Many have sung praises about solar energy and we’ve also not missed out on highlighting the numerous benefits of solar. Solar is a clean and renewable source of energy with a cost price that has gone down drastically over the years. The benefits that you can enjoy from a home solar panel system are amazing. With all that said, how do solar panels actually work? Let’s take a deep dive into the science — and even history — behind the solar panels that we have today!
A Brief History Lesson
The photovoltaic (PV) effect — the generation of voltage when a semiconductor is exposed to light — was discovered by physicist Edmond Becquerel in 1839. His extensive studies led to him notice a change in the behaviour of electric conductors when subjected to light. Later physicists Heinrich Rudolf Hertz and Albert Einstein further added to his findings. Hertz realised that light intensity affected the number of electrons emitted by electric conductors. Einstein, on the other hand, was the person who came with the concept of photons, the measurement of light that we use today.
Now that we have some background knowledge on the PV effect, we’ll jump right into how the modern-day solar panel works. You’ll realise that the principles of generating solar energy have not really changed that much at all!
Fun fact: Voltage is an electric force that causes free electrons, which have a negative charge, to move from one atom to another through a conducting circuit. This allows the circuit to perform tasks like lighting a lightbulb.
The Science Behind Solar Panels
What exactly are solar panels? Solar panels are made up of a collection of smaller units called solar cells. There are several different types of solar panels, but the most common material used to make solar cells on panels is crystallised silicon. This silicon — a semiconductor material — is stuck between 2 conductive layers that allow for the flow of electrons. The silicon itself is also made up of 2 layers, the N-type layer and the P-type layer. The N-type layer has more electrons and has an overall negative charge. Meanwhile, the P-type later has more electron spaces, or holes, giving it a positive charge. Think of it like a battery that has a minus-end (-) and a plus-end (+).
When researching on the topic of solar, you’ll also notice that solar panels in the market are generally classified as either N-type or P-type. P-type panels used to be more popular because of their better resistance to radiation and degradation in space — that was a time when most of the technological funding for solar panels was driven by space applications. However, the most powerful solar cells in the market today are N-type. They are immune to light-induced degradation due to the absence of boron-oxygen defects. As a result, more and more people are going with N-type panels.
When sunlight hits your solar panels, photons from the sunlight dislodge electrons from the silicon atoms. The electrons then start moving towards the N-type layer (-) and to the conductor that is directly attached to the silicon. This creates current or electricity! This direct current is then channelled to your house’s solar inverter. It’ll be transformed into an alternating current that can be used to power your home.
How are Solar Panels Made?
Making a solar panel is a 4-step process. This starts with the purification of raw silicon (often in the form of silica sand or silicon dioxide) with high heat and chemicals. Once we’ve got pure silicon granulates, they’re then melted and crystallised into silicon ingots. These large pieces of silicon ingots are then sawed into silicon wafers — exactly the shape needed for solar cells. But before assembly begins, some of the silicon wafers are treated with phosphorus and boron to create silicon for the N-type layer. The wafers are also covered with a reflective coating.
Right, next comes assembly! The wafers are sandwiched between metal conductive sheets to create solar cells. Finally, manufacturers arrange the solar cells together and seal between ethyl vinyl acetate (EVA) sheets, along with a tempered glass layer and a back sheet — it’ll then look exactly like a solar panel that you’ll be familiar with!
Solar Energy: The Present and Future
Solar energy is one of the cleanest forms of energy in the world. By using just sunlight, you’re able to generate electricity for usage in your entire home. The process results in no harmful greenhouse gas emissions and is an important step in the right direction in taking a stand against the overuse of fossil fuels. While solar panels require the use of silicon, it’s not a rare material and is the second most abundant in the world after oxygen. What’s more, solar panels have long lifespans of up to 30 years once they are crafted. This makes them a cost-efficient and sustainable energy investment. Take a step in the green direction by finding out your home’s solar potential instantly with our online solar assessment tool right now!
Get an Instant Solar Estimate for your Home Now!
Whether you’re ready to install solar panels on your rooftop, or just wondering how you can benefit from solar, use our instant solar assessment tool to get an estimate of the solar potential of your property and find out how much you can save. At Solar AI, we combine geospatial analysis of satellite imagery with big data and artificial intelligence to provide you with reliable and accurate solar information so that you can make a better solar choice!