wire to produce electricity. It does not have any rotating members. As a matter of fact it has NO MOVING PARTS! It is quiet , clean and one cannot even hear it hum.
And it can produce MegaWatts (MW) or millions of watts just by exposing the solar cells to the radiant sun!

Current solar cells use silicon-based material to produce electricity! It is as simple as the sun's rays composed of what are known as photons hitting the surface of the cell , then this process 'excites' the loose or free electrons of the cells , creating an electron flow. These individual electron flows from each cell are collected and directed out of the cells or panels , into wires and to the inverters.

And what in the world are inverters? They are electronic devices that convert the DC (direct current) produced by the PV panels into usable AC (alternating current) that is the same as the power we have in our homes. Inverters are also very efficient and quiet since they are all electronics.

Inverters are of two basic types: Grid-tied or Off-grid. Grid is the word used to describe the huge network of electrical systems supplying communities . Grid-tied means the solar electrical system is connected to the community or utility power . Off-grid are just that, they are on their own, self-sustaining supported by banks of batteries. Batteries are DC voltage sources similar to the DC from solar panels.

There are a few more components that make up the solar electrical system. But the solar panels and the inverters are the two main components.

Joe Joson
California, USA