11kW Solar System: Cost & Rebates in 2024

Ideal for big families and small businesses, the 11 kW solar setup is a fantastic option for those aiming to significantly alter their energy usage patterns. Moreover, an 11 kW solar setup provides adaptability to expand as your energy demands evolve. Let’s delve into the details of this system—its price, energy generation capability, potential savings, and the period required to realise a return on investment—allowing you to assess if it meets your requirements.

  • Initial investment costs about $11,500, with potential savings of up to $4,400 annually.
  • Typically, this system needs between 30-40 panels.
  • Maximise energy production through location/seasonality/sunlight & battery storage solutions.
  • Generates about 43 kWh of energy per day and 16,060 kWh per year.

How much does an 11 kW solar system cost?

An 11 kW solar system costs $11,500 on average, rebate and GST included. The minimum cost of the system is $9,500, while the maximum cost can go up to $16,500.

The system’s actual cost may vary widely depending on your location (the STC rebate you receive in your region), the quality and brand of the solar panels and inverter, and your solar provider.

The table below provides the average cost of an 11 kW solar system by location. Check it out.

STC zone City Average cost (rebate and GST included)
1Townsville, Darwin $9,800
2Alice Springs $10,550
3Perth, Canberra, Adelaide, Brisbane, Sydney $11,350
4Melbourne $12,050

Investing in good-quality solar panels ensures durability and a good ROI. There are no in-betweens in solar panels. You get what you pay for!

Government rebates and incentives for an 11 kW solar system

The Australian government offers rebates to eligible homeowners and businesses to help lower the cost of solar power systems and encourage more people to switch to solar.

The government offers these rebates through an initiative called the Small-scale Renewable Energy Scheme. Eligible homeowners and businesses can claim the Small-scale Technology Certificates that their system qualifies for and trade them with solar installers for a discount on the cost of the solar panels.

An 11 kW solar system qualifies for a rebate of approximately $4,958, which may vary depending on your STC zone, as different zones get different ratings based on the amount of sunshine each zone receives.

Rebate amount by location

Here is a table showing the rebate amount you can get for your 11 kW solar system based on your STC zone.

STC zone City STC ratingNumber of STCsRebate Amount
1Townsville, Darwin1.622142 $5,609
2Alice Springs1.536135 $5,333
3Perth, Canberra, Adelaide, Brisbane, Sydney1.382121 $4,780
4Melbourne 1.185104 $4,108

Note: The current STC price stands at $39.50

Learn more about solar STCs here.

Power output and energy generation of an 11 kW solar system

Power output and energy generation of an 11 kW solar system

How much electricity does an 11 kW solar system generate per day?

An 11 kW solar system generates about 43 kWh to 48 kWh of electricity per day, depending on your location, solar panel orientation, and roof orientation. The system will generate more power in the summer and less in the winter.

To make full use of this energy, it is recommended to operate heavy appliances like dishwashers during the daytime, when your solar panels produce more output than needed for daily usage.

If you want to benefit from extra production beyond what’s consumed right away, opting for battery storage will serve this purpose nicely while minimising dependence on grid-supplied energy and resulting in significant savings over time.

11 kW solar system output in major cities in Australia

Here is a table showing the amount of electricity an 11 kW solar system can generate in different cities in Australia.

City/StateDaily Power Production (kWh)Annual Power Production (kWh)
Brisbane, QLD46.2016,863
Sydney, NSW42.9015,659
Perth, WA48.4017,666
Melbourne, VIC39.6014,454
Adelaide, SA46.2016,863
Hobart, TAS38.5014,053
Canberra, ACT47.3017,265
Darwin, NT48.4017,666

Factors affecting energy production of an 11 kW solar system

The output of an 11 kW solar system can be affected by a variety of factors, including:

  • The amount of sunshine available
  • Shading from nearby trees and buildings
  • Solar panel tilt and angle
  • Local climate and weather conditions
  • Solar panel efficiency
  • Roof orientation and pitch
  • Inverter type and quality

How many solar panels do I need for an 11 kW solar system?

An 11 kW solar power system requires about 30 to 40 solar panels, but the exact number will depend on the wattage of the panels. For instance, you will need 30 370-watt or 40 275-watt solar panels to make up an 11 kW solar system. The number of panels required will reduce if you use higher-efficiency panels.


11,000 Watts / 275W (panel size) = 40 panels

11,000 Watts / 370W (panel size) = 30 panels

Here are common solar panel sizes that can make up an 11 kW solar system:

  • 275W x 40 (solar panels) = 11.00 kW
  • 300W x 37 (solar panels) = 11.10 kW
  • 330W x 33 (solar panels) = 10.89 kW
  • 350W x 31 (solar panels) = 10.85 kW
  • 370W x 30 (solar panels) = 11.10 kW
  • 390W x 28 (solar panels) = 10.92 kW
  • 400W x 28 (solar panels) = 11.20 kW
  • 420W x 26 (solar panels) = 10.92 kW
  • 450W x 24 (solar panels) = 10.80 kW
  • 480W x 23 (solar panels) = 11.04 kW
  • 500W x 22 (solar panels) = 11.00 kW

Whether you use fewer, higher-efficiency individual panels to produce the same amount of energy as a higher number of lower-efficiency panels, high-grade materials are key to getting optimal performance while reducing long-term maintenance costs at all times!

Roof space requirements for an 11 kW solar system

The amount of roof space you will need for your 11 kW solar system will depend on the size and number of panels. For example:

If you use the 275W solar panels measuring 1.6 m2 (1.6m x 1.0 m), you will need about 64 square metres of roof space.

