What is Solar Panel?
A solar cell panel, solar electric panel, photo-voltaic (PV) panel, or just a solar panel is an assembly of photovoltaic cells mounted in a framework for installation. Solar panels are used to convert light from the sun, which is composed of particles of energy called “photons”, into electricity that can be used to power electrical loads.
A collection of PV modules is called a PV panel, and a system of PV panels is called an array. Arrays of a photovoltaic system supply solar electricity to electrical equipment.
Solar panels can be used for a wide variety of applications including remote power systems for cabins, telecommunications equipment, remote sensing, and of course for the production of electricity by residential and commercial solar electric systems.
On this page, we will discuss the history, technology, and benefits of solar panels. We will learn how solar panels work, how they are made, and how they create electricity.
A Short History of Solar Panels
The development of solar energy goes back more than 100 years. In the early days, solar energy was used primarily for the production of steam which could then be used to drive machinery.
But it wasn’t until the discovery of the “photovoltaic effect” by Edmond Becquerel that would allow the conversion of sunlight to solar electric energy was.
Becquerel’s discovery then led to the invention in 1893 by Charles Fritts of the first genuine solar cell which was formed by coating sheets of selenium with a thin layer of gold. And from this humble beginning would arise the device we know today as the solar panel.
Russel Ohl, an American inventor on the payroll of Bell Laboratories, patented the world’s first silicon solar cell in 1941. Ohl’s invention led to the production of the first solar panel in 1954 by the same company.
Solar panels found their first mainstream use in space satellites. For most people, the first solar panel in their life was probably embedded in their new calculator – circa the 1970s!
Today, solar panels and complete solar panel systems are used to power a wide variety of applications. Yes, solar panels in the form of solar cells are still being used in calculators.
However, they are also being used to provide solar power to entire homes and commercial buildings, such as Google’s headquarters in California.
How do solar panels work?
Simply put, a solar panel works by allowing photons, or particles of light, to knock electrons free from atoms, generating a flow of electricity. Solar panels actually comprise many, smaller units called photovoltaic cells. (Photovoltaic simply means they convert sunlight into electricity.) Many cells linked together make up a solar panel.
Each photovoltaic cell is basically a sandwich made up of two slices of semi-conducting material, usually silicon the same stuff used in microelectronics.
To work, photovoltaic cells need to establish an electric field. Much like a magnetic field, which occurs due to opposite poles, an electric field occurs when opposite charges are separated.
To get this field, manufacturers “dope” silicon with other materials, giving each slice of the sandwich a positive or negative electrical charge.
Specifically, the seed phosphorous into the top layer of silicon, adds extra electrons, with a negative charge, to that layer. Meanwhile, the bottom layer gets a dose of boron, which results in fewer electrons, or a positive charge.
This all adds up to an electric field at the junction between the silicon layers. Then, when a photon of sunlight knocks an electron free, the electric field will push that electron out of the silicon junction.
A couple of other components of the cell turn these electrons into usable power. Metal conductive plates on the sides of the cell collect the electrons and transfer them to wires. At that point, the electrons can flow like any other source of electricity.
Recently, researchers have produced ultrathin, flexible solar cells that are only 1.3 microns thick about 1/100th the width of a human hair and 20 times lighter than a sheet of office paper.
There are other types of solar power technology, including solar thermal and concentrated solar power (CSP) which operate in a different fashion than photovoltaic solar panels, but all harness the power of sunlight to either create electricity or heat water or air.
Types of Solar Panel
There are three major types of solar panels: monocrystalline, polycrystalline, and thin-film.
Each type has its own unique advantages and disadvantages, and the solar panel type best suited for your installation will depend on factors specific to your own property and desired system characteristics.
1. Monocrystalline Solar Panel
These solar panels are made using thin wafers of silicon, which are extracted from artificially grown crystals. Single crystals developed in isolation help to form these cells and make them the most efficient.
This is why these are the most expensive among the other types. Compared to their counterpart polycrystalline cells, monocrystalline solar cells are about 35% more expensive and provide an efficiency rate between 15–24%.
