Do you know the difference between a solar panel manufacturer’s product warranty and the performance warranty? It would seem that many people are confused and I for one don’t blame them! There are many solar retail companies that advertise a 25 year warranty on their solar panels and this is wrong.

Firstly, the product warranty is the easy one to describe and the only warranty that I believe is important to consumers. This warranty is defined as the solar panel makers Limited Product Warranty.

The limited product warranty for most solar panels being sold in Australia is 10 years. In simple terms this means “A warranty with certain conditions and limitations on the parts covered, type of damage covered, and/or time period for which the agreement is good” Thus in respects to solar panels – the panels are said to be covered for 10 years from the date of installation against any manufacturing defects.  This includes the frame which provides structural rigidity to the panel, the glass which protects the top side of the panel, the EVA which is the glue that binds all the components of the panel, the cells where sunlight is converted to electricity and finally the junction box and connectors which transfers energy from one panel to the next.

Where some solar companies mislead consumers is on the limited Power Warranty or performance output warranty. This is the 25 year warranty offered by most solar manufacturers. Solar Panels will degrade over time and this warranty serves to tell the consumer what percentage rate a manufacturer’s module efficiency will drop by over time. This may be in the form of a limited power warranty which will state that after 10 years and then 25 years  – a solar panel manufacturer will guarantee that their solar panel will produce X amount of power as a percentage of peak minimum or a Linear power warranty which plots a linear curve of power loss over 25 years.

An example of a power warranty by Yingli Solar on their YGE series solar panel.  Yingli Solar states that their limited Power Warranty is 10 years at 91.2% of the minimal rated power output and 25 years at 80.7% of the minimal rated power output.

You may ask what is “minimal rated power output” and the answer is that is minimum amount of power that their panel WILL produce under peak conditions when first installed. The reason they use minimal as that relates to the actual rated efficiency of the panel which affects how many watts the solar panel will produce. Manufacturers won’t say maximum as most solar panels have a positive power tolerance and that means they could produce a little bit more than their rated output.

Now hopefully you can understand the complexities of the 25 year warranty otherwise known as the solar panel power (performance) warranty over your normal product warranty. My belief is that it is good for solar manufacturers to state that their panels are likely to last for over 25 years but it is wrong for retailers to refer to this as a selling tool and that is purely because the consumer may be mistaken for thinking that their solar panels are warranted against any defects for 25 years!

Nearly all solar panels being sold in Australia from 2012 onwards come with a 25 year performance warranty as standard as well as a 10 year product warranty. So, how does the consumer differentiate between the many solar brands as to what is genuine and what is shall we say ‘RISKY’?

The answer is simple. When you are looking to buy from a retailer make sure that they give you a warranty certificate that is underwritten against Australian consumer law.  The warranty certificate must state “Our goods come with guarantees that cannot be excluded under Australian Consumer Law”

To protect yourself, make sure that the solar panels are imported into Australia by an Australian registered company. The warranty certificate offered by the solar retailer must be supported by the 100% Australian registered company that imported the panels. The last thing that you want to be doing is dealing with a Chinese company official who ‘speaks no English’ if you have a warranty claim. You want to be speaking to the the Australian company that imported the solar panels.  Therefore – make sure that you have the contact details of the Australian office that will process any warranty claims in the event that the retailer or installer is not around to service the warranty claim. Make sure that the full Australian address and contact details are shown on the warranty certificate

I hope you liked my article. If you have any suggestions on any solar topics you would like explained or simplified please do email me: info@coffssolar.com.au

Mark McClurg – Managing Director, Coffs Solar Energy