Solar Panels

Introduction

A solar panel converts sunlight into electricity. They come in different sizes and colours with different solar cell types from various manufacturers.

Selecting a solar panel for a residential or commercial solar system requires understanding the different characteristics of each type of panel and the application.

On this page we explain some of the options and aspects to consider when selecting a solar panel.

Sizes

Solar panels for grid-tied systems come in two main sizes, depending on the number of solar cells they are made from. 60 cell panels are about 1.6m tall and 1m wide, 72 cell panels area about 2m tall and 1m.

Larger panels are not better because they are bigger, they will generate the same energy on the same area of roof as smaller panels. i.e. the performance of 5 X 72 cells panels will be identical to 6 X 60 cell ones with the same energy and the same roof area. The choice is about which size of panel will best fit the available roof space.

Colours

The solar cells in a solar panel do not completely fill the area of the solar panel, there is a small gap around the end of each solar cell. Every solar panel has back sheet on which the solar cells are fixed and this backsheet can be white or black. A black back sheet looks better as it is closer to the colour of the cells but is slightly more expensive and will cause the solar panel to get hotter when it will be less efficient.

The frame of the solar panel can be silver or black. This does not impact on the performance of the solar panel but a black frame looks a bit nicer on the roof.

Cell Types

A solar panel is made using solar cells. Each cell is about 6 inches, 125mm, square. The cells are made using one of two different materials, monocrystalline or polycrystalline. Polycrystalline is slightly cheaper but is less efficient so a solar panel made with monocrystalline cells will generate more energy than one made using polycrystalline cells, but will be more expensive. Monocrystalline cells are also darker and so best used when you want a black back sheet for the best looking solar panels.

Manufacturers

There are 100s of solar panel manufacturers in the world all of who will claim to make top quality panels that will last for 25 years or more. They will all offer a warranty of 10 years or more but it is important to select a manufacturer who you can be confident will still be in business in 10 years to honour that warranty.

With major world brands like Canadian Solar, JA Solar and others you can be confident they will be around for the long term. Other smaller companies may not survive in the very competitive solar market. Often brand names you will see are not the actual manufacturer so it is important to find out who actually makes the panel and how secure they are as a business.

Between them the Top 7 solar panel manufacturers in the world made over 50% of the total panels made world-wide in 2017 and these form what is known as the Silicon Module Super League. It is highly recommended that you choose one of these brands to give you best the chance of long term reliability and performance.