Is a 10kW solar system right for your home?
A 10kW system suits larger households with a pool, air conditioning or someone working from home, usually using 20–30 kWh a day. In Melbourne it averages about 37.4 kWh a day, so it covers most daytime use and exports the rest. Your last 12 months of bills are the best test: size for your daytime use first, because that is the power you actually use on site rather than export.
Who a 10kW system suits
- 4–5 people using 20–30 kWh a day
- Homes with daytime use: pool pump, air conditioning, home office
- Homes that may add a battery later (bigger needs: 13kW)
- Roofs with 47–56 m² of usable, mostly unshaded space
How a 10kW system works
Solar panels
22–26 panels · 47–56 m²
The panels turn sunlight into DC power. Facing north, east or west with little shade from 9am to 3pm gives the best yearly output.
Inverter
8 kW (panels up to 133% of inverter)
The inverter converts DC to the AC power your home uses and controls what goes back to the grid. It is the part most likely to need replacing in the system’s life.
Your switchboard
Solar first, grid second
Your home uses solar power first; anything left over is exported for a feed-in credit, and the grid tops you up at night or on cloudy days.
Monitoring
App or web portal
Monitoring shows production and use by the hour, so you can move dishwasher, washing and EV charging into sunny hours and spot faults early.
How much does a 10kW solar system cost in Victoria?
A 10kW system typically costs $6,500–$10,500 after the STC discount of about $2,242 that installers apply to the invoice. Roof type, storeys, switchboard complexity and the panel and inverter brands you choose decide where you land in that range. The cheaper end often means older panel technology or unknown brands; the higher end reflects premium panels and extended warranties.
10kW system prices and output by city
| City | Output a day | Output a year | STC discount | Price | Payback |
|---|
| Sydney, NSW | 38.7 kWh | 14,130 kWh | $2,622 | $6,500–$10,500 | — |
| Brisbane, QLD | 41.7 kWh | 15,210 kWh | $2,622 | $6,500–$10,500 | 3.5–6.9 yrs |
| Adelaide, SA | 41.4 kWh | 15,110 kWh | $2,622 | $6,500–$10,500 | 2.5–5.2 yrs |
| Perth, WA | 45.2 kWh | 16,490 kWh | $2,622 | $6,500–$10,500 | 2.8–5.7 yrs |
| Melbourne, VIC | 37.4 kWh | 13,660 kWh | $2,242 | $6,500–$10,500 | — |
| Parramatta, NSW | 38.1 kWh | 13,910 kWh | $2,622 | $6,500–$10,500 | 3.2–6.6 yrs |
| Penrith, NSW | 39 kWh | 14,230 kWh | $2,622 | $6,500–$10,500 | 3.2–6.5 yrs |
| Newcastle, NSW | 40.2 kWh | 14,660 kWh | $2,622 | $6,500–$10,500 | — |
Output from NREL PVWatts per city. STC discount at each city’s zone and the current certificate price. Prices are market guidance (estimates), not quotes.
10kW compared with 6.6kW and 13kW
Per watt, bigger systems usually cost less because the fixed costs of a site visit, scaffolding, approvals and the inverter are shared across more panels. The difference is small, so choose the size that matches your actual usage, not the lowest per-watt price.
| System | Typical price | Output a year | Price per kW |
|---|
| 6.6kW | $4,500–$7,000 | 9,016 kWh | $871 |
| 10kW | $6,500–$10,500 | 13,660 kWh | $850 |
| 13kW | $8,500–$13,500 | 17,758 kWh | $846 |
What changes the price of your quote?
- Roof: tile, tin or flat, pitch and storeys (and whether scaffolding is needed)
- Panel and inverter brand and warranty length
- Switchboard upgrades and meter changes
- Single- or three-phase supply and your network’s export limit
- Shading fixes such as optimisers or microinverters
Why the cheapest 10kW quote can cost more
Very low prices usually mean unknown panel brands, a basic inverter or a short workmanship warranty. A system that fails in year six costs more than one that runs for 25 years, so compare warranties and named brands, not only the invoice total. Ask for the warranty on panels, inverter and installation work in writing before you commit.
How much power does a 10kW solar system produce?
In Melbourne a 10kW system makes about 13,660 kWh a year, or 37.4 kWh a day on average. Across major cities the daily average ranges from 37.4 kWh in Melbourne to 45.2 kWh in Perth. Output varies by tilt angle, shading and how new the panels are, so use your own postcode estimate as the starting point.
