Can I just add more solar panels to my roof to upgrade my existing solar system?

Do you have a solar panel system that's too small for your home?

Either it's not providing enough power for your home, or you want to be able to sell more energy to the grid and increase the benefit.

Can you add more solar panels to the roof to upgrade the existing system?

The answer is a little complex, and you should consult with a professional before making any decisions. But here are the basics that you should be aware of first.

Will the new panels be eligible for the STC rebate?

Yes, the new panels will be eligible for the STC rebate if certain conditions are met.

Currently the average size of a solar panel is 330+ watts. At today's current rates a 330W panel receives a rebate of approximately $175 per panel! This is definitely nothing to sneeze at, so it is important for the new panels to comply with the conditions required to be eligible for the STC rebate.

Furthermore it may also not be legal to add panels to the existing system if these conditions are not met as some relate to new Australian Standards that have been introduced. These conditions will be touched on in the following content.

You May Need to Get Another Inverter

Inverters are able to have arrays oversized to approximately 133% of their original rating for the new panels to qualify for the STC rebate. If your inverter can't support the new panels, you're going to need to replace it with a larger capacity inverter which can be an expensive exercise.

The solar industry is also a very new and progressive industry and Australian Standards have changed and been updated many times in recent years as a result. One particular change in 2016 was a change to an Australian Standard requiring inverters to have special grid settings inbuilt as standard, settings that inverters from the years prior do not have nor are capable of having . To qualify for the STC rebate for new installed solar panels the inverter they are being connected to needs to be listed on the current Clean Energy Council list of compliant inverters and more often than not an inverter model installed before 2016 will not be on this list and therefore the panels cannot legally be added to the inverter nor will they be eligible for the STC rebate.

But that doesn't mean that you can't change your installation, it just means that you're going to need to find another way. The better thing to do could be to install another inverter and a completely separate system and avoid having to alter the existing system completely.

Did You Buy Your System from 2007 through 2012?

If you purchased your system during this period, it's likely that you've been told you can add panels to your existing system. But that was something that people were told regarding the technology of the time. Instead of a complete installation, people were told that they could expand their existing infrastructure, and immediately start gathering solar energy.

It's technically possible, but actually unlikely. Though it was true at the time, solar panel technology has improved since then. The solar panels that are available today aren't generally going to be able to be integrated with older systems easily, if at all, plus as mentioned above the inverter may no longer be compliant.

So even though theoretically you can expand your installation this way, on a practical level it may not be possible.

You can create an entirely new system and then augment your older system, and that will work. But it isn't going to be a single system, it's going to be two systems creating the same pool of energy. That's still useful and usable, it's just something that you're going to need to consider, in terms of the installation cost.

Australian Standards for Solar Panel Installations Have Changed

Consider the fact that Australian standards for solar panel installations have changed over time. Though you may be able to add more solar panels to your installation, the new panels may make it so that your installation isn't up to code. Your entire installation would need to be updated and brought up to current standards which in most cases is cost prohibitive and it is more cost effective to just replace the entire system.

In general, these issues are "grandfathered in" for people who already have installations. If your current installation doesn't meet code, it's not going to be an issue until you try to modify it. But once you modify it, you are going to need to concern yourself with the new codes. Your solar panel company can help you explore the changes that you might need to make to your existing installation.

Malfunctioning Systems Can Be Changed Out

What if your current system has stopped working?

If your system has stopped working, you can repair the faulty component or exchange it for a like-for-like product. Only when a system is being expanded does all the extra red tape listed above become an issue. Therefore if your inverter or panels need to be replaced and the existing product is no longer available, they can simply be exchanged with new ones of equal size/capacity. However trying to find a compatible panel today for a 5 year+ system will be quite a challenge.

Solar panel technology has advanced leaps and bounds in the last 10 years and a 5kW system today can outperform a brand new 5kW solar system of yesteryear considerably. As the new panels or a new system are all eligible for the STC rebate it could very well be that at this moment in time while the STC rebate is still rather generous the best option is to just pull out the small old, malfunctioning system and replace it with a new brand new larger system.

Network Operators are Reducing what we can Export to the Grid

In South Australia we could export up to 10kW per phase (30kW total) up until May 2019 when it was reduced to 5kW per phase (15kW total).

In general the majority of domestic properties have single phase supplies so most houses are limited to a 5kW export limit.

However there is talk that this may be reduced down to 3kW or less in the near future, so if you are considering upgrading the size of your system it is something that needs to be decided on sooner rather than later!

If you're looking to add more solar panels, we can help. Contact us toda to find out more about how to improve your energy output.