KEY POINTS
- Solar panels come in a range of sizes, but are often divided into ‘residential’ and ‘commercial’ categories based on their dimensions.
- The right size panel for you will depend on a range of factors like your roof space and your energy saving goals.
- Solar panel wattage ranges from 350W to 500W depending on the type and size of the panel.
If you’re in the research phase of your solar journey and aren’t too sure on the best solar panel size for your solar system, then you’re in the right spot. In this Canstar Blue guide, you’ll find information on solar panel sizes, output efficiency, how many panels you’ll likely need, and much more to help you find the best solar system for you.
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Average solar panel size in Australia
Before we start, it’s important to note that the ‘size of a solar panel’ can refer to either the energy it generates or its physical size. The power a solar panel generates is measured in watts (W), with one kilowatt (kW) of panels producing roughly four kilowatt hours (kWh) of usable electricity per day. The average solar panel in Australia is somewhere between 350 – 500W.
When it comes to the physical size of your panels, you can expect a standard panel to be around 170cm by 100cm, but this will vary between brands and residential and commercial panels. Typically, a larger panel will generate more power due to housing more solar cells, however there are many factors that affect the size and output.
When you’re building a solar system, you can choose between a few large panels, or many smaller panels. A Canstar Blue survey of Aussie solar customers found that the average solar system size in Australia is 6kW, which adds up to around 18 panels generating 370W or 13 panels generating 500W.
Average size of residential solar panels
A standard residential solar panel typically measures 170cm by 100cm (1.7m²) and contains 60 solar cells. This means that a 5kW solar system made of 370W panels will require at least 25m² of roof space. Depending on the space available, it might make sense to purchase panels with a high output to save space.
Average size of commercial solar panels
Despite the name, commercial solar panels can also be installed on residential properties, although they’re designed for commercial use. These panels usually come with 72 solar cells and measure around 2.3m². While they’ll likely cost more, one benefit of a larger panel size is that they’ll typically have a higher output per m² due to less space being taken up by the panel casing.
How many solar panels do I need?
Here are four key factors to consider when determining how many solar panels your home will need:
- Household energy usage: Take note of the average daily usage in kWh on your energy bills over time. You can then compare this to the total output of the solar system you’re considering.
- Hours of daylight/sunshine: Solar panels work by being exposed to direct sunlight, meaning the amount of daylight in your location will be a significant factor. You’ll also want to consider seasonality, shade and your geography, as these will all affect the amount of sunlight you get.
- Roof space and suitability: To choose the right amount of panels, you’ll also need to consider your roof space and positioning. Obviously, the size of your roof will affect the amount of panels that will fit, but the positioning can also play a big role. For example, North-facing solar panels are regarded as the best for energy output in Australia.
- Personal energy goals: This is where future-proofing can come in handy. Are you looking to just use solar energy to cover your power usage during the day? Or, do you want to add a solar battery to your panels down the track to store leftover energy for use at night?
How many solar panels needed per system size?
Here are the number of solar panels you’ll need if each panel’s capacity is 370W. Keep in mind one kilowatt (kW) equates to 1,000 Watts (W). This is a general guide only.
| Solar System Size | Approximate number of panels |
|---|---|
| 2kW | 6 |
| 4kW | 12 |
| 5kW | 14 |
| 6.6kW | 18 |
| 8kW | 22 |
| 10kW | 28 |
How much solar power do I need?
The right amount of solar power for you will depend on your personal goals and energy needs. Do you want to reduce your energy costs, or are you looking to completely offset your power bills through solar? Once you’ve identified your energy-saving goals, it’s time to look at some recent electricity bills and note down how much power your home consumes on average per day.
While going bigger with solar may benefit larger households that use a lot of energy during the day, it’s always best to talk to a licensed installer before jumping straight in.
Check out our state guides to solar installers below:
Compare Solar Energy Plans
Solar-specific electricity plans are offered specifically to solar customers, and usually feature a higher feed-in tariff than standard power plans. Be sure to check all rates, fees and charges before signing up.
Here are some of the cheapest solar-specific deals from the retailers on our database. These costs are based on the Ausgrid network in Sydney but prices will vary depending on your circumstances. We show one product per retailer, listed in order of lowest price first. Annual price estimates assume general energy usage of 3900kWh/year for a residential customer on a single rate tariff. Price estimates exclude solar feed-in tariff credits. These are products from referral partners†. Our database may not cover all deals in your area, and please check retailer websites for up to date information.
