Solar Energy Panels

Renewable and Sustainable Energy with Solar Panels

Skill Level
20 Min

Chapter 2

Table of Contents

Solar Panels

We are a remarkable species. We have made many rapid advancements and innovations in technology that show our brilliance.

This chapter will discuss one such innovation- the solar panel, and all there is to know about it. Are you a techie enthusiast and want to learn what we’ve achieved in solar technology? This is for you.

What Are Solar Panels?

solar panels

By now, you must be well acquainted with what solar energy is and how to harness it to power your home or workplace. Solar panels are a part of the solar energy systems to harness the sun’s energy.

In simple terms, solar panels or PV modules are large sheets of glass that capture the sun’s energy and convert it into electricity. You then use the power in your house or workspace.

Do I Need Solar Panel System for My Home or Office?

Solar energy has many advantages. You might be wondering whether you should buy solar panels. Is it worth it?

Well, wonder no more! Below we have listed some of the most important reasons and factors you need to consider before installing solar power. Read through to make the right decision.

i. Your Location

The primary factor in making the decision is your location. It is one of the crucial elements in determining whether solar panels are the right choice for you or not.

Let’s start with the basics. Solar panels need the sun’s energy to work. Hence, your home must be located in a place where it can easily do that. Tall buildings, trees, and other obstructions which block sunlight will stop your PV modules from operating at full potential. The ideal locations are exposed directly to the sun’s rays, without barriers between places in the south.

Along with your location, you should also consider the climate where you live. If it is always cloudy near your residence, then the solar panels won’t operate optimally. You may need to install a storage system to meet your electricity needs.

Consult your solar panel provider and ask them to assess your neighborhood to know whether solar energy is the right choice for you.

ii. Your Roof

The next thing to check is the roof orientation and angle. PV modules are considerably heavy, with a weight of around 20 kilograms. Furthermore, they have an immensely long life span as well. Most solar panels will probably last longer than your roof!

Have a professional inspect your roof to determine whether it is suitable for solar installation. You need to be sure that your roof materials are strong enough to handle the solar panels’ weight for a considerably long period.

It will also be in your best interests to ensure that your roof is open to the sky. You should install the panels at an angle that allows maximum exposure to sunlight.

iii. Your Weekly or Monthly Electricity Usage

Once you have determined that your home’s location is fit for solar panel installation, you need to consider your electricity needs.

You should find out your overall electricity consumption rate to know how many solar panels to install.

Once again, it is better to call professionals to do this for you. They will look at your past electricity bills, the total number of appliances in your house, and other factors in determining the right amount and kind of solar panels for your residential or commercial building.

Always install a few more modules to act as buffers in cases of emergencies.

iv. Cost Savings

solar savings

The entire purpose of installing PV modules in your home is to save money. This is why you need to do a cost-benefit analysis. Solar panels cost approximately $10,000 – $20,000.

It takes a couple of years for solar savings to outweigh the costs incurred in the purchase and installment. Therefore, ask yourself if you plan to live in your current residence for the next few years, at the very least.

What Are Solar Panels Made Of?

Brace yourself because it is time to get a bit technical. But don’t worry, we won’t get too technical. Just enough to educate you on what makes a solar panel so that you’re entirely aware of its components.

The most common solar panels are crystalline types that look like large blue or black rectangles. They are made of the following elements or parts:

Solar Cells

At the core, solar modules have many individual units called solar cells. Solar cells are made up of silicon. Since silicon is found in abundance, we don’t have to worry about the construction of solar panels depleting its supply.

Connectors or Conductors

The next components that work in synergy with the solar cells are connectors or conductors in the solar panel. These are usually made up of silver since it is an excellent conductor.

Back Sheet

Moving further, you have the back sheet, which is a material that is resistant to electricity. Its purpose is to prevent water and sand from entering the gadgets’ working parts and clogging them up.

Ethylene Vinyl Acetate

All of these components are bound to each other by two layers of EVA (ethylene-vinyl acetate). This material serves the purpose of an adhesive, keeping all the respective parts joined together and protecting them from dirt and water.


There is a thin glass coating at the very top, which safeguards the solar cells located underneath it. Simultaneously, it allows all the sunlight to fall on them for conversion to electricity.


The last part of a solar panel is its frame, usually composed of aluminum. This gives the solar panel its structure and makes installation easy.

How Long Do Solar Panels Last?

Suppose the information presented so far about Solar Panels has been successful in convincing you to buy one. You now have one last pressing question left: How durable is it? How long does it last? And lastly, how does solar panel quality change over the years?

There is good news for you. Solar panels have incredibly high durability, and their standard of performance also boasts a high consistency. What does this entail in practical terms? Read on to find out.