How output changes through the year
Summer days produce well above the average and winter days well below it, because of shorter days and a lower sun angle. In Melbourne a summer day might reach 50+ kWh while a winter day drops to 20 kWh. Plan for winter bills to fall less than summer bills, and expect the annual saving to be uneven across months.
How much of it will you use?
Most homes use about 25–35% of their solar output as it is made and export the rest for a feed-in credit. Moving washing, dishwashing, pool pumps and EV charging into the middle of the day raises that share and the saving. A pool pump timer or smart charger pays for itself in a few years through higher self-consumption.
How much will a 10kW system save, and when does it pay back?
At Parramatta power prices a 10kW system saves about $1,590–$2,004 a year, so it pays back in roughly 3.2–6.6 years. After that, the power it makes is close to free for the rest of its 25-year panel life. Payback varies by city: Adelaide and Perth see shorter payback periods because of higher output and electricity prices.
Work out the saving for your bill
Enter your bill and usage in the calculator to see your own saving, payback and the best size for your home. The calculator uses your postcode to account for local sunlight, your network's feed-in rate and current STC values.
Open the solar size & savings calculator →
How many panels does a 10kW system need?
A 10kW system needs 22–26 panels, depending on the panel rating. Higher-wattage panels (475 W) mean fewer panels (22), whilst lower-wattage panels (390 W) need 26. Panel count matters only if your roof space is tight; if you have room, the choice between 24 or 26 panels makes little difference to the final bill.
Panels and roof space by panel size
| Panel rating | Panels needed | Area per panel | Panel area in total |
|---|
| 390 W | 26 | 1.8 m² | 47 m² |
| 420 W | 24 | 2.0 m² | 47 m² |
| 445 W | 23 | 2.1 m² | 48 m² |
| 475 W | 22 | 2.2 m² | 49 m² |
Area from a typical 21.5% efficient panel; allow extra for edge clearances and walkways.
How much roof space does a 10kW system need?
Plan for about 47 m² of panels, or 47–56 m² once you allow for edge clearances and gaps between rows. A 390 W panel uses 1.8 m² each, whilst a 475 W panel uses 2.2 m² each. Split arrays across two roof faces work well; east–west layouts make a little less in total but spread production across the day.
What size inverter suits a 10kW system?
Usually an 8 kW inverter. Rules allow panel capacity up to 133% of the inverter rating, which is why 10kW of panels is often paired with an 8 kW inverter; your network operator may also cap exports at a lower level, so confirm your local limit before design.
What’s included in a 10kW solar package?
A complete quote should list every item below by brand and model, with the warranty for each: solar panels, inverter, mounting rails, cables and switchgear, labour and site works, STC paperwork, grid connection application and a 5–10 year workmanship warranty. If the quote doesn't say what brand the inverter is or how long the panels are covered, ask for a revised version.
22–26 solar panels
Check: brand, model, 25-year performance warranty
8 kW inverter
Check: brand, 5–10-year warranty, battery-ready option
Mounting and cabling
Check: rails rated for your wind region, isolators
Monitoring
Check: app access, consumption monitoring
Installation
Check: accredited installer, workmanship warranty in years
Approvals and paperwork
Check: STC discount shown on the quote, network approval
Which brands are used in 10kW systems?
Solar Advice installs leading Australian and international brands. Each product page shows models, warranties, typical costs and which system sizes they suit. The best brand for you depends on your budget, roof space and how long you plan to stay in the house.
Solar panels
AikoCanadian SolarJinkoLONGiRECSunPower (Maxeon)Trina
Inverters
EnphaseSolarEdgeSungrowFroniusGoodWeHuawei
Batteries
BYDEnphaseSigenergySolarEdgeSungrowAlpha ESSEnphase IQ BatteryFranklinWH
10kW solar with a battery
Adding a battery stores daytime surplus for the evening. A 10kW system makes about 37.4 kWh a day on average in Melbourne, so roughly 19 kWh is spare on an average day for a battery to store (assuming 18 kWh home use). A battery lets you use more of your own solar and reduces reliance on evening grid power.
How much does a 10kW system with a battery cost?
| Battery | Battery installed | Incentives | 10kW solar + battery |
|---|
| 10 kWh | $9,000–$13,000 | − $2,520 | $12,980–$20,980 |
| 13.5 kWh | $12,150–$17,550 | − $3,402 | $15,248–$24,648 |
| 20 kWh | $18,000–$26,000 | − $4,434 | $20,066–$32,066 |
Incentives: Cheaper Home Batteries. Market guidance, not quotes; incentive amounts change on set dates.
What size battery suits a 10kW system?
