Should I Get More Solar Panels Than I Need?

By now, I’m sure you know that solar panels reduce your electricity bills but, in many cases, they might not always bring your bills down to zero. This makes you wonder:

“Should I get more solar panels than I need? Would a larger solar panel system mean lower bills?”

Consider Acquiring Additional Solar Panels
An image of a roof with solar panels that still has space left for more.

Well, it depends. There’s no universal answer to those questions. Lucky for you, though, I’m here to help guide you to an answer that you’ll be satisfied with. Here’s a list of topics that this article covers:

What exactly is an oversized solar panel system?

For the context of this guide, an oversized solar panel system simply means that you install a larger system than your immediate energy needs.

For example, let’s say your home currently only needs a 5 kWh solar panel system but you’re installing 6 kWh. That’s oversizing.

Having said that, “oversizing” can also mean installing a larger solar system than your solar inverter capacity — but that’s a topic for another discussion.

Recommended: What size inverter do you need?

Get 3 Solar Quotes From Quality Local Installers.

Going big: What are the benefits of oversizing a solar panel system?

1. It can future-proof your home

I say this for 2 reasons:

  • First is the rising cost of electricity
  • Second, is the degradation of your solar array

Sadly, the price of electricity isn’t going down anytime soon. There are even reports expecting a climb of up to 25%. Also, solar panels will naturally degrade, making them less efficient at the end of their lives versus when they were first installed.(1)

So, how does oversizing your solar panel system future-proof your home?

Well, for one, if you start with surplus energy production, degradation won’t hit you as hard. Meaning, you still won’t be reliant on the grid even as your solar panels lose some of their efficiency.

Moreover, your excess power will eventually be free (after you’ve paid off your solar panel system). And, at that point, it won’t matter how much electricity prices cost because you’ll be generating and using your own.

Recommended: How long do solar panels last?

2. You can drive your electric vehicle (EV) without worry

Enjoy Worry-Free Driving In Your Electric Vehicle (EV).
An image of a car being charged by a home with solar panels.

Speaking of the future, the world is moving towards EVs and Australia is no exception.

AU was one of the world leaders in electric vehicle adoption in 2021. And, in 2022, we broke that record and set another one. (2)

This circles us back to our topic. There’s a good chance that, in the future, you’re also going to want an electric car. Oversizing your solar panel system now helps prepare you for that time.

So, when you do get your EV, you not only enjoy free energy at home, you enjoy it on the road, too. That saves you a ton of money!

3. You can run energy-hungry appliances without fearing the electricity bill

The modern Australian home is run by smart appliances and you know what smart appliances need? You got it. Energy.

There are now more electric ovens than gas-powered ones. You will also find air conditioners and heaters that run from a phone app, electric water heaters instead of gas, and so on. All of these appliances need electricity.

Granted, modern appliances are also becoming more and more energy-efficient. Nevertheless, a larger solar panel system will give you the confidence to run all of your appliances without a second thought.

4. You can grow your family without caring for hefty power bills

Families grow. Homes expand. That’s just the way life goes for many people, and maybe it’s true for you, too.

Perhaps you have a baby on the way. Perhaps you’ve got cousins coming to stay during the summer. Maybe you and your partner are moving in together. Whatever the case may be, more people means an increase in electricity consumption.

Now, with an appropriate-sized solar system, you’re going to have to rely on the grid when more people come over. But, when you have a larger solar panel system, you don’t have to worry about all that.

5. Oversizing gets you closer to free electricity

The truth is that most homes with solar panels still pay their utility company. Granted, the power bills are going to be massively smaller but, yeah, it’s still there.

This is because solar panels don’t generate electricity at night.

However, with an oversized solar system and a battery to store all of your excess power, you’re going to enjoy free electricity even after the sun sets. Thus, reducing your reliance on the grid and the power bills that come with it.

Get 3 Solar Quotes From Quality Local Installers.

6. A larger solar panel system will come with larger rebates

Australia’s solar rebates are a godsend. First-timers installing solar panels can avail of hefty rebates, and logically, the bigger your installation, the larger your rebate.

This does have a limit of 100 kWh, though. But, really, most homes never even come close to needing that much energy so it shouldn’t be a concern.

The flip side: What are the disadvantages of oversizing?

1. Net metering is tilted towards the power companies.

Solar net metering is when you’re credited for sending your excess energy to the grid. In turn, these credits are subtracted from your power bill.

That being said, a larger solar panel system will generate more surplus energy. So, on paper, generating more power should mean lower electricity bills.

However, there’s a disparity between the cost of buying electricity and the credits you earn from your surplus solar energy. The cost is way too high compared to the credits.

For reference, the cost of buying electricity in Perth is about 39 cents per kWh. The credits? They’re valued at only 10 cents.

2. Oversizing will cost you more upfront.

Let’s not beat around the bush. Oversizing isn’t cheap.

A larger solar panel system will require at least a few more panels, and more panels cost more money. Not to mention, the installation fee is going to be larger, too.

Oh, and to fully maximize the power of a bigger solar panel system, additional investments such as solar batteries and a larger inverter become essential. This pushes up the initial cost even more.

Conclusion: Should I oversize my solar panel system?

After discussing the pros and cons, we’re back to our central question. I truly can’t decide that for you without knowing your budget, current needs, and future plans but I’m going to try anyway.

If you’re thinking long-term and the initial costs don’t scare you, oversizing might just be for you. However, if you’re looking for quick returns and immediate savings, a more conservative approach might be the better choice.

That being said, I recommend speaking with a professional to help you arrive at a more personalized conclusion.

Now, if you don’t have an installer yet, we can help. We have a network of pre-vetted solar installers that we trust with our own solar panels. Whenever you’re ready, we’ll get you 3 FREE quotes from them right away.


  1. https://www.theguardian.com/australia-news/2023/may/25/power-bills-to-rise-by-up-to-a-quarter-in-parts-of-australia-after-regulator-issues-market-default-decision
  2. https://www.mordorintelligence.com/industry-reports/australia-electric-vehicle-market