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10kW Solar Systems

Power generation of a 10kW solar system in Adelaide

To give you a better understanding of the power output of a 10kW system, let’s consider the theoretical possibilities.

In peak sunlight (more on peak sunlight below), 1kW of panels with a 1kW inverter would produce 1kWh of electricity per hour. By extension, 10kW of panels with a 10kW inverter would produce 10kWh of electricity per hour.

So how much will this actually generate on an average day in Adelaide? As we know, the sun isn’t a light globe you can just switch on and off, directly above your panels whenever you need power. Instead, it moves across the sky under varying cloud and atmospheric conditions.

Peak sun hours refer to the quantity of solar energy available in an area during a typical day.

With that in mind, how do we estimate power output? Enter, ‘peak’ sun hours. Peak sun hours are not just hours of daylight, but they refer to the quantity of solar energy available in an area during a typical day. A peak sun-hour, specifically, is an hour during which the intensity of sunlight is 1,000 watts per square meter.

In Adelaide, we receive an average of 5.6 peak hours of sunlight a day, over the period of a year. Based on that figure, we could deduce that a 10kW system will generate 56kWh per day.

But, wait! There are some variances that ultimately reduce this figure. For example, panel angle, direction and degradation, as well as efficiency losses due to energy transfer and heat (yes, solar panels are less efficient in higher temperatures). On average these losses can reduce a system’s performance by around 25%. All of a sudden our 56kWh becomes 42kWh! That’s a significant difference, and worth noting in your decision to purchase a system.

Suitable For

Moderate to large electricity users, particularly for larger households and if there is someone home for most of the week, or for moderate to large users who want to sell power back to the grid and/or add batteries to offset evening usage.

Maximum Peak Sun Output

7.5kW (10kW, less 25% for efficiency losses)

Average Daily Power Generation


Real World Usage

(Simultaneous Usage During Peak Sun)

1x Small to medium Fridge (350W)
1x Small to medium sized ducted reverse cycle system at maximum power (7.1kW)


2x 55” QLED TV (200W ea)
1x Retina 5k 27-inch iMac (262W)
1x 1000W Microwave
1x Medium to Large Fridge (700W ea)
1x Average Clothes Dryer (3000W)
1x Small wall split A/C at maximum power (2kW)

10kW solar system prices

In South Australia, a decent 10kW solar system could cost anywhere from $6,900- $19,500*

The pricing variation comes down to the quality and reputability of the inverter(s), the panels, and the installation. In some cases you might also have site-specific requirements, such as splitting your panel arrays across multiple roof faces.

Looking for an indication of pricing for your situation? Start by getting an instant solar quote.

Instant Solar Pricing

Savings and payback on 10kW solar systems

The payback period for 10kW systems varies according to your electricity usage, roof orientation and pitch, shade and other property specifics. In general, however, you could expect to recover the cost of the system within a 3-8 year period, in South Australia.

The figures below are a guide, and may not reflect your actual costs.

Possible Payback Scenario

  • System Price:
  • Annual Savings:
  • Payback Period:
  • $7,500
  • ~$2,500
  • 3 Years

Should I consider a larger system?

In some cases, yes. Depending on your electricity usage, the size of your house, the number of people living there, your battery requirements and your feed-in tariff, among other things, a larger system could be viable. Simply put, if you’ve got the means and the roof space - even if you’re not using all of the power your solar generates - at least you’re selling it back to the grid at a profit.

Should I add batteries?

If you use more then 30kWh of electricity per day, and at least half this amount during daylight hours, adding a battery may be financially beneficial for you. A 10kW system will generate enough power to directly cover your daytime electricity usage, while also charge the battery for night time use.

How many panels make up a 10kW system?

A 10kW solar system is typically made up of between 25 and 35 panels (42m2 – 60m2). If you select the best and most highly efficient solar panels, you can occupy less roof space while still amounting to 10kW.

This number could change as panel technology improves over time.

If you’ve made it this far, well done!

We hope this has given you a good baseline to make your decision on solar. However, if you’re more lost than when you started, that’s ok, it’s complex stuff! We’d love to help - give us a call on (08) 8374 1491, or contact us here.

In the meantime, why not check out some other common system sizes.

3kW Systems5kW Systems6.6kW Systems

*This price accounts for the STC government rebate (accurate October 2020), which is scheduled to end in 2030. However, each year that you delay your installation, the rebate amount is reduced, and therefore the out of pocket expense on the purchase of a solar system increases.