Introduction
The best-known part of a solar power system is the Solar Panels.
Solar energy is probably the most popular renewable energy in the world today.
The solar power industry is ever-growing, and as always, new technology is being produced all the time .
This guide will help you understand how solar panels work, how they function as part of a solar power system and which panels would best suit your needs .
Content
Fundamentals
How Do They Work?
Monocrystalline vs Polycrystalline
Solar Panel Sizing
Which Brands Are Best?
Is Your Roof Suitable?
Let’s Talk Cost
How The Panel Fits In With A System
FAQCHAPTER 1
Fundamentals
This section will include phrases or words that you may not know if you are a beginner in the market like:
- Photovoltaic
- Array
- String
- Parallel
- MPPT
Are You A Beginner?
As always, we’ll start off with the fundamentals.
If you’re not new to our guides and know the jargon used in the solar industry, you may want to scroll past this section.
The word ‘photovoltaic’ is made up of two words. The Greek word ‘phōs’ means ‘light’ and ‘volt’, the electromotive force unit.
The definition of photovoltaic means to produce energy from the sun.
Photovoltaic Array refers to your solar panel setup.
A group of solar panels whose combined voltage does not exceed the maximum MPPT range.
This way of connecting solar panels increases the amps.
An MPPT (Maximum Power Point Tracking) tracks the voltage coming from the PV array and maximises the energy produced by the array.
If you have any questions that have not been covered in this article, you can always contact us.
CHAPTER 2
How Do Solar Panels Work?
To understand how solar panels work, you need to look at the molecular structure of the N-Type & P-Type layers.
I don’t want to bore you with the details so, I’ll give you a basic rundown on how they work below.
Moving Electrons
Photons from sunlight cause free electrons to move through a circuit by forcing the electrons from their bonds in the N-Type layer to fill voids in the P-Type layer, generating electricity.
What are Solar Panels Made from?
Solar panels are made of different components.
But, the heart of the solar panel is the solar cell. Solar cells are made from an abundant resource; silicon.
An intricate manufacturing process produces either Monocrystalline or Polycrystalline solar cells.
Monocrystalline cells are made up of solid, uniformed silicon slices, whereas polycrystalline cells are made of small silicon pieces fused together.
CHAPTER 3
Monocrystalline vs Polycrystalline
When comparing the two cell types, we’ll be looking at efficiency, price, manufacturing and application .
That’s why it’s good to learn about the different cells available .
Each has its place in the solar market, but the application will dictate which product is best for you .
Monocrystalline
The Monocrystalline panel is cut from a single crystal structure. Out of the different varieties, they are the oldest technology. The solar cells have a uniform flat colour.
Note: They are more expensive per watt but are more efficient; this means you can install fewer high-efficiency panels.
Best used:
Residential and Commercial projects
If there is limited space available
Pros
- Most efficient
- More heat resistant
- Durable
Cons
- Most expensive per watt
Polycrystalline
The polycrystalline panel is a newer technology. Due to the cells being made up of fused together pieces of silicon, they have a less uniform appearance.
They tend to be the most affordable with the lowest price per watt; although they put out a little less power, they are becoming more efficient.
Note: Their production is better for the environment as they require fewer resources to make, making them the “greener” option.
Best used:
For Grid-Tied systems
Best Solar Panel price
Looking for the “greenest” option
Pros
- Most affordable
- Long-lasting
- Require less silicon
- Durable
Cons
- Least efficient
CHAPTER 4
Solar Panel Sizing
Your personal needs will determine what size solar panel will suit you .
If you have little space for panels, you will need a higher power rating panel , like a 400W panel.
If you have a lot of space, then you can look at having more lower power rating panels .
New Technology
Solar Panel sizes are changing all the time for bigger and better panels. For instance, the panels we now sell are vastly bigger in rating than the panels we were selling between 2 and 3 years ago.
