SolarScorecard
SA · STC zone 3 · prices updated October 2026

8kW Solar System Adelaide 2026: $5,380–$7,810 installed

18 panels, about 36m² of roof, 11,388 kWh a year. After the $2,203 federal STC discount a 8kW system in Adelaide costs $5,380–$7,810 installed and pays back in 2.6–3.6 yrs. Prices refreshed monthly — last October 2026.

Updated 19 October 2026 · Prices updated October 2026

5kW6.6kW10kW+

At a glance · October 2026

$5,380–$7,8108kW installed
$2,203STC discount
18 × 440WPanels
11,388 kWhYearly output
2.6–3.6 yrsPayback

What a 8kW solar system costs in Adelaide (October 2026)

Installed and GST inclusive with Tier 1 panels and a quality string inverter, a 8kW system in Adelaide is $5,380–$7,810 after the federal STC discount of $2,203 (STC Zone 3). That is $7,583–$10,013 before the discount, which the installer takes off the quote.

TierInstalled after STCsPer watt
Budget$4,440–$6,445$0.68/W
Mid-range (most quotes)$5,380–$7,810$0.82/W
Premium$7,051–$10,236$1.08/W

Adelaide runs about 16% below the national average for this size. Full breakdown by size and tier on the Adelaide solar cost page.

How much a 8kW system generates in Adelaide

With 5.0 peak sun hours a day, 18 panels (8kW) in Adelaide produce about 11,388 kWh a year — roughly 31 kWh a day averaged across the year, more in summer and less in winter.

Typical monthly output, Adelaide (Zone 3 profile)
Jan1,252 kWh
Feb1,138 kWh
Mar1,081 kWh
Apr911 kWh
May740 kWh
Jun626 kWh
Jul683 kWh
Aug797 kWh
Sep911 kWh
Oct1,024 kWh
Nov1,081 kWh
Dec1,138 kWh

Using about 40% of that on site at 40c/kWh and exporting the rest at 3.0c saves $1,820–$2,530 a year, for a payback of 2.6–3.6 yrs. Shift the dishwasher, washing machine and hot water into daylight hours and you land at the short end.

Is 8kW the right size for your Adelaide home?

8kW suits families with a pool pump or ducted air-con. As a rule of thumb it matches a quarterly electricity bill of $600–$900 or daily use of 20–28 kWh.

  • Roof space: about 36m² of unshaded roof for 18 × 440W panels, ideally north, or split east/west
  • Inverter: a 6kW inverter; three-phase advised above 10kW
  • Export limits: most SA networks cap single-phase export at 5kW — ask about export limiting or three-phase, or add a battery to soak up the surplus
  • Going bigger: cost per kW falls with size, so if the roof allows, 10kW is often only a little more per month on finance

Not sure? The free Adelaide solar score sizes the system from your bill and household.

8kW solar with a battery in Adelaide

A 8kW array pairs naturally with a 10kWh battery. Adding one costs $6,984–$9,984 after the federal battery discount of $2,516, and shifts about 8 kWh of solar into the evening each day — worth roughly $1,080 a year at Adelaide tariffs. Solar and battery as one job in Adelaide: $12,364–$17,794.

Brand-by-brand installed prices are in the battery guide.

Rebates on a 8kW system in SA

  • Federal STC discount: $2,203 on 8kW in Zone 3 (8 kW × 1.382 × 5 years × $39.85). Deeming drops to 4 years on 1 January 2027, cutting this by about $441.
  • SA: the country's highest electricity prices — which is what makes SA paybacks the shortest.
  • Battery: $252 per usable kWh under the federal Cheaper Home Batteries program.

All SA rebates →

Other sizes in Adelaide and 8kW elsewhere

Other sizes in Adelaide

8kW in other cities

Solar in Adelaide — suburbs, installers and rebates →

8kW in Adelaide: common questions

How much does a 8kW solar system cost in Adelaide?

$5,380–$7,810 installed after the $2,203 federal STC discount, for Tier 1 panels and a quality inverter (October 2026). Premium panels with micro-inverters run to about $10,236.

How many panels is a 8kW system?

18 panels at today's 440W size, needing about 36m² of roof. Older 370–400W panels would mean 21.

How much power does 8kW produce in Adelaide?

About 11,388 kWh a year — 41 kWh a day in the best month and 20 in the worst — on an unshaded north-facing roof.

What is the payback on a 8kW system in Adelaide?

2.6–3.6 yrs, saving $1,820–$2,530 a year at 40c/kWh. A battery lengthens payback slightly but lifts the saving.

Get 8kW quotes in Adelaide

The free solar score checks whether 8kW is the right size for your bill and roof, shows the Adelaide price range, and — only if you ask — shares your enquiry with up to two CEC-accredited local installers. Get my solar score →

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