5kW Solar Systems: Pricing, Output, and Returns

View of rooftop solar power panels for clean, free and renewable energy supply in Australian homes

5 kilowatt (5kW) solar systems have become one of the most popular sizes in Australia. This due to the combination of high energy yields and great value for money that they deliver. What are the price ranges, electricity yields and financial returns you can expect from a 5kW solar system? This article takes a look.

How many panels & how much roof space for a 5kW solar system?

A modern-day 5kW solar system will be comprised of between 15-20 panels. It will also require about 25-35 m2 of roof space, depending on the wattage of the panels and how they’re tilted. Solar panel sizes vary depending on brand and whether they are designed for commercial or residential use, but most commonly panels are around 1.7 metre by 1 metre on a 5kW system.

How much do 5kW Solar Systems cost?

Australia is home to some of the lowest solar system prices in the world, thanks to a broad combination of global and local factors. According to the Solar Choice Price Index, the average cost of a 5kW solar system in Australia as of July 2023 is about $1.13 per watt – or about $5,640 – after the STC rebate has been deducted and including GST.

Below, you can see the full breakdown of how that average cost varies by capital city in Australia.

5kW solar system average costs by Australian city

Adelaide, SA$4,880
Brisbane, QLD$4,710
Canberra, ACT$5,160
Darwin, NT$7,760
Hobart, TAS$5,880
Melbourne, VIC$4,970
Sydney, NSW$4,780
Perth, WA$4,360

Important Notes

  • This pricing includes the Goverment STC rebate and GST, but excludes state based rebates like Solar Victoria
  • These are average prices, difficult installs on concrete or tile roofs will be more expensive
  • The quality of solar system equipment you select will also influence the price

History of 5kW solar system prices in Australia

The graph below shows how the cost of a 5kW solar system has declined over the past decade. It’s broken down by state capital cities around the country.

Compare quotes from up to 7 installers in your area now.

How much power will a 5kW Solar System generate?

Sun and panels graphics

Depending a number of factors, the actual power output of a 5kW solar power system will vary. These factors include:

As mentioned in the first point above, different areas receive different amounts of sunlight. The amount of sunshine falling on a solar panel array has a direct impact on the system’s output. As a rough figure, a rooftop in Australia can expect to receive around an annual average of 4.5 hours of ‘peak sun’ (peak sun hours, or PSH) per day. This number may range as high as 5.8 PSH per day in places like Darwin or as low as 4.2 PSH per day in Tasmania. It is important to keep in mind that there will be more sun in the summer and less in the winter months.

Example: An optimally tilted, 85% efficient, north-facing 5kW solar system in Sydney, for example, would produce about (3.5 PSH x 5kW x 85% =) ~15kWh of power on a day in the peak of winter, whereas in the summer output from the same 5kW solar system would be around (6.2 PSH x 5kW x 85% =) ~26kWh. (Figures are only to be taken as rough estimates.)

What is the financial return on a 5kW Solar System?

Return on Investment symbol

The financial returns from a 5kW solar installation are a bit harder to work out, and mainly contingent on whether or not a solar feed-in tariff is available to the owner/operator of the system. Solar Feed-in Tariff schemes pay solar system owners a set amount for each unit of solar power that they export to the electricity grid.

There are network limits on whether you are allowed to export energy from your Solar PV system, and feed-in-tariffs available also vary greatly state to state.

Examples using Solar Choice’s solar power system ROI calculator

Using Solar Choice’s Solar PV System Return on Investment Calculator, we’ve calculated indicative payback periods, annual internal rates of return (IRR) and annual savings (in year 1) using 5kW solar systems for common usage situations in some major cities based on average system prices as of July 2023.

Payback times depend heavily on the amount of solar energy that you consume directly vs export to the grid (‘solar self-consumption ratio’), so we’ve included both ‘low’ (30%) and ‘high’ (50%) scenarios.

If you do not or cannot use much electricity during daylight hours, you’re more likely to be on the ‘low’ end of the self-consumption spectrum, while if you do use a lot of energy during the day (e.g. because you’re home or because you can run devices like dishwashers while you’re away) then you may be on the ‘high’ end.

