Savings calculator · Worked example

Solar and battery for a $1400 quarterly power bill in Western Sydney

For a typical household paying $1400 a quarter in Western Sydney (2150), the system that pays back best is 9.98 kW solar + 29 kWh battery: $11,792 after rebates, about $5,169 saved in the first year, paid for itself in 2.2 years and $48,875 ahead after ten. Worked out 26 October 2026 on current prices, rebates and electricity plans.

Work it out for your own bill

The three worth comparing

Best over ten years

9.98 kW solar + 29 kWh battery

21 × JA Solar DeepBlue 4.0 Pro 475W N-Type Double Glass Monofacial (JAM54D40-475/LR) + ESY 30.7kWh 10kW 1-phase

Price after rebates
$11,792
Saving in year one
$5,169
Pays for itself in
2.2 years
Ahead after 10 years
$48,875

On COVAU PTY LIMITED · SolarMax NSW Endeavour Residential TOU, plan checked 26 October 2026

Solar only: the lowest outlay

6.65 kW solar

14 × JA Solar DeepBlue 4.0 Pro 475W N-Type Double Glass Monofacial (JAM54D40-475/LR) + Kstar All in One 5.0kW Single Phase Hybrid Inverter

Price after rebates
$4,212
Saving in year one
$2,702
Pays for itself in
1.5 years
Ahead after 10 years
$28,098

On Tango Energy · Everyday Easy, plan checked 26 October 2026

Another battery to compare

4.75 kW solar + 35 kWh battery

10 × JA Solar DeepBlue 4.0 Pro 475W N-Type Double Glass Monofacial (JAM54D40-475/LR) + GoodWe 36kWh 10kW 1-phase

Price after rebates
$13,728
Saving in year one
$4,999
Pays for itself in
2.7 years
Ahead after 10 years
$46,057

On COVAU PTY LIMITED · SolarMax NSW Endeavour Residential TOU, plan checked 26 October 2026

How this was worked out

  • A $1400 quarterly bill, turned into daily use at typical NSW rates for postcode 2150.
  • A typical household's day: no answers about pools, air conditioning or an electric car. Yours can change the answer, so the calculator asks.
  • Every system size the roof and the grid connection allow, with and without each battery we install, priced after the federal battery rebate and solar STCs.
  • Each system on the retail plan that saves it the most, from every plan published for the postcode.
  • Installed by Sunbridge Energy NSW. An estimate, not a quote: a site inspection and your real bill give exact figures.

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