5kW Solar System | Energy Output, Savings Profiles, & Others

Feature image for the "5kW solar system" article showing a house with rooftop solar panels in the middle of the forest.

A 5 kW solar system could generate 7,605 kW of solar energy per year, which means that this can save you about ~$2,700 per year on energy bills. Installing solar panels of this size will cost you roughly ~$5,700 and take about three years to fully pay off.

Plus, modern 5kW solar systems are so robust that they’re tagged to last for 25 years. That means you have about 22 years of free power. A big thank you to the sun, as well, by the way.

Cool stuff, huh? It absolutely is. So let’s get into everything you need to know about 5 kW solar systems. Here’s the list of topics we’re going to cover. You can also hop and skip a thing or two, but we do recommend reading from the top.

How much does a 5kW solar system cost in Australia?

The cost of solar systems in Australia is about $1,146 per kW on average. It’s different for each state, of course. It’s better to get quotes from CEC-certified installers for accuracy, but here’s a list you can refer to:

CityCost per kW ($)Total Cost for 5 kW System ($)

Always note that the 5kW solar system prices shown above aren’t fixed and final. The final cost will depend on a variety of factors. Thus, always have a conversation with your installer.

How much power does a 5kW solar system produce?

There are a lot of different answers to this one question, just because of the multitude of things that go into the math of it all. We have a separate write-up that tackles this specific topic, but in summary, the factors that affect solar production are:

  1. panel’s angle and tilt
  2. power ratings
  3. install location
  4. daily weather patterns

However, just to answer the question “How much electricity does a 5kW solar system produce per day?”, I listed the estimated daily, monthly, and yearly outputs for each Australian capital city below. Keep in mind that these numbers were computed using the PV Watts calculator under the following settings:

  • Roof pitch: 22.5%
  • Inverter efficiency: 96%
  • Quality and type of solar panels: Standard
  • Installation type: fixed, roof-mounted
CityDaily Output (kWh)Monthly Output (kWh)Annual Output (kWh)

How many panels are in a 5kW solar system?

To calculate this, you’ll need your solar panel’s power ratings. Then, divide your system size (5 kW or 5000 watts) by that rating. The answer you get is the number of panels you need.

Since the solar business is thriving, you have a lot of competing firms to choose from. Let’s say you choose to install the solar company Sunpower’s Maxeon 6, which has a rated capacity of 410 watts (W).

  • number of solar panels = system size ÷ solar panel rated capacity
    • 5000 W ÷ 410 W/panel
    • 13 solar panels

Now, let’s talk about a cheaper option. For example, say you’re installing panels with rated capacities of 250 watts only.

  • number of solar panels = 5000 W ÷ 250 W/panel
    • 20 solar panels

For further reading:

Get 3 Solar Quotes From Quality Local Installers.

How much roof space would you need for a 5kW solar system?

It depends on a few factors. We’d need the specific dimensions of your solar panels, as every brand has different specifications and dimensions. However, on average, residential solar panels are 1.7 meters tall and 1 meter wide.

Apart from that, we also need to consider the number of panels you’re going to install. We covered this in the previous section, but to summarize, the higher the wattage rating per panel, the fewer panels you’d need to install. Thus, the less roof space you’d ultimately need.

For this discussion, let’s assume you’re installing 410W panels at average dimensions. So, you’ll need 13 panels to complete a 5kW solar system. This means you need 22.1 square meters of roof space. Here’s the calculation:

  • Step 1: Calculate the area of one solar panel.
    • Area = height x width
      • 1.7m×1m
      • 1.7 m2
  • Step 2: Multiply the area of the solar panels by how many of them you need.
    • Required roof space = solar panel area x number of panels
      • 1.7 m2 x 13
      • 22.1 m2

The financial implications of a 5kW solar system

Apart from cost, which we’ve already covered, there’s still how much you get to save each month, your ROI and how soon it can reasonably be achieved, and your payback period. We have complete articles tackling those, but let’s discuss them a bit here.

How much money can you save with a 5kW solar power system?

Once again, how much money you save also depends on a few variables. Some of which are

  • location
  • initial cost/investment
  • monthly energy consumption
  • the electricity cost of your area

We also have a more in-depth dialog around this in another one of our articles. If you’re in a rush, you can find below wide estimates of the monthly and yearly savings you may get with each capital city.

CityMonthly Savings ($)Annual Savings ($)

Get 3 Solar Quotes From Quality Local Installers.

What about ROI and payback periods?

The amount you can save should have wowed you enough, but if it hasn’t, the ROI surely will. Your payback period is going to be sooner than it seems. Oh, payback period is just the length of time it takes you to fully payoff your 5kW solar power system.

Now, I’m sure you get the pattern by now, but this, again, will vary depending on other factors. These are the installation costs and savings.

Here’s an easy equation you can use:

  • ROI = (total savings ÷ total cost) x 100
  • Payback period = total cost ÷ annual savings

You can use the numbers listed above if you want an estimate, or you could check the table below.

CityROI (%)Payback Period (years)

If you do the math, that’s an ROI of over 1000%. Also, your payback period is just under three years. Do note, though, that these are mostly oversimplifications since we can’t simply calculate every possible thing that can occur during the time you’re using your solar system.

On average, your output won’t probably be consistently this high. Even in ideal to more realistic conditions, payback should be around six to ten years, roughly. However, even then, that leaves you with about twenty years of free solar energy. That’s still a huge win, and that’s why people are going solar.

Conclusion: Would your household benefit from a 5kW solar system?

The answer is a resounding, YES! This is especially true for most households, which have very basic energy needs. If you live alone or have a fairly small family, a 5kW solar system should be enough.

Unless, of course, you have an electric vehicle or five (who has that many?!), then it may be best to go straight for a bigger solar PV system (and some battery storage systems to boot). Also, look into solar feed-in tariff incentives your local government may have put in place. Trust us, it’s going to get you hyped!

If you have doubts, you can always ask, How much power does a 5kW solar system produce per day? Per month or per year? You can then cross reference that with your own consumption habits by checking your electricity bill.

Still need an assist? We got you. You can always ask a professional. In that case, we have a network of pre-vetted solar installers that can give you 3 FREE quotes right away.