Beginners Guide to Solar Panels

by Jan 23, 2022Solar, Solar Panels

Beginners guide to solar panels
Solar panel selection can be one of the most confusing aspects of having a solar power system installed…

There are always new technologies on the horizon and every installer or retailer will tell their prospective customers that their panels are the best. So, what really IS the best you may ask… Well there is no straight forward answer. In this article, we’ll break down a few aspects that need to be considered when choosing which panel is the best for YOUR home, budget and location:

  1. Type of Solar Panel (thin film, polycrystalline and monocrystalline)
  2. Type of Solar Panel Cell (p-type & n-type)
  3. Warranty & Local Backup Support
  4. The Physical Size, Wattage & Efficiency

Let’s start with the basics… What actually are solar panels and what do they do?

Solar panels are installed on the roof or on an engineer approved frame. Their job is to generate an electric current from the sun.

  • Solar cells are made mainly from silicon, a chemical with conductive properties. When the silicon is exposed to sunlight, it changes silicon’s electrical characteristics, which generates an electric current.
  • A cell is a small square of silicon (about 6” x 6”) with electrical contact plates on the face. Solar panels are made by laying out a grid of these cells on a protective back sheet and covering them with glass on the front. Most solar panels have 60 or 120 cells per panel. 
  • It takes multiple panels to provide enough power to a standard home or office. The total number of panels in your system is called an array. Panels wired into the same inverter are known as a string of panels. 
  • Inverters have a maximum string size, which limits the number of panels they can support. This is why inverters come in a range of different sizes (5kW, 10kW etc).
  • Note that while the majority of solar panels have an aluminium frame, there are now some frameless solar panels available. 
Parts of a solar panel. Electrical Sensations Toowoomba
Labelled solar panel. Electrical Sensations Toowoomba
Types of Solar Panels

There are 3 major types of panels and all have relevant advantages and disadvantages. There is not a great deal of difference between the size, price and performance between the poly and mono, but there is a great deal of difference between the poly and mono and the thin film panels. The choice of the type of panel will be largely dependent upon the amount of available roof space, climate and whether there are any shading issues. While the type of solar panels is important, the type of cell within the panel impacts the efficiency and performance of the panel much more.

Thin Film

Usually perform better than other panels in very hot climates such as northern Queensland. Can take up to 3 times as much roof space to achieve the same sized system using other types of panels.

polycrystalline

Usually perform marginally better than mono-crystalline in low light conditions such as where shading is an issue. Generally take up the same roof space as mono-crystalline system and much less than thin film.

Monocrystalline

Perform very similarly to and generally weigh less than polycrystalline. Monocrystalline will usually be slightly more efficient than polycrystalline. The LG NeON H & REC Twin Peak 4 that we install are monocrystalline.

Types of Solar Panel Cells

In Australia, there are two main types of solar panel cells: P-Type and N-Type. The type of cell is different and more important than the type of solar panel (above).

p-type

In p-type solar cells, its silicon wafer (the building block of a solar panel) has been doped with boron. Boron has one less electron than silicon which makes the cell positively charged. P-type panels are usually more affordable and are quite common. However, p-type cells may get boron-oxygen defects, which can degrade the cells and cause decreased efficiency in the first few years of operation.

n-type

In n-type solar cells, its silicon wafer (the building block of a solar panel) has been doped with phosphorus. Phosphorus has one more electron than silicon which makes the cell negatively charged. N-type cells are more efficient and are not affected by light-induced degradation (LID). The LG NeON range of panels that Electrical Sensations install contains n-type cells.

Warranty & Support

Solar panels have two different types of warranties: The Output Performance Warranty and the Manufacturer’s Product WarrantyThey are VERY different!

Performance Warranty

To be eligible to claim the STC ‘rebate’, all panels installed in Australia must have a minimum of 25 years, 80% performance warranty. There are a few solar panel manufacturers that now guarantee performance for 30 years. However, a higher performance warranty does not necessarily mean that they are a higher quality panel than other panels with a 25-year performance warranty.  

Product Warranty

In addition to the performance warranty, solar panels must also carry a manufacturers warranty which relates to defects of workmanship. The manufacturer’s warranty can vary from 10 through to 25 years and is considered to be a good indicator of the quality of the panels. It stands to reason that panels which carry a 25 year manufacturer’s warranty are probably going to last longer than ones that carry a 10 year warranty.

Back up support is provided by the manufacturer. Any warranty is only as good as the company that produces the panel or the company that sells the panels.

Does the solar panel manufacturer have an Australian office that you can easily contact? Like most things, having an Australian office makes things infinitely easier in terms of processing warranty claims if something was to go wrong. You also need to think about:

      • Will the installer be around to honour the warranty if something were to happen?
      • How long has the manufacturer been producing panels? What is their reputation in the solar industry?
Comparrison graph solar panel product and performance warrenties
Highest efficiency, not the biggest wattage

The higher the efficiency of the panels, the more watts of electricity the panel will produce, per square meter of panel. This means that the higher the efficiency, the less roof space required (lower footprint). If you don’t have a lot of room to work with, investing in high-efficiency panels is the way to go. 

Other important things to keep in mind:

  • Higher efficiency panels are typically more expensive.
  • Really high wattage solar panels are usually physically much larger. So, even though the panels are higher wattage, you might not be able to fit as many on your roof and you could end up with a system that’s smaller than needed.
Nigel Phillips
Nigel Phillips

Director/Technical Manager at Electrical Sensations

Nigel has decades of experience in domestic, commercial and industrial electrical work, as well as 14 years of experience in the Solar Industry. As a Clean Energy Council (CEC) accredited solar designer and installer for both grid and off-grid solar power and battery systems, Nigel has the knowledge and expertise to create solutions to suit every client. Nigel is also one of the 23 solar experts in CEC’s Installer Reference Group, which assist the CEC in improving and shaping the small-scale PV and battery industry. Troubleshooting, fault finding and thinking outside the box are some of Nigel’s most valuable strengths.

0 Comments

Submit a Comment

Your email address will not be published.