How Do Solar Panels Work?
The standard solar panels that you typically see on the rooftops of people’s houses are known as Photovoltaic (PV) solar panels. Photovoltaic simply refers to the process of converting (sun)light into electricity using a semiconducting material (such as silicon).
So how do solar panels work? How do they convert sunlight into electrical energy?
Photoelectric Effect Explained
Solar panels create electrical energy through a process known as the photoelectric effect, which refers to the discharge of electrons from a material when exposed to light. So in the context of solar power, it can be seen as the production of electrical current when the solar panels are exposed to sunlight.
A solar cell (also known as a photovoltaic cell) is a small mechanism converts photon energy (sunlight) into electricity and forms the basic building blocks of a solar panel. A single cell is insufficient for providing enough power for an entire household and must instead be combined with other solar cells to form a solar panel. These solar panels are then attached to other panels to create what is known as a solar array, which is what you see on the rooftops.
How Solar Panels Work
Within each solar cell (see above) there are two layers of silicon which sit directly on top of each other. The above layer has been formulated in such a way that the atoms trapped within it are volatile and desperate to offload surplus electrons. The below layer on the other hand has been prepared in such a way that it has an electron deficit and would welcome the surplus electrons from the top layer. The electrons on the top layer are only too happy to migrate to the lower layer, but there’s one thing that is preventing this from happening; the electrons cannot shift about until the panels are exposed to sunlight.
When solar radiation (sunlight) makes contact with the surface of the top layer, it energises the electrons and causes them to move to the bottom layer, creating an electrical current (photoelectric effect). When two semiconducting materials are placed on either side of the two silicon layers, it produces electricity within a circuit.
Converting DC to AC
At this point, although the solar panels are generating a suitable amount of electricity, it’s direct current (DC). Household appliances require alternating current (AC). In order for the DC electricity to be converted to AC, it must now be processed through a solar inverter.
A Simplified Explanation
- The sun emits light which the solar panels use to generate DC electricity
- The DC electricity is processed by a solar inverter which converts it into AC electricity
- The AC electricity is then able to be used by your household appliances