General P.V. Solar Information + Click to enlarge
How do P.V. Solar Panels Work?
Anyone who has used a modern mathematical calculator can grasp the concept of photovoltaic (PV). It is simply the process of converting energy from the Sun into electricity that can power everything from household appliances, lights, sprinkler systems and water pumps to large-scale communications, industrial and military equipment.
In precisely the same way as the small solar cells on hand-held calculators eliminate the need for batteries, PV can provide the world with a clean, reliable source of electricity and reduce our reliance on ever-depleting fossil fuels.
The PV technology of the 21st Century makes it possible. It employs layers of micro-fine crystalline silicon to convert ordinary sunlight into small electrical charges. This process is then multiplied thousands of times over to create modules and systems that can generate enough electricity to power entire towns.
It's important to note that PV is different from the 'passive' solar thermal energy used for heating or in hot water production. A single PV cell consists of two or more thin layers of semi-conducting material, most commonly crystalline silicon. When the silicon is exposed to light, small electrical charges are generated and conducted away by metal contacts as direct current (DC).
In order to maximise energy collection and conversion, single cells are connected together and housed in a module. These modules are the building blocks of PV systems and are, in turn, connected together to generate usable volumes of electricity. In some instances, an inverter is also used to convert low voltage DC into higher voltage AC power.
Types of PV Cells
There are essentially two types of crystalline silicon PV cells:
Monocrystalline - These are made using cells cut from a single cylindrical crystal of silicon. While monocrystalline cells offer the highest efficiency (approximately 18% conversion of incident sunlight), their complex manufacturing process makes them slightly more expensive.
Polycrystalline - These are made by cutting micro-fine wafers from ingots of molten and recrystallised silicon. Polycrystalline cells are cheaper to produce, but there is a slight compromise on efficiency (approximately 14% conversion of incident sunlight).
Storage of Energy
The solar energy generated from the PV Panels is stored in your battery bank, ready for use when required. If this energy was not stored, then at night when there is no sun to produce electrical energy or when you require larger amounts of energy than the panels can produce at one time, you will find yourself without any power.
The amount of storage required will depend on your daily usage, the amount of PV panels installed, your location and the amount of reserve required for times of bad weather.
An Interesting Fact
The sun can produce enough solar energy in a day to power the world for a whole year and in time with technology advances we will learn how to harness that energy more and more efficiently.
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