System sizes
5kW solar systems in Melbourne
A 5kW solar system in Melbourne makes about 7,097 kWh a year on a north-facing roof, around 19.4 kWh a day (PVGIS model), from 11 or 12 panels. Melbourne’s market average for one was $5,140 in October 2026, installed, solar only, after the STC rebate (Solar Choice Price Index; market data, not our price).
5kW of panels isn’t one of our solar packages: the entry package puts 6.6kW of panels on a 5 kW hybrid inverter with a 12.8 kWh battery. We give a fixed price for the package that suits your home after a free inspection.
Updated
What does “a 5kW solar system” mean?
Quotes use “5kW” for two different things, so read the panel kW and the inverter kW separately:
- 5 kW of panels: the panels’ combined rating, which decides how much power you make. Without a battery it needs an inverter of at least 3.75 kW.
- A 5 kW inverter: the most power the system can put out at once. Without a battery, the SAA Technical Requirements (version 1.9, February 2026) let it take up to about 6.6 kW of panels, because the inverter must be at least 75% of the panels’ rating. That is why our entry package puts 6.6kW of panels on a 5 kW hybrid inverter.
How much power does a 5kW solar system make in Melbourne?
About 7,097 kWh a year, and about 2.1 times as much on an average summer day as in winter, on a north-facing roof in Mount Waverley. Our calculators use the same figures.
| Season | Average a day | Season total |
|---|---|---|
| Summer (December to February) | About 26.1 kWh | About 2,351 kWh |
| Autumn (March to May) | About 16.8 kWh | About 1,548 kWh |
| Winter (June to August) | About 12.5 kWh | About 1,152 kWh |
| Spring (September to November) | About 22.5 kWh | About 2,046 kWh |
| Year | About 19.4 kWh | About 7,097 kWh |
A 5 kW inverter trims nothing from 5 kW of panels in PVGIS’s hourly model for Melbourne: over the 19 years it covers, the output never passed 91% of the panels’ rating in any hour. East and west roofs still work: 5 kW facing east makes about 6,151 kWh a year (13% less than north), facing west about 6,103 kWh (14% less), and split half and half about 6,127 kWh. Shade and pitch change these again.
How many solar panels in a 5kW system?
Divide 5,000 W by the panel’s rating and round up. The current ranges on our panels page are rated 435 to 475 W, so a 5kW system takes 11 or 12 panels, and rounding up puts the array a little over 5 kW.
| Panel rating | Panels | Array | Panel area |
|---|---|---|---|
| 435 to 450 W | 12 | 5.22 to 5.4 kW | About 24 to 25 m² |
| 465 to 475 W | 11 | 5.12 to 5.23 kW | About 22 to 23 m² |
Any panel of 455 W or more takes 11. Each panel is about 2.0 to 2.1 m². A roof that won’t take 12 panels facing north can split them across two faces, at the lower east or west output above.
5kW solar system price in Melbourne
A 5kW system is quoted installed, with the STC rebate taken off. Panels, inverter, mounting, installation, network approval and the rebate paperwork should all be in the price.
| System | Standard offer | Premium offer |
|---|---|---|
| 4 kW | $4,480 | $5,170 |
| 5 kW | $5,140 | $5,970 |
| 6 kW | $5,810 | $6,730 |
The STC rebate on 5kW, by install year
The rebate shrinks every 1 January until the scheme ends in 2030, so the install year changes the price.
| Installed in | Zone 4 | Zone 3 |
|---|---|---|
| 2026 | 29 STCs, up to about $1,100 | 34 STCs, up to about $1,300 |
| 2027 | 23 STCs, up to about $900 | 27 STCs, up to about $1,000 |
| 2028 | 17 STCs, up to about $600 | 20 STCs, up to about $800 |
| 2029 | 11 STCs, up to about $400 | 13 STCs, up to about $500 |
| 2030 | 5 STCs, up to about $200 | 6 STCs, up to about $200 |
Solar Victoria also offers eligible households a panel rebate of up to $1,400 through its authorised retailers, until 30 June 2027. Who qualifies.
5kW isn’t one of our packages: on single phase they go 6.6kW, 15kW and 19.8kW, and on three phase 15kW, 21kW and 28kW. We inspect your roof and switchboard and give you a fixed price, in writing, for the package that suits your home, with every federal rebate your home qualifies for already taken off.
5kW inverters: string or hybrid?