1.6 x 40 275-watt panels = 64 m2 of roof space

On the other hand, if you use the 370W solar panels measuring 1.75 m2 (1.75m x 1.0m), you will need about 52.5 square metres of roof space.

1.75 x 30 370-watt panels = 56.2 m2 of roof space

By opting to use higher-efficiency 400W or 500W solar panels along with a more compact racking system setup, it’s possible to optimise available roof space while still ensuring that your 11kw Solar System is properly installed.

Assessing the savings of an 11 kW solar system

Assessing the savings of an 11 kW solar system

An 11 kW solar system in Australia is expected to generate substantial savings each year. When looking into the costs and benefits of the system, several factors need to be considered, from initial investments for purchasing and installing such systems to potential energy consumption patterns that can lead to significant financial rewards.

How much can an 11 kW solar system save me?

On average, an 11 kW solar system can save you around $800 to $1,100 each quarter and around $3,200 to $4,400 per year. However, how much you can save with your solar system depends on how much solar energy you can use at the time of generation.

Ideally, you can save between 22 and 30 cents per kWh, depending on the cost of electricity in your area. And if you send excess power to the electricity grid, you will earn around 5 to 13 cents per kWh, depending on your retailer.

Payback period and return on investment

The average payback period for an 11 kW solar system is 3 to 5 years, with a ROI between 10 and 20%. This makes it possible for people to enjoy considerable savings over their long-term investment in solar power.

Factors such as the cost of the system, electricity rates, and incentives should be considered when calculating both the payback period and return on investment to make an informed decision about this system.

Determining if an 11kW solar system is the right fit for you

11kW solar system is the right fit for you

Who are the ideal users of an 11 kW solar system?

An 11 kW solar system is ideal for a large 5-bedroom home with more than 5 people. It can be used by residential customers with high power needs or small businesses with low power needs.

If you are a residential or commercial customer using between 41 kWh and 65 kWh per day, an 11 kW solar system could be the ideal choice to help reduce your electric bill.

What can an 11 kW solar system run?

An 11 kW solar system can run a larger home with high energy needs. It is also classified as commercial and can run a small business with lower energy demands.

Here is what your 11 kW solar PV system can run:

  • Reverse-cycle air conditioner
  • A kitchen with large ovens and induction cooktops
  • Swimming pool and hot tub
  • Refrigerators, TVs, and lights
  • Washer and dryer
  • An electric vehicle
  • A workshop or a granny flat that needs additional electricity

Energy consumption analysis

To determine whether an 11 kW solar system is suitable for your needs, it’s essential to evaluate your electricity consumption habits and calculate whether you will get a good ROI from the system. You should also consider days with high or low energy demand and whether a higher need exists in the summer or winter.

By evaluating these patterns of power utilisation accurately, you can make an informed decision regarding whether getting this specific type of solar setup best suits your home or business structure.

11 kW solar system with battery price

An average Aussie home uses about 30% of the power generated by their solar power system during the day and will need about 70% of that energy at night.

With a battery storage system, you will be able to store the excess power your solar system generates to use during nights, overcast days, and even during power blackouts.

That said, a battery with a capacity of 30.8 kWh would be ideal for an 11 kW solar system.

How much will the battery cost?

Battery systems are quite expensive in Australia, costing between $800 and $2,000 per kWh. Therefore, a 30.8 kWh solar battery will cost about $24,640 at the minimum and up to $61,600 at the maximum.

11 kW solar power system plus battery cost

As mentioned earlier, an 11 kW solar system costs $11,500 on average. Installing this system with battery storage would cost $36,140 at the minimum, with a maximum cost of $73,100.

Maintenance and warranty considerations

It is essential to carry out regular maintenance on an 11 kW solar system to maintain optimal efficiency and safety. Understanding the warranty conditions should be done so that any necessary repairs or replacements are secured by the coverage and also to make sure claims will hold up if needed.

By concentrating closely on servicing and guarantee measures, you can secure long-term success with a reliable 11 kW solar energy system.

Routine maintenance tips

Routine maintenance tips

Maintaining your 11 kW solar system is paramount to ensuring it functions properly and efficiently. It’s advised that panels be serviced at least once a year for this purpose. Cleaning them regularly will also guarantee peak performance. Adhering to a regular maintenance schedule and keeping the surfaces spotless should help extend the system’s lifespan and improve its production rate.

Warranty Coverage

For an 11 kW solar system, a product warranty is usually offered for 10–25 years and a performance guarantee of 25 years. To provide peace of mind about your investment in sustainable energy solutions, the coverage includes defect protection in both materials and craftsmanship, as well as necessary replacements or repairs that come along with it.

Inverter warranties are commonly given between 3 and 10 years, though 5 is considered standard on average.

Inverter selection for an 11 kW solar energy system

The inverter for your 11 kW solar system is essential to ensure optimal performance and convert the direct current (DC) generated by the solar panels into alternating current.

It is recommended to choose an inverter that is slightly smaller or bigger than your solar system. In this case, an inverter with an AC output of 10 kW, 11 kW, or 12 kW would be ideal for your 11 kW solar system.

It is essential to regularly inspect the inverter for defects or other issues that can affect its energy production capabilities. Also, proper cleanliness around an inverter helps preserve its longevity to keep up with the increased demand produced by your solar panel setup efficiently over time.

How long can an 11 kW solar system last?

25 to 30 years, after which time their performance starts to decrease. Most manufacturers offer a standard warranty of 25 years for the expected life expectancy of solar PV panels.