Indicative returns for 5kW solar systems @ average prices 
LocationPriceEnergy RateFeed in TariffSelf Consumption RateAnnual SavingPayback Period
Sydney$4,75027c / kWh7c / kWh30%$1,0444.5 Years
Sydney$4,75027c / kWh7c / kWh50%$1,4593.2 Years
Brisbane$5,58026c / kWh5c / kWh30%$9885.5 Years
Brisbane$5,58026c / kWh5c / kWh50%$1,419 3.9 Years
Melbourne$5,42021c / kWh5c / kwh30%$7736.7 Years
Melbourne$5,42021c / kWh5c / kwh50%$1,104 4.8 Years
Perth$4,86031c / kWh5c / kWh30%$1,150 4.1 Years
Perth$4,86031c / kWh5c / kWh50%$1,680 2.9 Years

Key Assumptions

  • We have assumed that the household consumes an average of 25 kWh per day
  • We have used energy rates and feed in tariffs towards the sharper end of what’s available on the market using EnergyMadeEasy
  • Pricing is based on the Solar Choice Price Index from July 2023

Try plugging some figures into our solar system ROI calculator yourself.

Compare quotes from up to 7 pre-vetted installers in your area now.

Since 2008 our knowledge and sophisticated software has allowed over 160,000 Australian households and businesses to make a well-informed choice on their solar & battery installer.

Jeff Sykes


  1. Hi, I have a 3.75 kWh solar system with a 5kWh inverter I work during the day so I use all the electric at night, would it be better getting battery storage installed

  2. Hi there,

    I have a brand new 5 bedroom double storey house with perfect northern facing space for panels in western sydney. Currently, it’s my wife and I plus a 4 year old son. We have a large ducted system and all the usual mod cons of a family home. I was looking at a 5kw system. Do you think that would be sufficient? Thank you

    1. Hi Lathen,

      A 5kW solar system would probably work fine for your home – it’s currently the most popular system size in Australia and offers great value for money. You might even benefit from going a bit larger.

      If you’re after some quotes, feel free to fill out our Quote Comparison Request form – you’ll have instant access to installation prices from installers who operate in your area.

      Alternatively, feel free to give us a ring on 1300 78 72 73.

      Best of luck!

  3. just a question how much power can i put in my 5kw inverta it says 4000w per mppt the inverta has 2 the max power output i have is about 4kw with about 4.8 input in summer time living in townsville queensland any kind of information would be helpful

    1. Hi Stevan,
      Thank you for your comment. It is always best to speak with manufacturer to get technical advice on products as each brand is slightly different. You can search the brand name followed by Australian contact to get their head office details

  4. i need to know much it cost in cash if i want to install a solar system with power bank that provides 15 to 20 kva 24/7 ?


    1. Hi Hussien,

      Solar Choice provides Quote Comparisons for solar PV & battery storage systems in Australia. If you’re interested, fill out the form to the right of this page to get quotes from installers in your area.

  5. Hi, I am designing a completely off-grid system to be installed in Melbourne. I just have 6 LED touch screens, a larger LED Screen TV (x1) about 50″ and an internet modem. I have decide to buy a 5kw system, but I am not pretty sure about the cost of the storage system.

    I also have some generator bicycles but as you may know they only produce about 40watts per hour, nevertheless, the touch screens will be only On when the people start pedal (anyway, I am discarting this energy produced).

    I think the 5kw is fine, but how much can the storage cost?


  6. thinking of getting a 5KW inverter with 6.5KW worth of panels. At the moment, its only myself and my partner. As we both work during the day and our 2 months avg bill is about $150 (8 units avg in winter and 12 units in summer). trying to determine if it is worth it to get solar system? as we use electricity mostly after work during night time, will the solar system help reduce our bill to minimal amount or into credit? and am I investing for the future with this size of a system?

    1. Hi Sheldon,

      The way that most people get value out of a solar system these days is by self-consuming the energy as it is generated, so you’re correct that it may not be in your best interests to get a system (especially one as large as 5kW). There are two main rules for homes going solar in post feed-in tariff Australia – make sure your system is sized correctly, and try to shift your energy consumption to the daylight hours as much as possible. (Check out our simple solar system sizing estimator tool.) Any reputable installer will be up-front with you about this fact. You should also be aware that it is impossible to reduce your electricity bill to nothing without going completely off-grid because of the fact that there are fixed daily supply charges from all electricity retailers – these rates don’t disappear regardless of how little energy you purchase from the grid.

      You could look into getting battery storage for your home, but batteries are still a bit expensive. While a battery bank when combined with the right solar system size will save you a lot on your electricity bill, this doesn’t necessarily mean that it will pay for itself over 10 years (or whatever the warranty period is). However, with your energy bills as low as they are you’re probably in as good a position as any for batteries to work for you financially.

      Feel free to get both solar and battery quotes through our system – simply fill out your details in the Quote Comparison Request form to the right of this page.

      Best of luck!

  7. The example in bold above under heading “Typical power output 5kW solar system” has exactly the same PSH of 6.2 for both winter and summer yet it produces 15KWh in winter and 26KWh in summer. According to my calculations the PSH should be 3.5 hours for winter to give 15KWh.

