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13kW Solar System Australia 2026

Guide to 13kW solar system cost and output in Australia 2026. The largest common residential system — ideal for high-usage homes, EVs, and all-electric properties.

Panels

30–36

Daily Output

45–58 kWh

Cost After STCs

$7,500–$13,500

Annual Savings

$2,600–$4,200

Payback Period

3–5 years

Roof Space

65–80 m²

Ideal for: Very high usage homes, all-electric properties, EV owners, home businesses, or anyone wanting maximum generation.

Is 13kW Overkill?

Not if your usage justifies it. All-electric homes (no gas connection), EV owners, and properties with pools, ducted A/C, and home offices can easily consume 30+ kWh per day. At 45–58 kWh daily generation, a 13kW system covers this and more. Even if you're over-generating now, future loads (EVs, battery, heat pump hot water) will soak up the excess.

How Much Power Does a 13kW System Produce?

Expect 45–58 kWh per day depending on location — that's equivalent to running a large household entirely from solar during daylight hours. Annual output of 16,000–21,000 kWh is roughly 2–3x the average household consumption. Combined with a 13.5kWh battery, some homes achieve 80-90% grid independence.

Cost and ROI

A quality 13kW system costs $10,500–$17,000 before STCs, dropping to $7,500–$13,500 after. Despite the higher absolute cost, the return on investment is often better than smaller systems because the per-kW cost is lowest at this scale. In high-tariff states like SA, payback can be under 3 years. Adding a 13.5kWh Tesla Powerwall or similar battery ($9,500–$13,000) extends payback but dramatically increases self-consumption.

Network Approvals and Export Limits

Systems above 10kW may trigger network pre-approval requirements from your local distributor (Ausgrid, Jemena, Energex, etc.). Some networks impose export limits (typically 5kW) regardless of system size. Your installer should handle the application, but expect 2–6 weeks for approval. In some areas, zero-export limiting may be required — this caps how much power you can send to the grid. A battery helps maximise value in these situations.

13kW System — Cost & Output by State

StateDaily OutputCost After STCsAnnual Savings
QLD57 kWh/day$7,500–$12,000$3,200–$4,200
NSW51 kWh/day$8,000–$13,000$2,900–$3,800
VIC44 kWh/day$6,500–$11,000$2,400–$3,200
SA55 kWh/day$7,500–$12,000$3,600–$4,600
WA59 kWh/day$7,200–$11,500$3,000–$3,800
TAS39 kWh/day$8,800–$13,500$2,000–$2,800

ADVANTAGES

Maximum residential generation for the highest possible savings

Best $/kW ratio — lowest cost per kilowatt at scale

Ideal for EV charging (covers 15,000–20,000 km/year)

Pairs perfectly with 13.5kWh battery for near self-sufficiency

Maximum STC rebate value

Future-proofs against rising electricity prices and new loads

CONSIDERATIONS

Highest upfront cost of residential systems

Requires 3-phase power in most cases

Needs 65–80m² of unshaded roof — not all homes qualify

May require network pre-approval (check with distributor)

Generates significant exports — wasted without battery or TOU optimisation

Find out if a 13kW system is right for your home — takes 60 seconds.

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RELATED GUIDES

Solar Panel Costs 2026 →Battery Guide →All Rebates →Inverter Guide →

Frequently Asked Questions

How much does a 13kW solar system cost in Australia?

A 13kW solar system costs approximately $7,500–$13,500 after federal STC rebates in 2026. Exact pricing depends on your state, panel brand, inverter choice, and installer. Premium tier-1 panels may add $1,000–$2,000 to the base price.

How much electricity does a 13kW system produce?

A 13kW system produces approximately 45–58 kWh on average. Output varies by location — Perth and Darwin get more sun than Melbourne or Hobart — and by roof orientation. North-facing roofs in Australia produce the most energy.

How much will I save with a 13kW solar system?

Typical savings with a 13kW system are around $2,600–$4,200 per year, depending on your electricity rate, usage patterns, and how much solar energy you self-consume versus export to the grid. Adding a battery increases self-consumption from ~35% to ~70%.

How many panels are in a 13kW system?

A 13kW system typically uses 30–36. Most modern panels are 400–440W each. You'll need approximately 31 panels at 420W to reach 13kW. Your installer will confirm exact panel count based on the brand selected.

Is a 13kW system big enough for my home?

That depends on your electricity usage. Check the "Ideal For" section above for detailed household profiles. As a rule of thumb: divide your quarterly bill by $150 to estimate the kW you need. Our free solar score tool gives you a personalised system size recommendation.