Usually 13.5–20 kWh. A battery larger than your daily surplus rarely fills, so size it to your evening use and the spare solar your 10kW system makes. A 13.5 kWh battery suits homes that use 15–20 kWh at night; a 20 kWh battery suits those using 20–25 kWh at night or who want two days of backup.
Does a battery pay back?
A battery pays back more slowly than panels alone, because you are only saving the gap between the grid price and the feed-in credit. Incentives and virtual power plant payments shorten the payback in some states. Compare the total cost with batteries against the saving to work out your own payback.
Rebates and finance for a 10kW system
Several incentives apply in Victoria right now; most are taken off the installer's invoice. Small-scale Technology Certificates (STCs) give about $2,242 off a 10kW system. State rebates and finance options change quarterly, so confirm what is available when you get a quote. Your installer will apply incentives automatically.
Cheaper Home Batteries
About $252/kWh for the first 14 kWh, $151/kWh to 28 kWh and $38/kWh to 50 kWh (2026 rate)
Source: DCCEEW Cheaper Home Batteries, from 1 May 2026, checked 2026-10-16
Small-scale Technology Certificates (STCs)
Upfront discount: kW × zone multiplier × deeming years × STC price
Source: SRES: zone multiplier × 5-year deeming × $38 per STC, checked 2026-10-16
Solar Victoria hot water rebate
up to $1,400 locally made, $1,000 other
Source: Solar Victoria, from 1 July 2026, checked 2026-10-16
Solar Victoria panel rebate
up to $1,400
Source: Solar Victoria, from 1 July 2026, checked 2026-10-16
How a 10kW installation works
From first call to switch-on usually takes a few weeks, most of it approvals; the install itself is usually one day. The process starts with an assessment of your bills and roof, moves through design and quote, then formal network approval, and finishes with installation and meter changeover by your network operator.
- 01
Assessment
A look at your bills, roof and switchboard, in person or from satellite images. This step tells you how much daytime solar you can use, how many panels fit your roof and whether any electrical work is needed before panels go on.
- 02
Design & quote
A panel layout, the inverter and expected output, with an itemised written quote. The design is specific to your address and roof orientation so the output forecast is realistic for your home.
- 03
Approvals
Network connection approval and the STC paperwork, handled by the installer. The network checks that your inverter will not overload the local grid; this usually takes 1–2 weeks and is mandatory.
- 04
Installation day
Panels, inverter and monitoring fitted, usually in a single day. The installer arranges scaffolding if needed, fits the rails and panels, connects the inverter and runs the final safety checks.
- 05
Switch-on & monitoring
Meter change, switch-on and a walk-through of your monitoring app. Your network operator arranges the meter replacement; once it is in place, the installer switches the system on and you can see live output and savings in the app.
10kW solar system questions
How much does a 10kW solar system cost?
Usually $6,500–$10,500 after the STC discount. The roof, brands and switchboard work set the final price.
How many kWh does a 10kW system produce per day?
About 37.4 kWh a day on average in Melbourne (13,660 kWh a year), more in summer and less in winter.
How many panels are in a 10kW system?
22–26 panels: 22 with 475 W panels or 26 with 390 W panels.
How much roof space does a 10kW system need?
About 47 m² of panels, or 47–56 m² of roof once clearances are allowed for.
What size inverter is used with a 10kW system?
Usually 8 kW, because panels can be up to 133% of the inverter rating.
What is the payback on a 10kW system?
About 3.2–6.6 years at Parramatta power prices, saving $1,590–$2,004 a year.
What battery suits a 10kW system?
Usually a 10–13.5 kWh battery; about 19 kWh is spare on an average day.
Is 10kW enough for my home?
It suits larger households with a pool, air conditioning or someone working from home. Check your last 12 months of bills against the output above.
Can I add a battery to a 10kW system later?
Yes. Most 10kW inverters can be paired with a battery in future. Confirm battery compatibility and the inverter's AC or DC battery port when you choose the system, so you can retrofit without replacing the inverter.
Does a 10kW system work if my roof faces north-west?
Yes, but output will be lower than a true north roof. North-west faces receive afternoon sun and work well for homes that use power in the late afternoon. Output is usually 5–10% lower than the benchmark figures shown here.
What happens to a 10kW system output on cloudy days?
Cloudy days produce 10–25% of the sunny-day average, depending on cloud type and thickness. Winter days with cloud cover are the lowest-producing period. Battery or grid supply covers the shortfall.
Do I need planning approval for a 10kW rooftop system?
Rooftop systems are usually exempt from planning in Australia, but you need network connection approval and a building inspection sign-off on the roof. Check your local council's website for any local rules that may apply.
Helpful links
