How Do Photovoltaic Cells Work?
Updated: Sep 17, 2019
You have probably seen solar panels on rooftops all around your neighborhood, but do you know how they actually work to generate electricity? In this article, we will take a look at what a photovoltaic (PV) solar cell is. This is the technology behind a solar panel that makes it possible to create energy from the sun.
3 Steps To Generate Electricity
Light is absorbed & knocks electrons loose
Loose electrons flow, creating a current
The current is captured & transferred to wires.
The PV effect is a complicated process, but these 3 steps are the basic way that energy from the sun is converted into electricity by solar cells.
Solar PV Cells Are The Building Blocks of Solar Panels
A solar panel is made up of 6 different components, but arguably the most important one is the PV cell, which actually generates electricity. The conversion of sunlight into electrical energy by a solar cell is called the “PV effect”, hence why we refer to solar cells as “PV”.
Solar PV cells generate electricity by absorbing sunlight and using that light energy to create an electrical current. There are many PV cells within a single solar panel, and the current created by all of the cells together adds up to enough electricity to power up your home. A standard panel used in a rooftop residential system will have 60 cells linked together. Commercial solar installations often use larger panels with 72 or more PV cells.
Type of Solar Cells : Monocrystalline & Polycrystalline
There are 2 main types of solar cells used today, which are monocrystalline and polycrystalline. While there are other ways to make solar cells, such as thin-film cells or organic cells, monocrystalline and polycrystalline solar cells are by far the most common residential and commercial options.
A monocrystalline solar cell is made from a single crystal of the element silicon. On the other hand, polycrystalline cells are made by melting together many shards of silicon crystals. This leads to two key differentiators between mono- and poly- cells. In terms of efficiency, monocrystalline solar cells are generally higher than polycrystalline. This is due to the use of a single, aligned crystal of silicon, resulting in easier flow for the electrons generated through the PV effect. Polycrystalline cells have shards of silicon aligned in many different directions which makes electricity flow slightly more difficult. However, solar panels made with polycrystalline solar cells are usually less expensive than monocrystalline options. This is because the manufacturing process for a polycrystalline cell is simpler and requires fewer specialized processes.
How Does A Solar PV Cell Generate Electricity?
PV cells, through the PV effect, absorb sunlight and generate flowing electricity. This process varies depending on the type of solar technology, but there are a few steps common across all solar PV cells.
Step 1: Light is absorbed by the PV cell & knocks electrons loose
First, light strikes a PV cell and is absorbed by the semiconducting material, which is made from silicon. This incoming light energy causes electrons in the silicon to be knocked loose, which will eventually become the solar electricity you can use in your home.
Step 2: Electrons begin to flow, creating an electrical current
There are 2 layers of silicon used in PV cells, and each one is specially treated, or “doped”, to create an electric field, meaning one side has a net positive charge whereas another has a net negative charge. This electric field causes loose electrons to flow in one direction through the solar cell, generating an electrical current.
Step 3: The electrical current is captured & combined with other solar cells
Once an electrical current is generated by loose electrons, metal plates on the sides of each solar cell collect those electrons and transfer them to wires. At this point, electrons can flow as electricity through the wiring to a solar inverter and then throughout your home.
Many PV Cells Together Produce Solar Electricity For Your Home
A PV cell on its own cannot produce enough usable electricity for more than a small electronic gadget. In order to produce the amount of energy for a home, solar cells are wired together to create solar panels, which are installed in groups to form a solar energy system. A typical residential solar panel with 60 PV cells combined might produce anywhere from 220 to over 400 watts of power.
Depending on factors like temperature, hours of sunlight, and electricity use, homeowners will need varying amounts of solar panels to produce enough energy. Regardless, installing a solar panel system will likely include several hundred solar PV cells working together to generate electrical current. You can contact Solar Era to get an idea of the savings you might see from a solar panel installation.
Install Solar To Start Having PV Cells Work For You
Solar PV cells are the building blocks of solar panels, and any property owner can start generating free electricity from the sun with a solar panel installation. If you feel interest, you can get in touch with our consultant to receive solar installation quote. While the quote involves solar panels made from PV cells, panel output can change based on equipment quality. If you are specifically interested in seeing quotes for high-efficiency solar panels, simply leave a note on your profile for Solar Era to see.