Solar cells are devices that turn sunlight into electricity. They’re being used worldwide to provide power to homes and businesses, especially in areas that aren’t connected to the national power grid.
Solar power has been growing as an alternative energy source, but how do solar cells work? What makes them efficient?
Do they store solar energy like a battery? Many people aren’t aware of how solar cells work, though.
The truth is that the process behind solar cells isn’t quite as simple as you might think, but understanding the ins and outs of how they work can help you get even more enjoyment out of your solar panel system.
We will answer questions about solar cells and get you clued up on this innovative form of renewable energy.
What Are Solar Cells?
Solar cells, also known as photovoltaic (PV) cells, are devices that turn sunlight into electrical energy.
They’re made up of semiconductor materials—usually silicon—that produce an electric current when exposed to sunlight.
Although some people call them solar batteries, they don’t store energy like a typical battery.
Instead, they convert energy from sunlight directly into electricity. You can use it for immediate power needs or feed it into your home’s main power supply.
Different Types of Solar Cells
There are two major categories of solar cells, each made from different materials.
The most common type, crystalline silicon cells, is used in over 90% of all photovoltaic installations.
Solar cells made from crystalline silicon (called solar grade silicon) create electricity by absorbing sunlight and converting it into direct current (DC) electricity.
A second major category of photovoltaic cells is thin-film solar cells.
These are typically made using cadmium telluride or copper indium gallium selenide/sulfide; thin-film solar panels account for a small fraction of total PV capacity. However, growth has been significant in recent years.
How are Solar Cells Made?
The creation of a solar cell follows several steps. The first step is to start with silicon.
Pure silicon can be combined with other materials like phosphorous or boron to increase its electrical properties, absorbing more light energy and converting it into electricity.
This process is called doping, and it produces what are known as n-type and p-type semiconductors.
By layering these two types of doped silicon together, each layer becomes an intrinsic part of one larger device that works together to produce electricity from sunlight.
However, another step is required before using your new solar panel – you must coat it with unique material.
This coating is necessary because rainwater would destroy your new device by dissolving the silicon without it.
It also helps protect against oxidation and keeps your panel looking good even after years of use.
Some people choose to add other coatings for extra protection, but most panels only require one coating for added durability.
Finally, you have your functioning solar panel after all those years of hard work (and patience)!
Now, all you need to do is wait for sunny days to plug in some appliances and see if everything worked out okay.
How Do Solar Cells Work?
Your solar panel must have photovoltaic (PV) cells to convert sunlight into electricity.
This type of cell contains layers of semiconducting material that can generate an electric current using light energy from the sun.
When you install a PV system in your home, thousands of these PV cells come together to create energy.
The process is pretty simple and has been around for decades, but it can be challenging to understand what’s happening at a molecular level within each cell—so how do solar cells work? Let’s break it down.
First, let’s start with some basics about our understanding of matter. At its most basic level, matter is made up of atoms.
You might remember learning about atoms when you were younger; as a refresher, atoms are tiny particles that make up everything we see – including our solar panels!
Each atom consists of three parts: protons, neutrons, and electrons. Protons and neutrons form a nucleus in the center of an atom, while electrons orbit around them.
These three components are held together by electromagnetic forces called coulombic attraction.
Coulombic attraction works like gravity, and instead of attracting two objects toward one another, it attracts one object to another object’s charge.
Protons carry positive charges, while electrons carry negative charges. Electrons orbit their nuclei at different distances depending on their energies.
If there are more protons than electrons, there will be a net positive charge and a net negative charge if there are more electrons than protons.
Electrons can move freely between orbits or states based on their energies and surrounding temperatures.
Once you apply heat or light to semiconductors like silicon or germanium (the main ingredients in PV cells), they produce free electrons and holes.
What Are Some Applications of Solar Cells?
The benefits of solar energy extend beyond just saving money on your electric bill.
Homes with a solar power system will usually be eligible for government tax credits and other benefits.
A typical four-kilowatt system is sufficient for some people to meet all their needs, while others opt for larger systems that can generate over 10 kilowatts.
To get an idea of how much power you might need, take an inventory of what appliances and electronics you use throughout your home.
Include things like refrigerators and dishwashers (especially if you have a large family) because these high-powered appliances can deplete your electricity supply quickly.
Once you know how many watts you typically use daily, multiply that number by 30 days to see how many kilowatts you’ll consume in one month.
Then, multiply that number by 12 months to determine your annual consumption.
Keep in mind that most solar panels are rated at about 80% efficiency, so if your panel produces 4 kilowatts per hour during peak sunlight hours.
It should provide roughly 3kW/hrs per day when averaged out 24 hours.
This means it would take approximately 100 days of total sun exposure to recharge your battery system completely.
However, consider that factors such as cloudy weather or excessive shade could slow down or even reverse its progress entirely!
How Efficient Are Solar Cells?
Efficiency is a measure of power output per unit of input. Solar photovoltaic panels typically have an efficiency rating (or rating) between 16% and 25%.
So, to get 1 kWh out of your solar panel, you’ll need about 5 kWh of energy from sunlight. Other electricity sources are more efficient.
For example, coal-fired power plants can generate as much as 43.5% of their energy from coal, while hydropower plants can convert up to 40% of their river flow into electricity.
In other words, despite advances in technology over time – like with computer chips and hard drives – we haven’t gotten any better at turning sunlight into electricity.
How Much Can We Make With Solar Cells?
There is no hard and fast rule for estimating your cost of production.
The most accurate way to estimate costs would be to build a system and see what it costs you, but that’s not feasible when you’re trying to decide whether or not to go ahead with something.
To give you some idea of what your cost might be, here are two sample scenarios:
- You can purchase all of your parts from Amazon or eBay
- You can also find reputable suppliers via Google who sell you only brand-new parts directly from their warehouses.
If you plan to buy secondhand equipment, ask about any warranties or guarantees! If there isn’t one available, ensure you know what condition it’s in before buying it!
When dealing with secondhand equipment, always assume that anything could break at any time without warning and budget accordingly!
Conclusion
How much of a difference will it make in your life if you put solar cells on your roof? In short, not that much.
You won’t be preventing global warming, but you will be saving some money and helping reduce our dependence on foreign oil.
You might even save yourself from power outages during extreme weather like hurricanes and thunderstorms.
Who knows — you may even have fun doing it! After all, what’s better than producing your power right at home?
Please ask us in the comments section below if any other questions are unanswered. We always love hearing from our readers!
