The Solar Panel

Changes Sunlight into Electricity

A solar panel (or several of them) is the heart of your system for collecting and making use of solar power.

Some simple solar panels are used to heat water which is then stored in hot water systems for hot showers, baths and other purposes.

Electric solar panels are made up of a collection of solar cells which are commonly made of silicon. When light hits these photovoltiac (PV) cells, a tiny electrical current is produced. The light is transformed into electricity. The crystalline silicon cells are very fragile, and have to be protected from accidental damage by covering them with thick protective glass at the front and a panel at the back. The whole arrangement is then surrounded by a steel of aluminium frame, and rubber or silicon seals to keep out the weather.

Enclosed PV solar panels provide protection from rain and hail. They are usually mounted on the roof of your house or other building (on a frame of metal or wood). Sometimes the solar panels are mounted at ground level in a clear area nearby. The solar panels are normally oriented so they face the sun at midday (12 pm, noon). In the northern hemisphere then, they would face South. And in the southern hemisphere, such as Africa, South America, Australia and New Zealand, the panels need to face North.  

Solar panels contain numerous individual pv cells which are wired together in a configuration that is measured both in DC (direct current) Volts and Watts. Manufactured solar panels are rated by Volts and Watts to make it easier to quantify the power they can produce for you.

A typical solar electric panel might be rated as 12 volts DC and 100 Watts. That's commonly referred to as a 100 watt solar panel. The 100 Watts sounds like a lot of power, but that's only equal to the output of a single bright household light bulb (the old fashioned tungsten filament globe). All but the most modest solar homes are sure to need several such pv panels connected together to meet their requirements for basic household electric power.

Solar panels can be wired in series or in parallel, or in combinations of series and parallel. Thus two 12v 100W panels could be used to supply either 200 Watts at 12 volts, OR 100 Watts at 24 volts. Four 12v/100W panels could provide you with 48 volts at 100 Watts, or 12 volts at 400 Watts, or even  24 volts at 200 Watts. it all depends how they are connected together.

Next: Solar Electricity