If you installed solar several years ago – first congratulations on being an early adopter. Since then solar has boomed across the country with there now being over 2 million households powering their homes with solar.
Early system sizes were quite small due to the higher cost of solar. However these days, people are installing larger systems, thanks to the increasing affordability of solar and in preparation for an all-electric home with battery storage.
So should you expand your system?
There are a couple of things to take into account when considering whether to expand an existing system:
Are your electricity bills still high? This might be because you are using more electricity during the day than your system produces. In this case, expanding your system can help you better meet your energy needs.
Considering adding a battery? Most households will need a system of at least 5kW to ensure that they have enough excess electricity to charge a battery.
Still receiving a premium feed in tariff? If your system is still working fine, you might consider upgrading after the premium feed in tariff scheme concludes. However, the right decision depends on what you are looking to get out from your solar power system. If you are looking to reduce your environmental impact or be less reliant on grid electricity, expanding your system still may be the best option.
Can I just add more panels to an existing system?
Standards have changed over time, meaning that an older system may have components that don’t meet current standards.
The latest standard change came in effect in October 2016, so if your system was installed prior to this and you would like to alter it, it’s likely it will need to be brought up to standard.
Depending on the changes you need to make, this can cost approximately $1000.
You may find that installers are not willing to alter another installer’s installation due to liability reasons. It could also make your existing installation warranty void – check the T&Cs of your installation warranty.
Options for adding more panels
Despite these challenges, there are a couple of options available:
Add a new solar PV system next to the original system
This new system can either use a string inverter system (one central inverter where panels are connected in series to the string inverter) or using a micro-inverter system (where smaller inverters are located under each panel). The advantage of this approach is that it doesn’t alter your original system, which means you can leave the old system running, without it being brought up to current standards. This is a good approach if your existing system is working well.
Remove your existing system and replace it with a new system
If your existing system is not working and you have limited space on your roof for another system, then another option may be to remove the existing system and replace it with a new system. When replacing it with a new system, we suggest fitting as many panels as your roof can fit. This will ensure you have enough excess electricity for a battery (which can be retrofitted to any existing solar power system).
If you go down this path, remember to dispose of the panels responsibly.