A 5 kW inverter comes in two kinds, and the choice decides how a battery joins the system:
- String inverter: runs the panels only. A battery added later needs its own inverter (AC coupling), and AusNet Services counts both inverters toward its 10 kW single phase limit.
- Hybrid inverter: runs the panels and a battery through one box, now or later. Our 6.6kW package uses a 5 kW hybrid. How hybrid inverters work
| Inverter | Type | Panels it takes |
|---|---|---|
| Sungrow SH-RS hybrid inverter | Hybrid | Up to 12 kWp (SH5.0RS) and 13 kWp (SH6.0RS); up to 200% on SH8.0RS and SH10RS |
| Fronius Primo GEN24 and Symo GEN24 hybrid inverter | Hybrid | Up to 150% (a 5 kW model takes 7.5 kWp, a 10 kW model 15 kWp) |
| Fronius Primo string inverter | String | Up to 150% (the 5.0 kW model takes 7.5 kWp) |
| Alpha ESS SMILE-G3-S5 hybrid inverter | Hybrid | Up to 10 kWp (200%) |
Since 1 October 2024, new, upgraded and replacement home solar systems in Victoria must be emergency backstop enabled: an inverter that talks to the network using the CSIP-AUS standard and an internet connection. Your quote names the exact inverter model and its maximum array size.
Export limits on a 5kW system in Victoria
AusNet Services and Jemena pre-approve up to 5 kW of export per phase, so there a 5 kW inverter can usually export all the solar your home doesn’t use. CitiPower, Powercor and United Energy plan to lower their fixed limit to 1.5 kW per phase, with flexible exports instead, and a battery keeps more of the midday solar.
5kW solar with a battery
Solar Victoria says most homes with solar panels only use around 25% of the power they generate, and homes with a battery around 50 to 60%. On 5kW the battery fills from the solar left over after daytime use, so the more you use by day, the less there is to store.
| Daily use | Suggested battery | Winter evenings covered | Refills on an average day | Federal rebate |
|---|---|---|---|---|
| 10 kWh (6 after dark) | 10 kWh | 100% | All year | 68 STCs, up to about $2,600 |
| 15 kWh (9 after dark) | 10 kWh | 73% | From September to April | 68 STCs, up to about $2,600 |
| 20 kWh (12 after dark) | 12.8 kWh | 38% | From October to March | 87 STCs, up to about $3,300 |
| 25 kWh (15 after dark) | 10 kWh | 17% | From October to March | 68 STCs, up to about $2,600 |
A 5 kWh battery, and the inverter’s battery rating
“5kW with a battery” sometimes means a 5 kWh battery: that is the smallest size the federal Cheaper Home Batteries Program covers (5 to 100 kWh of nominal capacity). On a hybrid, the battery charges and discharges no faster than the inverter’s battery rating, so both numbers matter. Your quote names the inverter model and its battery charge and discharge rating.
On price: a 10 kWh battery added to a battery-ready system averaged $7,784 nationally, after the rebate (Solar Choice Battery Price Index, August 2026; market data, not our price). It can’t be added to the solar price above; a quote prices the whole system.
What does a 5kW system save, and what’s the payback?
On our solar calculator’s example home, 20 kWh a day with 40% of it in daylight, on the Victorian Default Offer flat rate for United Energy (27.35c a kWh) and a 3c feed-in tariff, 5 kW of panels on a north roof saves about $920 a year: $800 from solar used at home and $120 from exports. At Melbourne’s market average of $5,140 (Solar Choice Price Index, October 2026; market data, not our price), that is a simple payback of about 5.5 years.
Most of the saving comes from solar you use: each kWh used saves your full rate, while each kWh exported earns only your retailer’s feed-in tariff, and Victoria has had no minimum feed-in tariff since 1 July 2025. The payback leans short, because the model counts all daylight use as covered by solar and leaves out panel ageing and price changes. Payback for other households: is solar worth it in Melbourne.
Smaller systems: 3kW and 4kW
On paper a 3kW system makes about the 4,000 kWh a year (about 11 kWh a day) the Essential Services Commission treats as typical home use for the Victorian Default Offer, though much of it is exported.
| System | Panels | Output a day | Market average |
|---|---|---|---|
| 3 kW | 7 | About 11.7 kWh | $3,980 |
| 3.5 kW | 8 or 9 | About 13.6 kWh | Not in the index |
| 4 kW | 9 or 10 | About 15.5 kWh | $4,480 |
Small systems cost more per kW: $1,327 at 3 kW against $1,028 at 5 kW, because every install has fixed costs. 3kW and 4kW aren’t among our packages either; a smaller size mostly suits a roof with little sunny space, and the free inspection shows what fits yours.
5kW or 6.6kW?
| System | Panels | Roof area | Output a year | Winter day | Solar STCs | Price |
|---|---|---|---|---|---|---|
| 5kW (Not a package) | 11–12 | 22–25 m² | About 7,097 kWh (on a 5 kW inverter) | About 12.5 kWh | 29, up to about $1,100 | $5,140 (market average) |
| 6.6kW (Our package) | 14–16 | 28–32 m² | About 9,319 kWh (on its 5 kW hybrid inverter) | About 16.5 kWh | 39, up to about $1,500 | No 6.6 kW row in the index |
A 5 kW inverter can carry 6.6 kW of panels, so our entry package gets 31% more power a year, for 0.5% lost on the brightest middays, and 10 more STCs from the same inverter. 5 kW of panels suits a roof without room for the 14 to 16 panels 6.6 kW takes, or low use that is mostly in the evening.
5kW solar: your questions
How many solar panels do you need for a 5kW system?
11 or 12 panels of 435 to 475 W, the ratings of the current ranges on our panels page: divide 5,000 W by the panel’s rating and round up. That is about 22 to 25 m² of roof. A “5kW system” can also mean a 5kW inverter with more panels, so check the panel kW on the quote. Panels for 5kW
How much does a 5kW solar system cost in Melbourne?
Melbourne’s market average for a 5 kW system was $5,140 for a standard offer and $5,970 for a premium one in October 2026, installed with GST and after the STC rebate, solar only (Solar Choice Price Index; market data, not our price). 5kW isn’t one of our packages: we give a fixed price for the package that suits your home after a free inspection. Get a fixed price
How much does a 5kW solar system with a battery cost?
The market indexes price them separately (market data, not our price): $5,140 for a 5 kW system in Melbourne (Solar Choice Price Index, October 2026, after STCs) and $7,784 for a 10 kWh battery added to a battery-ready system, nationally (Solar Choice Battery Price Index, August 2026, after the battery rebate). Adding them doesn’t give a real price: we give a fixed price for the whole system after a free inspection. 5kW solar with a battery
How much power does a 5kW solar system produce per day?
About 19.4 kWh a day over the year on a north-facing Melbourne roof (7,097 kWh a year, PVGIS model): about 26.1 kWh on an average summer day and 12.5 kWh in winter. East and west roofs make about 13 to 14% less. Output by season
What size battery suits a 5kW solar system?
It follows your evening use and the solar left over after daytime use. For a home using 20 kWh a day, 40% of it in daylight, the battery size calculator suggests a 12.8 kWh battery for 5 kW of panels, which refills from October to March. In winter a bigger battery seldom fills. Size a battery
How much does a 3kW solar system cost in Melbourne?
Market data, not our price: the Solar Choice Price Index, October 2026, put a 3kW system at $3,980 on average in Melbourne ($4,570 for premium offers), installed with GST and after the STC rebate. It makes about 11.7 kWh a day on a north-facing roof. A 5kW system averaged $5,140, about $1,160 more. Smaller systems
What a 5kW system means for a Melbourne home
On a north-facing Melbourne roof, 5 kW of panels makes about 7,097 kWh a year, about 1.8 times the 4,000 kWh the Essential Services Commission treats as a typical Victorian home’s use, but only about 12.5 kWh on a winter day against 26.1 in summer.
Two local details change the sums. Your postcode: most of Melbourne is STC zone 4, worth 29 STCs on 5 kW installed in 2026, and zone 3 postcodes, in some northern and western suburbs, get 34. Your network: AusNet Services (outer northern and eastern suburbs and eastern Victoria) and Jemena (northern and north-western suburbs) pre-approve up to 5 kW of export per phase, a 5 kW inverter’s full output, while CitiPower (city and inner suburbs), Powercor (western suburbs and western Victoria) and United Energy (southern suburbs and Mornington Peninsula) plan a 1.5 kW fixed limit with flexible exports above it. The network’s pre-approval for your address sets your limit.
Get a fixed price for the right size
Free inspection, no obligation. Every federal rebate your home qualifies for comes off before you see the price.
Talk to us about a 5kW system
Locally owned, locally installed. Call, email, or send the form and we’ll come out and inspect the property.
- Phone
- 0485 000 015
- Workshop
- 8/41 Ricketts Road,
Mount Waverley, VIC 3149