In Australia, the most important factor when choosing an installer is to ensure that they are “Clean Energy Council Accredited”. This is a qualification that they need in order for the government to pay out its rebates. And even more important than that it means that you can be confident that they have been trained in the safe installation of Solar Power Systems.
If you get 3 quotes through solarquotes.com.au you can rest assured that all the suppliers on our books use Clean Energy Council accredited installers.
So once you have a number of quotes, how do you choose which supplier should work on your home?
There are 4 main criteria you should look at which I explain below:
Obviously this is very important, but it may not be the most significant factor in your purchase. Remember, this is a system that you will depend on every day for 20-40 years, so it is critical that you have a system that has a quality and performance that you are happy with.
As is true with most things in this world: you generally get what you pay for. If you have been offered a system that seems spectacularly cheap then you may want to read this blog post which highlights some of the drawbacks common to a lot of super cheap solar deals.
If you are wondering what a reasonable, ballpark price is for a decent solar system, typical prices for different sized solar systems can be found here.
What performance warranties does the supplier provide? All PV panels degrade 0.5% to 1% per year, but your supplier should provide a written performance guarantee that guarantees the performance of your panels over at least 20 years.
Inverters should carry at least a 10 year warranty.
Workmanship should carry at least a 5 year warranty.
Check that the warranty is backed by an Australian Entity. I've seen cheapo deals where the Chinese manufacturers warranty states that the owner has to post the panels back to China at the customer's cost to get them tested!
Ask them how you will know if your system is performing properly. Some contractors may monitor your system over the internet, others may have a service scheme where they inspect your system regularly. AT the very least they should come back after you have had the system for a month or so to look over the electricity production figures and confirm you are getting the performance that they promised.
Above all, if the installer has good experience with the hardware he is installing, and has been doing it for at least 12 months, then he should be confident enough in his product and install to give you a minimum performance guarantee (i.e. minimum kWh per year produced) in writing.
A well fitted solar panel can be a beautiful thing. What kind of mounting system does your contractor use and how do they look and do they allow air to flow under the panels? There should be at least a 100mm gap between the roof and the panel.
Your solar system is in one hell of a harsh environment - the Aussie Sun - and unprotected cables will not last more than a couple of years on your roof. Don't accept an install that doesn't have all external wires in conduit if you want the system to last 20+ years. And good quality UV protected conduit at that.
Ask for some referrals and go look at previous installations. Inspect the workmanship, and overall simplicity of the installation. Do they use stainless steel nuts and bolts to prevent galvanic corrosion with any aluminium framing? If there is an aluminium frame on a tin roof, have they used an insulating separator to prevent galvanic corrosion? Have a look at the inverter installation. Are all the cables tidily attached to the wall (ideally in trunking).
(Note: Galvanic Corrosion is when dissimilar metals react to each other and corrode.)
Ask them how many installs they do in a day. More than 2 and they may be a bit rushed.
Having a good relationship with your contractor matters a lot for such an important project. A good relationship will ensure any problems are fixed up quickly and in a mutually beneficial way. Choose a contractor that you are compatible with. For example: If you like to ask loads of detailed questions, go with someone who enjoys explaining things in terms you can understand!
Here’s a list of questions you may like to ask: