Walking down the streets, you might have seen big solar panels installed on houses and hotel terraces. And looking at them, most of us are filled with curiosity – how do solar panels work? While it seems like rocket science initially, the concept is easy to understand.
Solar panels capture the sun’s energy and turn it into electricity for our homes, offices, or apartments. That’s what we know so far. However, understanding the entire operating mechanism of solar panels will add to your knowledge. So, next time someone asks you the same question, you have a better explanation.
Let’s talk about how solar panels work. As you have probably heard in your science class, the sun is a nuclear reactor that releases photons, tiny packs of energy. These photons travel about 149.6 million km to reach Earth in approximately 8.5 minutes. You will be surprised to know that the amount of photons that reach Earth every hour is enough to complete the world’s energy need for an entire year.
It is a common myth that solar panels generate electricity all the time, but that’s not the truth. It generates electricity when we need it the most, during the hot sunny weather and summers when the electricity demand is at its peak.
Components of Solar Panels
Solar panels are key components of any solar power system. But they are not the only ones that work; there are other components, too. So, let’s take a look at them:
- Solar Cells: These silicon cells convert the sunlight into power.
- Backsheet, Encapsulation, and Frame: A polymer encapsulation, an insulating back sheet, and a meta frame hold dollar cells and prevent them from touching other elements.
- Junction Box: The box protects wiring connections, diodes, and other power components.
- Connectors: A complete solar power system has MC4 connectors connecting all solar panels and other components.
Apart from these solar panel elements, there are other components that connect panels to your home’s electricity grid system.
- Inverter: A solar energy system needs an inverter to work correctly. The inverter changes the type of electricity that solar panels and batteries produce. Solar panels and batteries make direct current, or DC, which flows in one direction. Home appliances and outlets use alternating current, or AC, electricity flowing back and forth. The inverter transforms the DC power from solar panels and batteries into AC electricity for home use.
- DC Optimizers and String Inverters: DC optimizers let each panel work separately and run MPPT (maximum power point tracking) on each solar panel. The optimized electricity is then fed to a string inverter to transform it into AC power.
- Microinverters: Just like DC optimizers, these devices let each panel work independently and invert DC to AC, eliminating the need for central inverters.
- Rapid Shutdown Device: These devices are responsible for the safe shutdown of the system.
- Telemetry Hub: These devices communicate and monitor the solar power system’s performance.
- Battery: If your solar panel system is connected to the grid, you won’t require a battery. A battery lets you store electricity and use it later. You need a battery if you want to disconnect from the grid or if you want your solar panels to keep your home running during a blackout.
How Do Solar Panels Work?
Solar panels are just the phase of the entire electricity generation process. Apart from these panels, the system has several other components that help these panels to generate power for your home. To help you in understanding the process of how solar panels work, here’s a step-by-step breakdown of the process –
Solar Cells Absorb the Photons
With sunlight hitting the solar panels, the photons it carries are absorbed into the solar cells. The photovoltaic effect converts these photons into electric current. This energy is transformed into direct current (DC), then into alternating current electricity (AC) through a solar inverter to work in your home.
Conversion of DC Energy to AC Energy through Solar Inverter
While direct current (DC) can be used in your homes, it gets converted into AC through solar inverters. Most solar panels are equipped with string inverters. They combine multiple solar panels to convert power. Some solar panels come with microinverters attached to each panel but can be a more expensive option than a string inverter.
Usable Energy Flows to Your Home
Following the conversion of DC energy into AC, the power then travels to your home’s main electrical panel. It is similar to grid system electricity. You can decide whether to tie the power to the grid or not. If you stay connected, you can use grid power when your solar panels are not producing enough electricity. If you go off-grid, you need to have a solar system that can power your entire home without any grid connection.
A Net Meter Monitors Your Electricity Use
A net meter monitors your electricity flow from the grid when social panels aren’t available. These net meters also keep track of any excess power generated by your solar panels. These devices are particularly beneficial for people who sell their excessive solar power in exchange for annual payouts or utility bill adjustments. However, the availability of these programs is subject to different states. You can find these programs offered by local power suppliers.
Solar Batteries Store Your Excess Power
Solar panels absorb sunlight and convert it into DC electricity, which then goes to an inverter that changes it to AC electricity for your home. If it produces more electricity than you need, you can store the excess in solar batteries. These are very useful if you want to disconnect from the grid or avoid net-metering programs.
You can use the stored electricity when there is a power outage or when your solar panels are not working. You can also save money by using the stored electricity when the electricity rates are high. Solar batteries are not required for solar systems but are a good option.
The Process of Solar Panels Making Electricity
As we have discussed earlier, solar panels generate direct current (DC) power. DC electricity has electrons that flow only in one direction along a circuit. For example, a battery can light up a bulb with DC electricity. The electrons go from the battery’s negative side, through the bulb, and back to the battery’s positive side.
AC (alternating current) electricity makes electrons move back and forth, changing direction from time to time, like the piston of a car’s engine. AC electricity is made when a wire coil spins near a magnet. There are many ways to spin this coil, such as using gas or diesel, nuclear energy, water power, coal, wind, or solar.
Indian electrical power grids use AC current that flows throughout the homes in the country. As solar panels generate DC current, what makes it convert into AC is an inverter.
What Does a Solar Inverter Do?
The solar panel produces DC electricity from sunlight. Later, the solar inverter converts this DC electricity into AC current that your home appliances can use. The solar inverter is also the smart part of the system. It does more than just change DC to AC power. It also protects the system from ground faults and shows the system’s performance, such as voltage and current on AC and DC circuits, energy output, and maximum power point tracking (MPPT).
Solar power systems rely on central inverters to change the DC electricity from the solar panels into AC electricity for the home. But now, there is a new technology that changes the game: micro-inverters. Micro-inverters work differently from central inverters.
They adjust the power for each solar panel individually, not for the whole solar system. This means that every solar panel can work at its best.
With a central inverter, if one solar panel has a problem (maybe it’s covered by shade or dirt), it can affect the performance of all the other panels. But with micro-inverters, each panel is independent. If one panel has an issue, the rest of the panels are not affected.
Is It Worth Installing Solar Panels at Your Home?
Solar energy is becoming more popular as people are looking for ways to save money and protect the environment. The best usage of solar energy is to install solar panels on your roof. Solar panels can offer clean and renewable electricity that can reduce your dependence on the grid.
But are solar panels a good investment for your home? The answer is YES. Solar panels have many advantages besides lowering your electricity bills. Solar panels are also durable and reliable and can increase the value of your home. However, you need to make sure that you buy solar panels from trustworthy installers who can offer you quality products and services.
The solar panels are the most important part of your solar power system. They determine how much electricity to produce and save.
Therefore, you should understand how solar panels work before you buy them. This will be particularly helpful for you to decide responsibly as a customer.