5kW Solar systems: Prices, output and payback

A 5kW solar system is a popular choice for many Australian households as it can produce enough energy to offset average daily electricity use.

There are several benefits to 5kW systems:

• The number of panels needed can fit most household rooftops
• They can save you money and reduce your electricity bills
• They are typically suitable with solar batteries (depending on electricity use)
• They typically fall within network export limits

While a 5kW system is still a good option for many, their popularity has decreased in recent years. A 6.6kW solar system with a 5kW inverter is now a far more popular system for many Australian homes wanting to maximise their energy output and stay within network export limits.

For households wanting to move away from gas appliances and electrify their homes, a 5kW system is not likely big enough - particularly to charge electric cars.

5kW Solar system prices and costs

For a good quality 5kW solar system, you’re likely to pay around the $5,000 mark, but prices can go as high as $8,000 depending on the quality of the components and the complexity of the install. The cost of a 5kW system is impacted by three major price variables:

• Retail competition in your local market
• The solar rebate applicable to your geographic location
• The quality of the system you wish to install

5kW system prices in major cities:

The table below shows the average price of a 5kW system in major capital cities:

The prices above include the full cost of installation, GST and all associated components. Figures shown include the federal solar rebate.

5kW solar inverter cost

The prices shown above also include the cost of the inverter for a 5kW system. The quality of the inverter is one of the variants in prices between different systems.

Do not compare 5kW systems on price alone

We recommend that you consider the longevity of the system and not compare solar power systems on price alone. If you decide to opt for a cheaper system, proceed with caution, but importantly, do your homework on the installer company.

Lower price systems sometimes feature:

• Lower quality components
• Shorter or non-existent warranties
• Inferior installation
• Poor after sales service

Daily output of a 5kW solar system

A 5kW solar system can produce, on average, between 17 – 22 kWh of electricity per day. The average annual daily output of a 5kW solar power system varies according to sunlight conditions in your geographic location.

The table below shows the average daily output of 5kW solar systems in different locations around Australia:

Average output of 5kW systems:

Solar output for your property

The total amount of power a 5kW system can produce depends on your location, roof orientation, roof pitch and any shading issues on your rooftop. You can use our calculator for accurate measurement of the solar power output potential according to your site-specific conditions.

Output varies with the season

The output of a 5kW system varies according to the season. You should consider your power consumption during all seasons to ensure that you select the most suitable system size for your needs.

Is a 5kW solar system large enough?

Before selecting your system size, you should consider your future energy needs. If you are planning to buy an electric vehicle (EV), or switch from gas appliances to electric, a 5kW system will not be big enough to supply the electricity you need.

In all likelihood, a 10kW solar system or 13kW system is more suitable if you want to charge your EV with solar.

5kW systems: Savings and payback figures

Payback and savings figures 5kW systems vary according to location, property variables and electricity consumption. A 5kW system in Melbourne, for example, can payback within six years while in Brisbane it can be less than five years. Below is a snapshot from our calculator which shows the savings and payback results for a 5kW system in Sydney:

Savings vs payback

We recommend considering the lifetime savings of a 5kW solar system in conjunction with the payback period. The payback calculation tends to favour lower cost systems that may pay back faster, but do not necessarily generate greater savings over the long term. A better quality 5kW system will perform better and not deteriorate at the rate of a lower cost system.

5kW Solar system calculator

For a more accurate measurement of payback, savings and solar power output of a 5kW system for your rooftop, try our solar calculator. It displays results according to your electricity consumption, rooftop angle and orientation and solar radiation data for your postcode.

How many panels in a 5kW system?

A 5kW solar system can be made up of anywhere between 11 – 13 panels depending on the power output of the panels you select. If you buy better quality panels you need less of them.

Each panel has dimensions of roughly 1m x 1.7m, so the total rooftop area required to house a 5kW system is between 18.7m² to 22.1m².

If you have room for more panels, you may consider upsizing to a 6.6kW system or even an 8kW solar system, with more efficient modules.

5kW Solar system with a battery

Depending on your electricity usage habits, a 5kW solar system is typically big enough to power a solar battery.

Many households only self-consume between 30 – 40% of the solar energy that their system produces. If your 5kW system outputs 20 kWh per day (on average), and you consume 30% of solar electricity, the remaining 70% either goes towards charging a battery, or to the grid.

The table shows that for a typical household, a 5kW system can charge a solar battery anywhere between 10 kWh to 14 kWh in size.

Cost of a 5kW system with a battery

Adding a battery can increase the cost of a system substantially. The cost increase depends on the size and brand of the battery.