Skip to main content

Questions you should ask before installing solar

Solar power has many benefits. From making your energy consumption more sustainable to significantly reducing your electricity bills. So where do you start?

To help make your journey towards solar a little smoother, here are some useful questions to ask when getting a solar system.

Is my roof suitable for solar panels?

The first thing you need to consider is your roof. How old is it? Does it need any repairs? Whether it’s due for a touch-up or a full overhaul, get it sorted before installing your panels. Making sure you get this done will keep everyone safe and save you money in the long run, as the weight of a solar system could further damage your roof – and your shiny new panels.

What size system do I need?

Generally, a single 1kW solar panel can generate 4kWh of electricity a day. This means a 4kW system will typically create about 16kWh of electricity on a sunny day, with optimal panel orientation.  On average, Australian households use about 15-20kWh of electricity a day, so this system would be expected to cater to most of their energy needs.

Of course, every household is different, so the size of your system may need to be larger or smaller than this depending on a few factors. To get an idea of this, consider how many people live in your home, your most recent energy charges and when you use the most power.

Check your meter before and after work one day, then again the next morning to see your energy usage. Or if you’re an AGL customer, check out your usage on the AGL app.

How much north or north-west facing space your roof has, also influences how many solar panels you should install. Suppliers will be able to check this for you if you can’t.

When you start planning your solar system with your provider, they can give you a general outline of what size system you will need, how many panels it will require, and what your output will look like based on the factors above.

Can I start with a few panels and upgrade in the future?

Most of the time yes, you can add panels if your home’s energy requirements change and you need an extra boost. But this requires some future planning with a system design that's flexible to upgrades.

If you would want to add upgrades like extra panels in the future, we recommend asking your supplier if they can cater to this, so they can help you plan ahead.

Solar batteries are also a great upgrade to consider, as they can help maximise the power your solar panels produce by storing unused energy for later use. If installed later, they require a compatible inverter and a bit of rewiring. So if your budget allows for it, we suggest getting everything you need upfront so that you can get the best bang for your buck.

How long do solar panels last?

If installed properly and looked after, your solar panels can provide clean energy for over 25 years – and many providers back their products with performance guarantees and extensive warranties.

To keep your panels in ship shape, it’s important to ensure they are clean and debris-free. Monitor their performance and your energy bills so you can jump on any issues early. If you need any professional maintenance or cleaning, ask your solar provider if they can help directly, or refer you to a qualified service provider.

How long will my solar system take to pay for itself?

This is difficult to predict because everyone’s usage and requirements are different. But your supplier should be able to calculate an estimate based on the kilowatts of power your system will produce, how much solar-generated energy you’ll be using instead of exporting back to the grid and your potential feed-in tariff.

A feed-in tariff is what an energy retailer pays you for each kilowatt-hour of unused solar energy your system exports back into the grid.  We've estimated a payback period for three different solar systems to help you make an informed decision.

Jump on government solar rebates

The Federal Government is helping Australians switch to solar energy through nationwide rebates.

Check out the current rebates available in your state.

Access better battery finance

If you plan on adding a solar battery to your solar system, our solar battery bundles and an interest-free finance offer in partnership with Plenti can help with the upfront costs. And when you sign up for our Virtual Power Plant, you get up to $1500 off the upfront cost of your battery.


What is the feed-in tariff in my state?

The feed-in tariff (FIT) is an amount your energy retailer pays you for each kilowatt-hour of unused electricity you export back to the grid. The amount varies from state to state and by energy retailer.

If you're already a customer of ours, or looking to switch over, you can get an estimate of what your energy bill would look like annually with feed-in tariffs.

Where should I position my panels?

Your solar provider has the tools to help you plan your system set-up, so it's unique to your home and energy needs.

To help with this, they may visit your home, or use online mapping tools to advise you on the best position for your panels. Panels can be split across different areas of the roof to avoid shade and maximise energy production. And tilt frames can be installed to position panels to capture maximum sunlight.

What about warranties?

Solar power is now more accessible than ever. However, asking about warranties is still important so you have peace of mind. There are usually four kinds of warranties for your system.

Panel Performance: Most manufacturers will give their panels a 25-year performance warranty. It covers you in case panels degrade faster than they should over their lifetime.

Panel Product Warranty: This covers you for any faulty modules that may affect panel performance. The length of this depends on the provider and is usually between 10-15 years. High-quality solar panels boast an even longer warranty of up to 25 years.

Inverter Warranty: Your inverter is vital to your system, so it’s covered under a separate warranty. This is usually 5 years, but it can be longer.

Installation Warranty: Solar installers accredited by the Clean Energy Council (CEC) must provide a 5 year workmanship warranty. We recommend using a CEC accredited installer so you can have the assurance of this warranty and know your system was installed to align with industry best practice standards.

How solar energy can power your home

As Australia’s leading energy retailer and generator, we’re moving faster towards a cleaner energy future. Rooftop solar is an important part of this change, and you can play your part in the transition.

Related articles