How many solar panels for a 5kW system in South Africa?

How many solar panels for a 5kw system

In South Africa, a 5kW solar system typically includes 13-17 solar panels and requires approximately 25-36 square meters of roof space, depending on the panels’ wattage and tilt angle. Solar panel dimensions vary by brand and their intended use (commercial or residential), but most often, panels used in a 5kW system measure about 1.7 meters by 1 meter.

If you’re installing solar, see our quick calculation guide below for a step-by-step and simple approach to this calculation for home solar systems.

Key takeaways

  • The number of solar panels for a 5kW system depends on factors like panel type, efficiency, available space, and roof suitability.
  • Consider using a solar panel calculator to estimate the number of panels needed based on your power consumption and sun exposure.
  • When choosing panels, balance cost and efficiency based on your budget and energy goals.
  • Ensure compatibility with your inverter and plan for future expansion, if desired.
  • Assess your roof’s suitability, considering factors like direction, material, shade coverage, and structural support.

How to calculate how many panels you need

Determining how many solar panels you’ll need to achieve a 5kW solar system can be done with a simple approach. Here’s a step-by-step guide:

1. What panel type are you using?

  • Monocrystalline panels – More efficient with higher wattage output, typically ranging between 310 and 400 watts.
  • Polycrystalline Panels – Less efficient but more affordable, with wattage output generally between 250 and 300 watts.

2. Calculate the panels needed

  • Here’s the Monocrystalline Calculation:
    • With an average wattage output of 400W per panel, divide 5,000W (5kW system) by 400W.
    • This results in approximately 13 panels needed (5,000W / 400W = 12.5, rounded up to 13).
  • Polycrystalline Calculation:
    • For polycrystalline panels averaging 300W per panel, divide 5,000W by 300W.
    • This results in about 17 panels needed (5,000W / 300W = 16.6, rounded up to 17).

3. Estimate the roof space required

Solar panels used in grid-tied systems typically come in two standard sizes based on the number of solar cells they contain. Panels with 60 cells generally measure around 1.6 meters in height and 1 meter in width, while those with 72 cells are approximately 2 meters tall and 1 meter wide. Let’s use the 1.6m x 1m panel for our calculation below.

  • Monocrystalline
    • Each panel requires about 1.7 square meters of roof space, so for 13 panels, you’ll need approximately 27.6 square meters of roof space, including a 25% safety margin.
  • Polycrystalline
    • With 17 panels, each requiring 1.7 square meters, you would need roughly 36.1 square meters of roof space, including a 25% safety margin.

Solar panels: Fundamentals

Solar panels are crucial in catching the sun’s rays and turning them into power. It’s key to know how solar panels work, especially if you’re new to solar energy.

The word you should understand is photovoltaic. It talks about turning sunlight into electricity straight on. Inside solar panels are photovoltaic cells that make this change happen.

Think of an array as several solar panels set up together. The pattern in which panels are connected affects how well they work together.

In an array, we can link solar panels in different ways. For instance, a string is connecting panels one after the other in series. This must keep the voltage at a safe level for the system. Doing this helps make the solar panel system work better.

Another way to connect is parallel. Here, panels are set side by side. This makes the total current increase, boosting the system’s power output.

The Maximum Power Point Tracker (MPPT) is crucial in solar panel setups. MPPT watches the panel array’s voltage. It then adjusts things to make sure the system works as well as it can.

Knowing about photovoltaic, how to set up an array, and use MPPT is key for getting the most energy from solar panels.

Advantages of understanding solar panel fundamentals

Understanding solar panels’ basics brings several benefits:

  • It helps with designing systems well. Knowledge of how arrays, strings, and parallels work makes our solar systems more efficient.
  • It aids in smart choices. Knowing about how photovoltaic systems work helps us pick the best solar panels and parts.
  • It’s good for fixing things. Knowing the basics lets us find and solve any issues with our solar systems, making them last longer.

Learning the basics about solar panels makes us smart users. We can pick the best, solve any problems, and keep our solar systems running well for longer.

How do solar panels work?

Solar panels use sunlight to create electricity. They work by moving electrons with the sun’s help. This process, known as the photovoltaic effect, is essential for solar power generation.

In a solar panel, there are layers called N-Type and P-Type. The N-Type layer has too many electrons, and the P-Type has too few. Sunlight provides energy, making the electrons move. This movement creates an electric current.

Silicon is the key material in making solar panels. It’s a semiconductor that’s great for moving electrons. By processing silicon, we create cells, which are then made into solar panels.

“Solar panels work by harnessing the movement of electrons in response to sunlight. This process occurs in the N-Type and P-Type layers of the solar panel’s molecular structure.”

There are two main types of solar cells: monocrystalline and polycrystalline. Monocrystalline cells are from a single crystal. They look the same and are very efficient. Polycrystalline cells come from many crystals. They’re a bit less efficient but more affordable.

Monocrystalline and Polycrystalline Solar Panels

The process of generating electricity

Flowing electrons in the solar panel create electricity. This power runs devices or charges batteries. Solar panels make more electricity in strong sunlight and with bigger, more efficient surfaces.

In conclusion, solar panels turn sunlight into power through the movement of electrons. This power can be used for homes, businesses, and devices. Choosing between monocrystalline and polycrystalline depends on what’s more important to you – efficiency or cost.

Monocrystalline vs Polycrystalline solar panels

When picking between monocrystalline and polycrystalline solar panels, you’ve got a lot to think about. Both types have good points and bad points, so it’s vital to look into what you need and like.


Monocrystalline panels have an edge in efficiency. They’re made from a single crystal, which means they turn sunlight into power better. They need less space than polycrystalline panels to produce the same power amount.

Polycrystalline panels, however, are built from many silicon crystals. They’re not as efficient as monocrystalline ones but still do well. Plus, being cheaper, they’re a good pick for anyone watching their budget.


