HOW SOLAR ENERGY WORKS
Make your home your personal power plant!
Solar photovoltaic (PV) systems – also known as solar panel systems, solar energy systems, or solar power systems – convert sunlight into electricity. You can use the electricity generated by your solar PV system to power your home, your business or even your car.
PV systems are made up of a number of components, the biggest and most important being: the solar panels, solar inverters, mounting platforms and cabling infrastructure. Combined, these components harness radiant light from the sun, convert it into electricity and transmit it into homes and businesses to power electrical devices, like lights and appliances, and provide heating and cooling via the electrical currents they create.
Here is a general overview of how solar PV systems work.
Solar panels can come in all shapes and sizes, but they’re typically comprised of a grouping of solar cells that are wired together and encapsulated by a glass casing that protects the equipment against the elements. Solar cells are essentially made up of semiconducting materials – often silicon – that are sandwiched together between positive and negative charges. When sunlight hits a cell, the photons within the sunlight knock electrons free from the semiconducting material. This starts the flow of electricity. Then, conductive plates made of metal on the sides of the cells gather the electrons and transfer them through wires. At this point, these electrons can flow just like direct current (DC). This is known as the photovoltaic effect.
The more solar cells and larger the solar panel array is, the more electricity can be generated.
The solar panels are affix to the roof or to the ground using racking and mounting systems. They also allow you to position your panels at an angle that is best for capturing the sun’s rays. To perform at their best, solar panels should face south and be installed at an angle between 30 and 45 degrees, depending on how far you are from the equator.
Next, a series of cabling infrastructure is necessary to actually bring the raw electricity to the inverters, and to bring later the converted power into homes and business.
Cabling networks can vary, but typically are designed to be UV and weather resistant and capable of dealing with extreme fluctuations in temperature (both heat and cold), since one common factor for these system is that they’re used outdoors. To achieve this, most solar cables use plastic that are cross-linked using electron beams. This protects against the weather elements, including the sun’s radiation and humidity.
Inverters are also considered the “brains of the system”, they have the ability to convert electrical converts back and forth between DC power (used to power devices in the home) and AC power (to put electricity back onto the grid)
There are three general types of solar inverters:
- Stand-alone inverters are those that do not need to be plugged in to an electrical device. Instead, they draw their charge from a battery powered by the solar PV system itself.
- Grid-tied inverters are compatible with the utility grid.
- Battery backup inverters also draw energy from a battery, but what is unique about them is they’re designed to export excess energy back to the utility grid.
Finally, the performance monitoring systems provide you with detailed information about the performance of your solar panel system. With a meter, you can measure and track the amount of electricity (kWh) your system produces, used or sent to the utility on an hourly basis.
When the sun isn’t providing any power for your panels (like at night), your utility provides you with electricity. During the day, if your system is creating more power than your home needs, the extra energy goes into your utility’s power grid.