2. Polycrystalline Solar Panel
Polycrystalline solar panels are a newer development in the different types of solar panels, but they are rising quickly in popularity and efficiency. Just like monocrystalline solar panels, polycrystalline cells are made from silicon. But polycrystalline cells are made from fragments of the silicon crystal melted together.
During the manufacturing process, the silicon crystal is placed in a vat of molten silicon. Instead of pulling it out slowly, this crystal is allowed to fragment and then cool.
Then once the new crystal is cooled in its mold, the fragmented silicon is thinly sliced into polycrystalline solar wafers. These wafers are assembled together to form a polycrystalline panel.
Polycrystalline cells are blue in color because of the way sunlight reflects on the crystals. Sunlight reflects off of silicon fragments differently than it does with a pure silicon cell.
Usually, the back frames and frames are silver with polycrystalline, but there can be variations. The shape of the cell is square, and there are no gaps between the corners of the cells.
3. Thin-film solar panel
If you’re looking for a more cost-effective option, consider thin films. Thin-film solar modules are made by placing one or more films of photovoltaic material (such as silicon, cadmium or copper) on a substrate.
These types of solar modules are the easiest to manufacture and, due to economies of scale, cheaper than the alternatives, as less material is required to manufacture them.
They are also flexible, which opens up many possibilities for alternative applications and is less affected by high temperatures. The main problem is that they take up a lot of space and are generally unsuitable for residential installations.
In addition, they offer the shortest guarantees, as their lifespan is shorter than that of mono- and polycrystalline solar modules. However, they can be a good option to choose between the different types of solar panels that have plenty of space.
4. Amorphous Solar Panel
The cheapest form of solar cell is an amorphous solar cell. These are newly launched cells that are manufactured in a unique way. They avoid the use of crystals. Instead, their production process involves thin silicon deposits on the backing substrate.
Amorphous solar cells provide two major benefits, ie. Flexibility in solar cells with its extremely thin silicon layer, and high efficiency in low levels of light during winter.
But, while these promise the above benefits, they also compromise efficiency. They provide the lowest efficiency rates of 7% – 9% compared to the other two variants. Thus, they require about twice the panel area to give the same output.
Until now, they do not even have an approved production technology in the industry, and therefore, they are less robust than the other two types of solar panels.
5. Biohybrid Solar Panel
It is not a completely solar cell, but a hybrid solar cell is a mixture of monocrystalline solar cells and amorphous solar cells. Hybrid solar cells are called HET (heterojunction with intrinsic thin layer) solar cells.
Compared to each individual type of solar cell, the hybrid type is the most efficient due to the combination of the power of the two solar cells. These work best during sunny seasons, ie beyond the 250C temperature. In view of the same, this helps generate about 10% more electricity.
If one has to choose the best, polycrystalline cells prove to be the most suitable for most installations due to their value for money, design, and efficiency rate.
Solar panels can last more than 25 years. Many solar panels installed as early as the 1980s are still working at the expected capacity. Solar panel longevity has increased dramatically over the past 20 years. While the industry-standard service life is around 25 to 30 years, a solar panel loses about 0.8% of its output every year.
The average cost of solar panels in 2023 is around $1 to $1.50 per watt for the most energy-efficient monocrystalline solar panels1, $15,000 to $20,000 for a typical 5 kW system2, and $2.95 per watt on a cost per watt basis before incentives. The cost can also be affected by government incentives and tax credits.
How to Build a Solar Panel
Step 1: Create a Template & Putting the Frame Together.
Step 2: Assembling the Solar Cells.
Step 3: Creating Holes for My Connections.
Step 4: Gluing the Solar Cells Down.
Step 5: Soldering Bus Wire.
Step 6: Visiting the Electric Side.
Step 7: Adding Even Pressure on the Plexiglass.
Step 8: Installing the Junction Box
When the sun shines onto a solar panel, energy from the sunlight is absorbed by the PV cells in the panel. This energy creates electrical charges that move in response to an internal electrical field in the cell, causing electricity to flow.
Most residential solar panels on today’s market are rated to produce between 250 and 400 watts each per hour. Domestic solar panel systems typically have a capacity of between 1 kW and 4 kW.