    1. Hi Trevor – thanks for pointing out that typo. We’ve gone ahead and fixed it.

  8. We have 15kw installed and we are getting zero savings on our bill. Before we installed out QUARTERLY bill was around $1800 which is incredibly high so we got solar panels to reduce the bills. We are still getting the same bills. Both the Solar company and the Electric company are saying they are working and we are saving. How can we be saving if our usage is the same or less, and the bills are the same price. We are at a loss of what we can do now.

    1. Hi Cate,

      That doesn’t sound right at all – a 15kW system is substantial and should at least put a dent in your bill provided that you are ‘self-consuming’ a good portion of the solar energy produced (see: How to get the most of your solar PV system).

      Do you consume a lot of energy during the daylight hours? If you don’t (or can’t shift more of your usage to the daylight hours), then the company who sold you the system should have let you know that solar might not be the best option for you (or at least sized your system to meet only your daytime needs).

  9. Hi I have a 5kw system and new to all this it makes anywhere from 3.0 kW to 4.5 kW at this time of year is that about correct . I’m in Melbourne

    1. Hi Paul,

      First off we should clarify the terminology a bit – if your 5kW solar system is producing only 3-4.5 kilowatt-hours (kWh) per day, that’s definitely on the low side. Kilowatt-hours represent the units of energy produced over time, while a kilowatt is instantaneous system output. So for example, your system could be producing 3kW or 4.5kW at a given point in the course of the day, but it will be at its highest around midday, when you should be producing roughly 5kW summer or winter (depending on how your panels are tilted, but as long as it’s north facing the figure should be in this ballpark).

      What changes most in summer and winter is the total daily energy output of your system. On a good day in summer (e.g. December), you should get a good 20-23kWh from your system for the whole day, while in winter (e.g. July) you might get only about half that – 10-12kWh.

      I hope this helps clarify things. Again, if you’re only getting 3-4.5 kWh of energy per day right now, you might want to double check that you’re not getting shading on your roof or have some other problems (hopefully not to do with the system itself). If you’re seeing instantaneous output of 3-4.5 kW of power when you occasionally check the inverter, then the system is probably functioning without an issue.

    1. Absolutely – that was a mistake. We’ve updated it now. Thanks for pointing it out.

    1. Hi Ghagwan,

      Sorry, but our services are only available in Australia. Best of luck!

  10. I’m interested to buy a 5KW system with no installation.
    Any chance you can help?

    1. Hi Dirk,

      We only supply quotes for fully installed systems and don’t keep any products or parts ourselves. If you’re after just the components, some wholesalers sell complete kits (panels, inverter, cabling, mounting). Have a Google around to see what you can find.

      Best of luck!

  11. Hi there,
    Are you able to tell me what you think about
    BNB inverter
    C-sun panels
    Phono solar panels are any good.
    I live in Sunshine coast and just wanted to know how effective these are, or can you recommend another brand.


    1. Hi Nel,

      We haven’t come across BNB inverters much, but CSun and Phono solar panels are fairly well-known and commonly used here in Australia. Happy to assist you further if you want to give us a call (1300 78 72 73) or you can get an instant set of quotes from installers in our network by filling out the Solar Quote Comparison Request form to the right of this page.

  12. Could you please tell me what the Government Rebate is for 5kW (20 panels) in the Southwest of Western Australia. Postcode is 6258 (Zone 4) I believe.

    1. Hi Linda,

      Thanks for the comment. According to the Clean Energy Regulator’s STC calculator, a 5kW system in postcode 6258 would create 88 certificates. The price of certificates fluctuates – at the time of writing, Green-Bank Environmental puts them at $38 each, which would put your total discount at about $3,344. Keep in mind that it may be slightly more or slightly less, however, depending on the going rate. You’ll want to check that what you’re being offered is in this ballpark.

      Best of luck with your system.

  13. Hi ! My solar system is 5kw and the other day we took a reading of 47kw on the inverter! Interesting today was 36 digrees and overcast and only scored 21 kW ??? I’m confused as the other day was only 30 degrees and doubled today’s reading

    1. Hi Stephen,

      I’m not sure I completely follow what you’re saying – or if I do, the numbers are definitely out of whack. You’re saying that your inverter showed an instantaneous output of 47kW? That sounds impossible unless your inverter is broken. Do you perhaps mean 47W (watts?), which would be a very very low amount?

      But after thinking about it, I’m gathering that you mean 4.7kW, which would be a pretty good number – this is what I think you mean. 2.1kW on the overcast day might make sense as well – it wouldn’t be surprising if the cloud cover had reduced your system’s output by about half.