Naturally, with the betterment in solar panel technology, obsolete tech has now been abandoned. Therefore, making it near impossible to find those 180W panels you bought back in 2018.
Adding To An Old Array
You may have an existing solar array and need to add solar panels a few years down the line, how will we still be able to help you?
Voltage plays a huge roll in being able to add to your array. Absolutely any panel with more than a 5V difference will simply not work and will cause you a lot of frustration. Additionally, it is important to say that your adding larger panels to an array that contains smaller panels will see your new panels performing as well as the old panels.
However, if you have an inverter with multiple MPPTs and have an MPPT available, you can add whatever panel you’d like.
For First Time Buyers:
In conclusion, when choosing panels for a new setup, our advice would be to ensure you choose the biggest size panel that your inverter will allow. Moreover, if you want to maximise your array later, do it within 6-12 months after buying your current setup. Because, there are no guarantees that the size panel you want will be available.
Want to know how to size an array?
We have a array sizing guide that will further explain how to size an array based on your needs and your inverters parameters.
Click HereCHAPTER 5
Which Brands Are Best?
We stock brands such as:
- Jinko
- Canadian Solar
Both are great brands.
You can use any panel with any system, as long as you stick to the parameters set up by your inverter manufacturers.
With core values like ‘innovation‘ and ‘sustainable development‘, it’s no wonder Longi are leading the way in the solar industry.
They supply around a quater of the world’s monocrystalline needs on a yearly basis and are the world’s most valuable solar technology company with the highest market value.
Top features:
- High-quality, high efficiency solar panels
- Affordable Solar Panel price
- Global leaders in monocrystalline tech
- Great support
- Offer guarantees
- Long-lasting Panels
Canadian Solar boasts a reputation for being among the world’s three largest solar panel brands in terms of size.
Their employee base has grown to more than 9700 staff members, and the brand operates on no less than six continents.
Top features:
- High-quality panels
- Production lines in South Africa
- Affordable Solar Panel price
- Global leaders in Solar Energy
- Great support
- Offer guarantees
- Long-lasting Panels
Based in Shanghai, and it’s been operational since 2005. Over the years, the company has gained a strong reputation for producing some of the most high-performance cells and modules, and its international client base is growing at a rapid pace.
Top features:
- High-performance panels
- Innovative
- Affordable Panels
- Global leaders in Solar Energy
- Trusted brand
- Offer guarantees
- Long-lasting Panels
CHAPTER 6
Is Your Roof Suitable?
One of the important factors when investing in solar panels is how they will work with your roof .
This can be straight forward, or it can be a bit more complicated depending on your roof’s size, shape, angle, and stability .
In this section, you’ll learn more about roof types and if yours is solar-ready.
How Complex Is The Roof?
The shape and design of a complex roof will leave you at a slight disadvantage.
Though it is possible to install solar panels on complex roofs, it is going to cost more.
For example, take this beautiful house with a complex roof and compare it to the more standard design roof.
A solar panel installation on a roof like the complex roof will require elaborate mounting kits, which will take longer to install, costing you more for labour and materials.
Roof Direction
Roof direction is crucially important.
To have a productive array, your solar panels will need to face the sun all day.
You will need your roof to be north-facing in the Southern Hemisphere, whereas Northern Hemisphere arrays will need to be south-facing.
Because we are in the Southern Hemisphere, we’ll focus on north-facing examples.
If your roof is not north facing, you will still benefit from a solar system installation.
You will need to install two arrays, one on the west-facing side and one on the east-facing side.
In the morning, you’ll harvest solar power from the east-facing array, and in the afternoon, you’ll harvest solar energy from the west-facing array.
However, you will be better off using an inverter with a high voltage range with either 2 MPPTs or buying a combiner box to have more strings of panels.
What Material Is Your Roof Made Of?
The material and pitch of your roof will also affect the cost of the installation of Solar Panels.