Solar Panel's Lifespan


Although the industry standard established by manufacturers states a period of 25-30 years for a Solar Panel’s life, the latest models available on the market have considerably higher lifespans of up to 40 years.

But what does it mean when we say that solar panels have a lifetime of 30 years? Does that mean that after that specified period, they stop working? The answer is no. This means that in 30 years, the PV modules will no longer be producing the optimal amount of energy.

All Solar panels experience deterioration in their electricity-producing capacity at a steady rate. But this is not a cause for worry.

Deterioration of the Solar Panel

A study conducted by the National Renewable Energy Laboratory found that solar panels will experience a mean deterioration rate of 0.5% per annum. According to this rate, a solar panel with a 25-year lifespan will still operate at around 89% efficiency, even after 25 years. That’ll certainly help you cover your investment cost on the panels and reap other benefits.

Types of Solar Panels

A Solar panel’s function is to takes in sunlight and transforms it into electricity. Solar panels come in a wide variety of forms, shapes, quality, and prices. We have mentioned some of the most popular PV module classes and their functions if you’re wondering which one would be best for you.

Solar panels can be categorized according to junctions and generations. There are single and multi-junction panels with a focus on the number of layers. The first, second, or third generations refer to a solar panel’s quality and components.

1st Generation PV Modules

There are two kinds of 1st generation solar panels. They’re both available in the market. However, they both have different price ranges and qualities that we’ve explored below.

A. Monocrystalline Solar Panels

monocrystalline solar panels

As the name suggests, these solar modules are made of crystalline silicon. They are easily identifiable and distinguishable because of the dark appearance and smooth edges.

Since silicon is one of the purest elements available, these solar panels have high efficiency and power output. It also occupies the least amount of space and has the most excellent durability. Lastly, it is also the best in resistance to high temperatures.

Due to such high quality, monocrystalline solar panels are also the most expensive.

B. Polycrystalline Solar Panels

Another 1st generation solar panel is polycrystalline. It has similar attributes to monocrystalline. One difference is that it is made up of melted silicon, which is a process that is cheaper and less time-consuming.

Due to this, the polycrystalline solar panels are slightly lower in power potential and effectiveness in comparison to the monocrystalline model. It also doesn’t last as long and occupies more significant space.

However, the difference in quality is not significant. If you are looking for a high-efficiency solar panel, you should indeed consider this one.

2nd Generation PV Modules

The 2nd generation solar panels are a lower version of the first. These are made of solar cells and are used in buildings and apartments.

A. Thin–Film Solar Cells

These solar panels are a much cheaper option. They are easily available due to the less material needed for manufacture.

They have two significant advantages for the users. The first advantage is resistance to exceptionally high temperatures and flexibility; therefore, you can use them for different purposes.

They also have a share of disadvantages, one of them being installation difficulty. Thin-Film solar panels are enormous, making installation tedious. They are rarely used in residential locations. They also come with a shorter warranty and lesser lifespans.

B. Amorphous Silicon Solar Cell

The most significant advantage these solar modules have is portability because they are tiny. Solar-powered batteries, watches, and calculators all function by amorphous silicon solar cells. They use a triple-layered technology.

Amorphous silicon solar panels have low efficiency, especially in comparison to crystalline silicon. However, they are available at relatively lower prices.

3rd Generation PV Modules

Thin film solar panels

Most third-generation solar panels are still under development. Most use organic materials for functioning.

A. Biohybrid Solar Panel

This is a solar panel that is still in its prototype stage. Biohybrid solar modules use photosynthesis to generate energy. The difference is that it dramatically magnifies the magnitude of the process. Thereby increasing efficiency by a thousand times more than the 1st generation solar panels.

B. Cadmium Telluride Solar Panel

It requires the least amount of water to produce a higher quantity of energy at a lower price. However, a significant disadvantage is the health hazard it creates. The solar panels create toxic substances, causing considerable damage if inhaled. This is the reason most people still avoid them.

Solar Panel Sizes

Now that you’re aware of the different generations and types of solar panels let’s look at the size options.

Knowing the different solar panel sizes is essential in selecting the most suitable for your rooftop or any other installation.

Standard Solar Panel Sizes

There are three standard solar panel sizes. They include the following:

  • 72-cell panels have a length of 77 inches and a width of 39 inches.
  • 60-cell panels have a length of 66 inches and a width of 39 inches.
  • 96-cell panels have a length of 62.6 inches and a width of 41.5 inches.

Most residential homes use small-celled panels, which are more feasible.

