Design your solar, your way.
Mix and match panels, inverter, battery and EV charging — watch the price update live, then request your build.
Tell us about your roof
We size your system to the space you have. Estimate your usable roof area and how it faces the sun.
This is an initial estimate, not a quote. Final pricing is confirmed after a free site assessment — roof condition, switchboard and metering can change the design.
How we estimate
- Prices include GST with the STC rebate already deducted.
- Battery prices include current state and federal rebates.
- Savings assume ≈ $231 per kW per year on a north-facing, unshaded roof, adjusted for your orientation and shading, plus ≈ $320/yr extra self-consumption with a battery.
- Actual savings depend on your tariff and usage patterns.
Estimated ranges only — your final quote is confirmed after a free site assessment.
Solar system sizes and prices compared
Every price below already includes GST and has the federal STC rebate deducted, so it’s what you actually pay. Build a custom configuration above, or start from one of these standard packages.
Home solar systems
| System | Best for | Price (incl. GST, after STC rebate) | Est. annual savings |
|---|---|---|---|
| 6.6kW | Just right for most family homes | $3,990 | $1,800 a year |
| 10kW | Medium homes & small businesses | $5,490 | $2,310 a year |
| 13kW | Larger homes & small businesses | $7,990 | $2,900 a year |
Commercial solar systems
| System | Best for | Price (incl. GST, after STC rebate) | Est. annual savings |
|---|---|---|---|
| 30kW | Low–medium commercial energy use | Enquire | $9,800 a year |
| 50kW | Standard commercial & industrial | Enquire | $16,500 a year |
| 100kW | Large commercial applications | Enquire | $33,000 a year |
Savings are estimates based on typical Australian usage and tariffs; your figure depends on how much of your generation you use on site. Model your own payback.
How to size your solar system
- 1
Check your daily usage
Find the average daily kWh on your electricity bill. Most Australian homes use 16–25 kWh a day; households with ducted air-conditioning, a pool or an EV use considerably more.
- 2
Match panels to that usage
As a rule of thumb, each kW of solar generates about 4 kWh a day across most of Australia. A 6.6kW system covers a typical family home; 10kW suits higher usage or a future battery.
- 3
Check your roof and phase
Panel count is limited by usable north, east and west roof area, and inverter choice depends on whether your home is single or three phase. We confirm both during the free design.
- 4
Decide on a battery
A battery lets you use your daytime solar after dark instead of exporting it cheaply. The federal Cheaper Home Batteries rebate discounts it per usable kWh, which shortens payback considerably.
- 5
Add EV charging if relevant
A 7kW charger fills most EVs overnight from surplus solar. Sizing solar a few kW larger up front is far cheaper than adding panels later.
Building your system: common questions
What size solar system do I need?
Divide your average daily usage in kWh by about four — each kW of solar generates roughly 4 kWh a day across most of Australia. A typical family home using 20 kWh a day is well matched by a 6.6kW system; add headroom if you have ducted air-conditioning, a pool, an EV or plan to add a battery.
Are the prices shown the final price?
Prices include GST and already have the federal STC rebate deducted, so they reflect what you pay. The only variables are non-standard installation factors like a tile-to-tin transition, a switchboard upgrade or a long cable run, which we confirm during the free site design.
Should I add a battery now or later?
Adding a battery at installation is cheaper than retrofitting, because the mounting, wiring and inspection all happen once. The federal Cheaper Home Batteries rebate discounts it per usable kWh, which shortens payback considerably compared to previous years.
Can I add more panels later?
Sometimes — it depends on spare inverter capacity and your network's export limit. It is almost always cheaper to size a few kW larger up front than to run a second installation later.
Do you install outside NSW, Victoria and the ACT?
Not currently. Kratos Energy installs across New South Wales, Victoria and the Australian Capital Territory. You're welcome to use the builder and calculators wherever you are.
Related calculators
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Tell us a little about your place and we’ll tailor the numbers. Everything in the list below is included, no exceptions.