In South Africa, most houses have tiled, pitched roofs. However, there are few other options, like metal or thatched roofs.
Tiled and corrugated roofs are perfect for installing solar panels, but thatched roofs not fit for solar panel installation because they are highly flamable.
We have many flat roofs here in South Africa, too, which can support solar panels. However, you will need specialist structures to install your panels on to be angled perfectly.
If you are unsure, it’s always best to have a professional solar installer, check your roof so that they can give you the best advice.
Tiled Roof
Shingle Tiles
IBR Roof
Flat Concrete Roof
Corrugated Roof
Thatch Roof
The Amount Of Shade Covering The Roof
Solar panels produce power by using the sun’s rays, so shading will not be helpful at all.
You will need to ensure that your roof has little to no shading from chimneys, trees and other buildings.
Trees can be trimmed back, and optimisers can be used to help in minor shading situations.
If there’s a way you can get around the shading problem, your solar installer will be able to help you come up with a solution.
Age And Support
It might not be easy to hear, but your roof has a time limit, and with this time limit comes a level of support it can provide to the solar array.
Once again, you want to contact an expert in this area and take an in-depth look at your roof’s condition.
There is a multitude of variables that go into installing panels.
The good news is that there’s usually a way around most common problems.
CHAPTER 7
Let’s Talk Cost:
The truth is that panel production is at an all-time high , while panel prices are at an all-time low , and according to the experts, the price drop trend won’t be slowing down anytime soon.
Solar Panel technology is advancing more and more, which means more efficient panels .
Solar Panel Pricing
You may have thoughts of waiting a little longer so that the price drops a little more and see what the latest models have to offer.
This cycle is never going to stop. Just like new cars and cellphones, solar panels will continue to evolve in affordability and design.
Solar panel prices in South Africa are determined by the brand, size, and type.
Monocrystalline panels are more expensive than polycrystalline, but they are more efficient.
Prices for monocrystalline solar panels start at around R2000.00. But, as we’ve said before, the price depends on a number of factors including size, brand and so on.
Don’t forget that you will need mountings for your solar panels which costs around R912.50.00 per panel for a pitched, tiled roof.
CHAPTER 8
How The Panel Fits In With A System
Panels cannot work independently ; they need other components to work as a complete system.
Understanding how each item works within a solar system will help you make the right choices when choosing a kit.
In this section, we’ll explain which products are a necessity and which products are optional .
Home Diagram
Along with the solar panels, you will also need or want the following:
The Inverter
The inverter plays a vital role within every solar system, converting the DC power to AC power.
Your panels produce DC power, and your batteries store DC power. You need the inverter to be able to use the generated and stored energy in your home.
Most plug-and-play inverters come with an MPPT installed inside the inverter, making installation quick and easy.
You can find out more about how inverters work and the different types available by reading our in-depth Solar Inverter Guide.
Want to learn more about inverters?
We have an inverter guide that will further explain how inverters work, the different types and application of each type.
Click HereBatteries
Batteries are an optional component. You are essentially using power on demand; this means they only use solar energy when the sun is shining.
Due to our ongoing load shedding dilemma in South Africa, most clients buy batteries for their systems.
If you spend most of your day at work and mostly use energy at night, batteries just make sense.
We have an informative guide on Solar Batteries, how they work, the different brands and how to calculate how many you need.
Want to learn more about batteries?
We have a battery guide that will further explain how batteries work, the different types and application of each type.
Click HereSolar Power Kits
Solar Power Kits have all the components you need; this is ideal for getting started quickly.
They have been designed with compatibility in mind, ensuring that you purchase complementary products so that no issues arise with your solar system.
When selecting products for our Solar Power Kits, we focus on quality and products that are in high demand.
We always have our clients in mind when we work on pricing and always try to keep our pricing fair.
If you don’t feel like mixing and matching different solar equipment, look at the Solar Power Kits section.
Some equipment and brands work better together; this is why buying a complete kit is not only optimal but cheaper.
