Mar 14, 2025

Did you know that solar panels today generate nearly 3x more power than those from a decade ago?

Since 2010, solar panel technology has advanced significantly, increasing from an average size of just 165W to an impressive 440W or more today.

So if you installed solar years ago, your roof might already be full but producing way less energy than it could.

At the same time, household energy needs have skyrocketed with more people adding electric vehicles, high-energy appliances, and battery storage.

To keep up, solar system sizes in Australia have jumped from 1.97 kW in 2010 to 9.33 kW in 2023 and yours might be falling behind.

Image of solar PV system sizes in Australia from 2009 to 2023

Average solar PV system size in Australia from 2009 to 2023 (in kilowatts)| Statista Research Department, Jun 7, 2024

But the best part?

The solar upgrades are now cheaper than ever

As technology advances, the cost per additional kW has dropped, making it easier than ever to expand your system.

So, should you upgrade?

If your system isn’t meeting your needs, you’re likely losing out on energy savings every single day. Here’s how to decide what’s best for you.

Signs You Need a Solar System Upgrade

Infographics on signs that indicate the need to upgrade your solar system

Upgrading your solar system can boost efficiency, lower electricity costs, and give you more energy independence. But how do you know when it's time for an upgrade?

If any of these sound familiar, it might be time to take the next step:

1. Your Electricity Bills Are Still High

If you're experiencing rising electricity bills even with a solar system in place, it could indicate that your system isn't meeting your energy consumption needs.

The shortfall may result from increased household energy usage or decreased system performance. To upgrade a solar system, adding more panels or enhancing existing components can help bridge this gap and lower your bills.

2. Frequent Power Outages

Tired of blackouts? A solar system battery with blackout protection keeps your home powered even when the grid goes down. If power outages are a common issue, adding battery storage is a smart move.

3. Increased Energy Consumption

If you’ve recently added high-energy appliances or an electric vehicle (EV), your solar setup might be struggling to keep up.

Expanding your system with extra panels or a higher-capacity inverter ensures your home stays powered efficiently.

4. Underperforming Solar System

If your system isn’t generating the electricity it should, it might be due to aging panels, an inefficient inverter, or poor system design.

Keeping an eye on performance and upgrading when needed helps you get the most out of your solar investment.

5. Outdated or Malfunctioning Inverter

Solar inverters typically last 10–15 years. If yours is outdated, replacing it with a newer, high-efficiency inverter can maximise your solar power output.

6. Lower Feed-in Tariffs (FiTs)

With decreasing feed-in tariffs (FiTs), selling excess energy to the grid is becoming less profitable.

Many distributors are also introducing ‘Sun Tax’ which is a fee imposed on households with solar panels for exporting excess energy back to the grid during peak times. The charge aims to manage grid congestion caused by high solar energy input during midday hours.

For example, in New South Wales, Ausgrid plans to introduce a 1.2 cents per kilowatt-hour (c/kWh) export charge between 10 am and 3 pm. It starts as an opt-in scheme in July 2024 and becomes mandatory in July 2025.

The impact on a 5 kW system is expected to be modest around $6.60 per year.

Installing a solar battery allows you to store and use your energy instead of selling it at lower rates.

How to Decide if a Solar System Upgrade is Right for You?

If you're unsure about which solar system upgrade suits your needs, here’s a quick decision guide based on your energy generation and consumption:

Generation	Export (you can see in your last electricity bill)	Additional Roof Space?	Current System Size	Recommended Upgrade
As expected	<35%	Yes	Any	Add more solar panels to increase production
As expected	>60%	Yes	More than 6kW	Add a battery to store excess power for night use
Low	-	-	-	Contact your installer (may need panel, inverter, or system replacement)
As expected,	<35%	No	Less than 4kW	Replace the entire system for better efficiency

Solar panels produce electricity measured in kilowatt-hours (kWh).

The amount of electricity generated varies depending on sunlight hours, panel orientation, roof angle, and other environmental factors.

In Australia, 1 kW of solar panels typically generates between 3.5 kWh and 5 kWh per day, depending on how sunny the location is.

Some places get more sun than others, so your panels will produce more power in summer and less in winter.

Here’s a rough idea of how much electricity you can expect in different parts of the country.

Infographics showing on daily solar energy production, city -wise

If your solar system is underperforming, it could be due to ageing panels, shading issues, or an outdated inverter. Contact our team for a professional system assessment.

Government Incentives & Rebates Available in Australia

In 2025, Australian homeowners can take advantage of several government rebates and incentives to reduce the cost of upgrading their solar system.

1. Solar Panel Rebates

Small-Scale Technology Certificates (STCs) – Australia-Wide

The STC rebate is a federal incentive that helps lower the cost of installing solar panels. The number of Small-Scale Technology Certificates (STCs) you receive depends on your system size and location.

The larger the system and the sunnier the area, the more STCs you can claim. These certificates provide an upfront discount, making solar energy more affordable for homeowners across Australia.

Victoria – Solar Victoria Rebate

Victorian homeowners can get a $1,400 rebate when they install a new solar panel system.

Also, they can apply for an interest-free loan of up to $1,400, allowing them to pay for their system over time. The rebate reduces the initial cost of switching to solar which helps more households save on electricity bills.

2. Battery Rebates

New South Wales (NSW) – Battery Rebate

Homeowners in NSW can receive up to $2,400 in rebates when they install an eligible solar battery system.

The rebate makes it more affordable to store excess solar energy and use it at night or during peak times, reducing reliance on the electricity grid.

Victoria – Interest-Free Battery Loan

Victorian homeowners can apply for an interest-free loan of up to $8,800 for installing a solar battery.

It allows homeowners to store solar energy for later use, helping them save more on power bills and become more energy independent.

These incentives significantly lower the cost of solar and battery upgrades, making 2025 a great time to invest in an upgrade.

With these generous incentives, upgrading your solar system has never been more affordable.

NSW Solar Rebates and Incentives in 2025

Conclusion

If you want to upgrade a solar system in 2025 to maximise efficiency, reduce costs, and future-proof your home against rising energy prices, then adding additional panels, a new inverter, battery storage, or a complete system replacement are your go-to solutions.

At Zip Solar, we make the process simple. As an NETCC-approved solar provider, we ensure high-quality installations and tailored solutions to maximise your savings and efficiency.

FAQs

Can I upgrade my solar system?

Yes, upgrading your solar system is possible by adding panels, replacing your inverter, or installing a battery. A complete replacement is also an option if your system is outdated.
How do I upgrade my solar system?

You have to assess your energy needs and check your system’s current performance. If you need more power, consider adding panels or a battery. If your system is underperforming, consult a reputable solar installer like Zip Solar for guidance on replacements.