Cost matters a lot when choosing solar panels too. Monocrystalline panels are pricier because they’re more efficient and made using a complex process. Yet, prices vary based on the brand, where you buy them, and if there are any deals.

Polycrystalline panels cost less, making them affordable for many. So, if you’re looking at solar panels mainly from a cost angle, polycrystalline might be your best bet.


The way manufacturers make monocrystalline and polycrystalline panels is different. Monocrystalline panels’ single crystal structure makes them harder to make, increasing their price.

Polycrystalline panels come from many silicon crystals, which is easier and cheaper to do. But this makes them a bit less efficient.


Choosing between the two also depends on how you plan to use them. For small spaces, monocrystalline panels work best because of their high efficiency. They produce a lot of power in a limited area.

If you have a lot of space, polycrystalline panels could be what you need. They’re a good choice for big projects where space isn’t an issue.

Your final choice should fit your budget, space availability, and plans. Think about what your power needs are, where you’re located, and your financial situation. This will help you choose the right type for you.

Solar panels sizing

When deciding on a solar panel system, think about your needs and space. These two things are very important.

Your needs are key in picking the right system size. Think about how much electricity you use, and your power goals. Do you want to lower your energy bill or be fully off-grid? Knowing this helps decide how many panels you need.

Space is another big point to consider. If your roof is small, you might choose high power panels, like 400W ones, for more output. But if space is not an issue, using more smaller panels could be better.

Recent years have seen the growth of solar panel technology. This means larger panels with more power are now available. So, you can produce more energy from a smaller area.

Think about your current system’s voltage when adding more panels. Choosing panels that match your system avoids problems.

It’s often best to go for the biggest panels your system can handle. This gives you more power and lets you add more later. Planning to expand within a year can mean getting the same type of panel again.

Getting the right size system is key to meeting your energy goals. Look at your needs, the space you have, how panel sizes have changed, and if the panels will work with your current system.

“Picking the right system size is crucial for its efficiency and performance. Look at your energy use and available space to figure out how many and what size panels you need.”

Is your roof suitable for solar panels?

Deciding if your roof can have solar panels means looking at several things. We’ll check important points to see if solar panels are a good fit for your roof.

Complex roofs

Complex roofs need special care before installing solar panels. They might have extra parts or angles. This can increase the work needed and possibly the cost. A professional can check and suggest the best way to install them.

Roof direction

The direction your roof faces matters a lot for solar panels. South-facing roofs get most sunlight all day. This makes them best for energy production. Roofs facing east or west can also work, but they might produce a bit less. Roofs facing north often get too little sun to work well.

Roof material

Your roof’s material can change how solar panels are installed. Each material has its own needs. For example, thatched roofs need special safety mounts. Flat roofs might need things to tilt the panels for more sun. A professional can handle these differences.

Shade coverage

Too much shade on your roof can make solar panels less effective. Shade from trees, buildings, or other things cuts down on sunlight. Before installing panels, removing as much shade as possible is a good idea for better results.

Roof age and support

Your roof’s age and how strong it is are vital for solar panels. You need to make sure your roof can carry the extra weight for many years. If your roof is old, it may need checks or fixes before you start with the panels.

Thinking about these points helps you see if your roof can have solar panels. It’s smart to get advice from experts in solar energy. They can give the best advice for your situation and aims.

Ready for solar panels in South Africa? Take a look at this guide for 5kW solar systems. It offers insights on what you need, how to install, and the design to get the most of solar power. It will help you choose wisely.


Deciding how many solar panels to get for a 5kW system in South Africa is complex. You need to think about panel types, how much space you have, and if your roof is right. This helps you to choose the best solution for your energy needs.

Buying solar panels is a wise and sustainable move. Pick panels that are high quality and match your energy needs. Installing them is good for the planet, cuts down on old energy use, and fights against climate change.

To get the most from your solar panels, choose wisely. Think about the kind of panel, how well it works, and how long it lasts. Go for top brands and trusted sellers to get panels that work well and last a long time. By using solar technology, you’ll help the environment, save money on power, and make South Africa greener.

FAQ: How many panels are needed for a 5kW system?

How do I determine the number of solar panels needed for a 5kW system in South Africa?

To calculate the number of solar panels for a 5kW system, you must look at various factors. This includes the panel type, roof space, and how much sunlight your area gets. Think about how much power you use and your energy goals. Then, you can find the right amount of panels. See our calculation guide at the top of this article.

What are the fundamentals of solar panels?

Solar panels turn sunlight into electricity. This process is called photovoltaic. A group of solar panels is called an array. Strings are sets of panels with the same voltage. Connecting panels in parallel boosts amperage. MPPT helps get the most power by adjusting the voltage.

How do solar panels work?

Solar panels use sunlight to move electrons. These create an electric current. The cells in solar panels, usually made of silicon, do this work. They’re made in a special way to be efficient.

What is the difference between monocrystalline and polycrystalline solar panels?

Monocrystalline panels are more efficient and cost more. Polycrystalline panels are cheaper but less efficient. Your choice depends on your budget and space.

How do I determine the size of my solar panel system?

Choose your solar panel system size based on your needs and space available. If space is tight, go for higher power panels. But, with room for more, you can use several smaller ones. Make sure to pick panels that can grow with your system. Also, consider the inverter’s maximum size and future upgrades within a year.

Is my roof suitable for solar panels?

Finding out if your roof can support solar panels considers many things. Ensure your roof is not too complex and can capture enough sunlight. Different roofs need special attention, like fire risks or structure needs. Keep your roof as clear from shade as possible for good solar energy. Also, ensure your roof is strong enough to hold solar panels.

Source Links



Please enter your comment!
Please enter your name here