The appeal when buying a complete kit includes:
- Convenience, in the sense that they have all the necessary components.
- You will save money; the solar panel price is lower when bought as a kit.
- Kits consist of equipment and brands that work well together.
- Learn all about Solar Power Kits in our in-depth article.
Learn more about Solar Power Kits
We have a Solar Power Kit guide that will further explain the different components of these kits and how they work.
Click HereCHAPTER 9
FAQ
Let’s go through so frequently asked questions regarding solar panels.
If you have a question that wasn’t covered in the article or FAQs, please contact us.
What size solar panel do I need?
It depends on the inverter you have and how much space you have available to install the array. It’s also worth mentioning that most inverters will need at least two solar panels so that the inverter picks up that there is an array.
How many solar panels do I need?
You would need to work out what your daily/monthly usage is. Your array size will also be determined by the maximum PV array input set by your inverter.
How to calculate solar system size?
We have developed a couple of calculators to help you determine what size system you will need.
Our Solar Calculator will help you size up a system. View it here: Online Solar System Calculator
What size solar panel do I need?
It depends on the inverter you have and how much space you have available to install the array. It’s also worth mentioning that most inverters will need at least two solar panels so that the inverter picks up that there is an array.
What size solar panel do I need?
It depends on the inverter you have and how much space you have available to install the array. It’s also worth mentioning that most inverters will need at least two solar panels so that the inverter picks up that there is an array.
I use at present 480 kilowat a month mainly at night,how many panels i need and size of back up battery and can i use at night a heater of 1,5 kilowat for 14 hours and what is total cost of the package?what happens in winter when here westcoast sometimes overcloud for 2 weeks?thankyou in advance also.
Hi,
480kw / 30 days = 16kw p/day
16kw / 5.5 peak hours =2.91kw solar array
2.91kw / 330w = 8.7 / 9 x 330w panels.
The storage would be according to what % of that energy is required to be used at night. So if 50% is night usage, then 8kw back up is required.
I am using 430kwh per month. I have gas stove usage 99% of the time, my geyser is retro fitted with the evt tubes.
I am interested in the hybrid grid tie system.
what system will be Ideal form me? At night I am mainly running fridge and freezer(24 hr run), TV and 1 or two two lights,rest of the lights go on only on demand.
kindly help.
Hi, thanks for sharing your monthly usage. The fact you have a solar geyser and you’re also on gas makes solar perfect for your situation.
A Hybrid system will be perfect for you, here’s how we work out the size:
430kwh * 30 days (1 month) / 5.5 (average sunlight hours a year) = 2.6kw
So the max output is 2.6kwh, BUT to be safe we advise taking an Inverter that can handle more, so you can go for a 3.6kw or 4kw kit (we highly recommend the Goodwe version), so any of the kits here except the 2kw option: https://solaradvice.co.za/shop/solar-power/solar-power-kit/hybrid-solar-power-kits/
Then you’ll need to consider your backup options, you can go for a 1.96kwh option and add later, or increase it to whatever you want, depending on how many hours you need in the evening.
Average is around 4 hours plus appliances like your fridge and freezer. You will also have the grid to fall back on if some evenings you exceed this.
Hope that helps, feel free to ask more questions, we love helping!
Good day! I am looking to bring my 980 units monthly down to under 600 units to stay in a certain tariff, i have 60A 3 phase supply (also solar geyser and gas hob)- and thought of getting a 3 phase 8kw pv solar inverter ( 30x 330W panels)for saving only (no battery backup. i have a few questions you might help me with, 1. what would the application to the city cost? 2. Will it be worth while spending R80 000 to do this? 3. i have a prepaid meter – would i need some smart meter or something. I really would like to Spend R900 instead of R2000 a month so i can pay back the system over 80 months (6 years) – does it seem possible? Thanks so much
Hi, we will reply back via email as soon as we can get to your request.
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