Here are some of the cheapest solar-specific deals from the retailers on our database. These costs are based on the Citipower network in Melbourne but prices will vary depending on your circumstances. We show one product per retailer, listed in order of lowest price first. Annual price estimates assume general energy usage of 4000kWh/year for a residential customer on a single rate tariff. Price estimates exclude solar feed-in tariff credits. These are products from referral partners†. Our database may not cover all deals in your area, and please check retailer websites for up to date information.
Here are some of the cheapest solar-specific deals from the retailers on our database. These costs are based on the Energex network in Brisbane but prices will vary depending on your circumstances. We show one product per retailer, listed in order of lowest price first. Annual price estimates assume general energy usage of 4600kWh/year for a residential customer on a single rate tariff. Price estimates exclude solar feed-in tariff credits. These are products from referral partners†. Our database may not cover all deals in your area, and please check retailer websites for up to date information.
Here are some of the cheapest solar-specific deals from the retailers on our database. These costs are based on SA Power network in Adelaide but prices will vary depending on your circumstances. We show one product per retailer, listed in order of lowest price first. Annual price estimates assume general energy usage of 4000kWh/year for a residential customer on a single rate tariff. Price estimates exclude solar feed-in tariff credits. These are products from referral partners†. Our database may not cover all deals in your area, and please check retailer websites for up to date information.
What is the best solar panel size?
The best solar panel size is one that fits on your roof, suits your budget and meets your energy needs. As the price of solar continues to fall, it may be worth looking into a bigger PV system with higher panel efficiency. Ultimately, the best size panels for your property will depend on what’s most important to you; a cheaper brand with lower upfront installation costs or investing in panels with greater output capacity?
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How much do solar panels weigh?
In Australia, the average solar panel weighs between 18 and 22 kilograms. This will of course depend on the brand and type of panel. You can usually find the dimensions of a solar panel on the brand or manufacturer’s website, or by speaking to your preferred solar installer.
Compare Solar Energy Providers
Image credits: Joseph Sohm/Shutterstock.com
Original author: Jared Mullane
FAQs about Solar Panel Size
Most roofs in Australia can support a residential solar system, particularly on newly built properties. Any roof in good condition should be able to withstand the weight of solar panels, but if in doubt, it’s best to get an installer to assess your roof to see if it’s in need of any repairs.
While the quality and energy output of your panels are the real difference maker, there are still a few things to consider about the size of your panels. Here are some common pros and cons of larger solar panels:
Pros
- Less framing means more energy per m²
- Requires fewer inverter connections
- Potentially quicker installation
Cons
- Limits solar system design
- Heavier panels may lead to higher installation costs
- Faults can lead to higher repair or replacement costs
A bigger solar system doesn’t automatically translate to lower energy costs, but it may help future-proof your household’s consumption needs. For example, if you decide to install a solar storage system or purchase an electric vehicle and your usage habits change over time, then going big could be an ideal option.
That being said, if you don’t use a lot of electricity and don’t expect to in the future, spending more on a bigger solar system may not provide the best value long term. This is because you’ll still be paying a fixed daily fee for being connected to the grid, and you’ll still be paying for energy at night or when weather is poor and there’s a reduction in solar power output.
That’s why it’s always best to talk to a licensed installer to discuss your circumstances. Most solar installers provide free quotes so there’s no harm in picking up the phone or shooting off an enquiry.
While you might pay more for a larger solar panel, you’ll typically want to consider the price you pay per watt, not for each individual panel. When you’re installing a solar system, a lot more goes into the cost than the panels themselves, and you may find that a larger system costs less per watt.
Finding the best solar panel will depend on a range of factors, including your budget, what size system or output efficiency your home needs, and the products on offer from installers near you. That being said, there are a number of premium solar panel brands that are highly regarded within the industry, some of which include:
- Canadian Solar
- Hyundai
- LG
- JA Solar
- Jinko Solar
- Panasonic
- Q-Cells
- REC
- SunPower
- Tindo Solar
Keep in mind the ‘best’ panel for one household may not be the best for another, particularly in terms of overall value. Most solar installers will give you a range of PV panel options to choose from.
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