Solar Panel Frame Thickness

The solar panels’ thickness ranges from 1.4 to around 1.9 inches. You can decide which thickness suits your roof size before picking on a panel.


The last thing to consider when buying a solar panel for installation on your roof is its weight.
  • 60-cell panels weigh 18 kilograms.
  • 72-cell panels weigh around 23 kilograms.

Make sure you consult professionals in determining whether your rooftop can bear the weight of the solar panels you want to install.

How Efficient Are The Solar Panels?

The solar panels’ ability to transform received sunlight into electricity determines efficiency. Therefore, if you have two PV modules that receive the same sun intensity for the same duration, the one with the higher efficiency will produce more electricity.

On average, most Solar Panels have an efficiency between 15%-20%. However, the efficiency of each panel depends on the type of solar panel that you’re using.

As mentioned before, the most common types of solar panels are:

Monocrystalline Solar Panel Efficiency

These have the highest efficiency of around 27% because they are made from the purest form of silicone. If you want to get the maximum benefit from your solar panels, you should go for the monocrystalline solar panels.

They’re more commonly used in office spaces where more power is required.

Polycrystalline Solar Panel Efficiency

They are slightly less efficient than monocrystalline solar panels because they are made from less superior material. Thus, their efficiency decreases to around 22%. 

However, you can use them in your homes if you don’t have high power consumption.

Thin-Film Solar Panel Efficiency

They are as efficient as polycrystalline solar panels, although their durability may be less. Still, they make an excellent choice for homes and residential areas.

How to Measure the Efficiency of Solar Panels

Solar panel system

If you want to calculate the efficiency of your solar panels, follow these simple steps.

Step 1#: Find Maximum Output

The first step is to find out your solar panel’s maximum power output.

Don’t worry; this is easy. Your solar panel’s maximum power output is displayed on the information sheet that comes with it. You can also find it by looking at the sticker at the back of the panels.

Step #2: Determine Length & Width

The next step is to determine your solar panel’s length and width. You can do this two ways.

Either take a measuring tape to determine the lengths. You can also find your device’s specification sheet and read the length and width measurements written there.

Step #3: Find Optimum Power Output per Unit Area

The third step is determining the maximum power output per unit area. This is a bit tricky, but we will guide you step by step. 

First, use the measurements that you have taken to determine your solar panel’s area. Since most solar panels have a negligible thickness, it is okay to ignore it and multiply the length and width.

Next, divide your solar panel’s total power output with its area to determine the maximum power output per unit area.

Step #4: Determine the Irradiance Value

The next step is to determine the irradiance value at STC.
Step 4 requires you to know the irradiance value of your solar panel. This refers to the amount of radiation that falls on your device. STC means Surface Test Conditions. These are a set of criteria that need to be fulfilled during device testing. STC includes:
  • A solar cell temperature of 25 degrees Celsius.
  • An air mass of 1.5 units.

Note: Under NTC, the solar irradiance level is 1000 watts per square meter.

Step #5: Calculate the Efficiency

In this step, you’re supposed to calculate the efficiency of the panel. Sit tight because you’re almost there! There is just one step left.
Divide the maximum power output per unit area by the solar irradiance level obtained in the previous step.
And there you have it! The answer you get is the efficiency of your solar panel. Multiply by 100 to change it into percentage form.

What Factors Affect Solar Panels' Efficiency?

Most solar panels have a fixed range within which they work optimally. However, certain factors may affect this efficiency. These factors include:


Even a small amount of shade can drastically lower the efficiency of your solar panel. Always consult with an expert before installing your solar panel to know the best installation position.

Roof Position

The angle of your roof also determines how much energy your solar panel system can harness throughout the day. The optimal angle for most locations is 30-48 degrees.


solar panel maintenance

Make sure your solar panels are regularly inspected and cleaned. Accumulated dust particles and other materials may lower its performance.


Although the more sunlight your solar panel is exposed to, the better it is, the same doesn’t hold for temperature. Extremely high temperatures damage solar panels and reduce efficiency.

Reasons to Get Solar Panels

We saved the best bit to the end. A lot of people wonder why they should suffer through the hassle of purchasing and installing PV modules. Are they worth it? The answer is yes. Below, we have highlighted why solar panels are the future and why you should invest in them.

i. Green and Clean Energy

Unlike fossil fuels, which are harmful to the environment, solar panels are entirely pollution-free. They produce no toxic gases, do not deplete any natural resources.

With solar modules, you reduce your carbon footprint and take your first step towards a sustainable future.

ii. Help You Achieve Electrical Independence

Traditional forms of energy require fossil fuels. The problem with fossil fuels is that they are non-renewable resources. The conventional electricity prices keep fluctuating.