      Hope this helps!

      1. OK! Soz mate! It displayed on the inverter 21 kWh today??? 35 digrees here! Is that any good!

        1. Hi Steve,

          Yep – if your 5kW system produced about 21kWh over the course of the day, that’s on slightly on the low side but still in the ball park for most of Australia (Sydney, Brisbane, Adelaide, Perth, Melbourne). If you’re in Darwin or far north Queensland, it could be better. If you’re in Hobart, it’s pretty good.

          But assuming you’re in Sydney, the heat could be the reason that your production is slightly on the low side – solar panels do better in cooler weather, and become less efficient as the temperature rises. So in short, it sounds like things are probably fine with your system. Just in case, however, we’d recommend getting a second opinion – maybe you could ask the company that installed your panels in the first place?

  14. Hi, I want to know the total output of the system. My System parameters are following
    1. 5KW Solar System
    2. Total Peak Sunny Hours = 8 Hour (9am-5pm)
    3. CUF = 19%

    What will be the total output in a day and for an hour???

    1. Hi Ramesh,

      Normally we would ask for your location, but instead you’ve provided us with the number of peak sun hours available in your area. The CUF isn’t really relevant to the calculations because this is already indirectly incorporated in the number of peak sun hours.

      In that case, the calculations are relatively easy: 5kWp x 8PSH = 40kWh per day – as long as your system is north facing (or south facing if you’re in the northern hemisphere). It’s best to assume only 80% efficiency just to be conservative: 40kWh x 80% = 32kWh.

      Hope this helps. Please keep in mind that these are back-of-envelope calculations only and should not replace the advice of an accredited installer who knows about all of your individual circumstances.

  15. We live at Robina on the Gold Coast and have just received our first full power bill after having 5Kw solar system installed with a 6 cent feed in tarriff. Our previous bill (which had the solar included for only 30 days) showed a significant reduction of 30 percent to our overall bill and a feed in credit of $36. So we were anticipating a significant reduction in our first full summer quarter but were extremely disappointed. Our bill says our average daily use is 4 Kwh MORE and average cost per day is exactly the same as the previous year! We are producing the maximum power allowable and our power usage has increased by 10 percent. How can that be?

    1. Hi Julie,

      Sorry to hear you’re having problems. Are you sure that there isn’t currently an issue with the system? It sounds highly unlikely that you would have excellent performance one quarter followed by no benefit the next. Either you’re using a lot more electricity this month (so much more that the solar isn’t making a difference) or there’s a problem with your system.

      Please also note that you should endeavour to use as much electricity during the day as possible to maximize the amount of money your solar panels can save you. You can read more about this here.

  16. Hi, I have a 5kw system. I live in a Rockhampton, Qld.(it’s hot!) My panels produce on average 15-16kwh /day. My sister, who lives across the road from me and has the exact same system install produces 41kwh/day. I’m not sure why? Can you offer any suggestions.
    Thanks in advance.

    1. Hi Kellie,

      Those figures don’t sound right at all–is 41kWh/day from your sister’s system a summer figure? I assume they’re both 5kW systems.

      Are there any trees or other objects that could be casting shadows across your panels during the day?

      More questions: Have you contacted your installer? Do you have a monitoring system set up? Depending on the answers to these questions, you can begin to get to the bottom of this situation.

      Best of luck!

      1. Thanks for your reply. Yes, the 41kwh is a summer figure (both figures gathered on the same day, both exactly the same 5kw system, no trees or shade covering either system). My sister is about $1000 in credit with Ergon Energy, whilst we’re lucky to get $350 off our $850 bill) no monitoring system set up. I think I will contact the installer to come out and check everything.

        1. Hi Kellie,

          Yes–that’s probably the best move. By the sound of it, something might be wrong with one of your strings of panels. It could even be that you have just one defective panel knocking out the rest in that string, but you’re best to speak to an expert about how to remedy that.

          Best of luck!

  17. I am interested in the 5KW or 10KW, is it enough for the family of 4 people and what about supply and installation cost?

    1. Hi Nam,

      Whether a 5kW or 10kW system is sufficient for such a household would depend on your daytime electricity usage. In today’s Australian solar scene, with feed-in tariffs at low rates, it’s critical that a solar home or business consume as much of its power during the daytime as possible–so an oversized system would be counterproductive.

      Any of the installers in our network (or our own staff) can help you out with determining a system size. Request a Solar Quote Comparison go start up a dialogue with us.

    1. Hi Pino,

      You can get a free, instant comparison of about 7 solar PV system installation price quotes for your area of Victoria by filling out the form to the right of this page and then checking your email inbox. We hope to hear from you soon.

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