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.
Here's the breakdown:
- 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
- FAQ
Chapter 1
Fundamentals
Lets got from the top
- 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.
Photovoltaic
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.
Array
Photovoltaic Array refers to your solar panel setup.
String
A group of solar panels whose combined voltage does not exceed the maximum MPPT range.
Parallel
This way of connecting solar panels increases the amps.
MPPT
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?
Understanding the science
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.
To learn more about the inner workings of solar panels, watch this video:
If you'd like to read in-depth about solar panels, you can do so here.
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
What are the differences
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
How many panels can you fit?
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 inverter's parameters.
Click Here
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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