Solar panels will free you of this worry. You no longer need to fret about unprecedented increases in fuel prices. You can enjoy electricity at a modest, constant rate throughout your life. In essence, solar panels give you independence from the utility company.

iii. More Efficient and Have Better Control

If you use conventional electricity, then you’re probably aware of how it reaches your house. Extended and convoluted wires carry it over distances to get to your appliances. Such a complicated process means that power losses and load shedding is a guarantee.

This is where solar panels come in. Situated directly on your roof, they operate at a much higher frequency and allow you to control your power consumption and electricity bill. Furthermore, you don’t have to worry about power interruptions, especially on rainy days.

iv. Crucial To Economic Growth

This reason isn’t directly applicable to you, but it does benefit your country. Solar panels boost economic growth and create employment opportunities. As more people drift towards the industry, corporations and multinationals will be compelled to install them.

v. The Sun Is Free and Available to Everyone

You can’t put a price tag on the sun. A solar panel becomes financially beneficial from the moment it is installed, but these savings will only become visible and significant in the long run. So don’t waste any more time; get your first solar panel system installed now!

vi. You Can Sell Excess Energy for Profit


A solar panel can create excess energy during the day, sometimes much more than your consumption. This gives you an option to supply the extra power to the community through net-metering.

You can do this for free, or you charge a price if you’re interested in making a few bucks on the side for yourself.

vii. You Can Make Your Barren Land Productive

Solar panels are a great way to make use of vast stretches of barren, unutilized land. You can create an entire field of solar panels that absorb the sunlight during the day, and you can then store the electricity to supply to your consumers.

viii. Solar Panels Are Durable

PV modules have high durability. They are resistant to wind, rain, sand, and any other forms of erosive materials. This is because they are coated in several layers of durable glass, which protects the device.

Solar panels also last for decades, well beyond their warranty periods. As explained above, the warranty period is just a marker beyond which the panel operates at a slightly sub-optimal efficiency level.

ix. Adds Value to Your Home

Since solar panels are a rising technology set to become dominant in the future, installing them in your home will considerably raise its value.

Anyone looking to purchase your property gives careful consideration to the electricity costs they will have to bear. Since solar panels reduce these costs significantly, your home will be worth more with solar modules.

x. Usable in the Dark

Solar panels operate in the dark and with just as much efficiency. You can install solar batteries that act as electricity reserves, storing all the electricity harnessed during the day. You can use this power whenever you desire, regardless of whether the sun is out or not.

How Much Power Can I Generate With Solar Panels?

A typical solar panel produces an average of 265 watts in a single day. However, this figure can drop down to 220 watts and even go as high as 360 watts. Different companies have different solar panel outputs depending on multiple factors.

Multiply your solar panel’s power by the number of hours of sun it receives every day to get the output. This will give you an idea of how much electricity it can harness.

In even simpler terms, try to remember that a solar panel of around 4 kilowatts can run a home containing an average of four to five individuals. A solar panel with comparatively lesser power, such as 2 kilowatts, can supply electricity to a relatively smaller home.

If you find it difficult to calculate how much power you need, it is helpful to know that a three-bedroom house consumes around 2700-3000 kilowatts of energy per annum.

There are certain factors you can alter to increase solar panel efficiency. This includes changing its angle and removing any obstructions.

Remember that seasonal variations also account for the changes in the amount of power your system harnesses.

Where Can I Buy Solar Panels?


Are you convinced yet? We certainly hope so! Let us round up this chapter now by comparing some of the best places you can purchase solar panels for your home.

A. Wholesalers

The most significant advantage of buying from wholesalers is that the price is lower than other outlets. The entire purchasing process is quick and straightforward.

However, remember that wholesalers don’t install solar panels for you. You have to do that or hire an installer. Therefore, if you lack the proper technical knowledge and expertise, it is better to avoid them and consider purchasing from other places.

B. Amazon

This is similar to wholesale, in the sense that you need to do the installation yourself. Furthermore, Amazon sells solar panels in kits, you should make sure the package you are purchasing has all the specified components.

One last point to note is that solar panels on Amazon probably won’t be sufficient to power your home. Order from the platform if you need them for other usages, such as motor vehicles or boats.

C. Installation Companies

This is probably your best bet if you’re a newbie when it comes to solar panels. The company does all the work for you.

They carry with them the assurance of experience and the guarantee of quality. The solar installers do the entire setup process and check to see if everything is working correctly.

Installation companies also offer leases and other power-sharing options.
We hope you found this chapter satisfactory. Now you have everything you should know when buying a solar panel system—best of luck with your electricity-saving journey in the future.
The inventor of solar energy was a genius.