Solar payback calculator
Enter your power bill and region to see which system size fits, how much it saves a year and how long it takes to pay back. Every assumption is shown and you can change it. Payback is the installed price divided by the yearly saving.
- Your yearly use
- 7,389 kWh
- Generated
- 7,000 kWh
- Used at home
- 4,200 kWh
- Exported
- 2,800 kWh
- Saving a year
- $2,041
- Typical price
- $11,000–13,000
How to read the result
The biggest lever is the share of solar you use at home, because it saves about 40.6c a kWh while exports earn 8c to 24c. Move the slider to see it. See is solar worth it in NZ for the full explanation.
Sources
- Canstar NZ citing MBIE Quarterly Survey of Domestic Electricity Prices to 15 Feb 2026 (checked Feb 2026)
- Solar Scout, How many solar panels do I need (updated 1 Apr 2026) (checked 1 Apr 2026)
- Solar Scout, Buy-back rates NZ (updated 31 Aug 2026) (checked 31 Aug 2026)
- Solar Scout, Solar panel costs NZ (checked Sept 2026)
How does the calculator work out payback?
It sizes a standard package from your yearly kWh and your region's output per kW, splits the generation into solar used at home (saving your price per kWh) and solar exported (earning your buy-back rate), and divides the typical installed price by the yearly saving.
Where do the default numbers come from?
40.6c per kWh is the MBIE average household price to February 2026. Output per kW, the 60% self-use share and the 12c buy-back rate are from Solar Scout's 2026 guides. Package price ranges are Solar Scout's 2026 figures.
Why doesn't it ask about roof direction?
We haven't found a published NZ loss factor we'd stand behind, so we don't guess one. The site survey or a solar report measures it for your roof.
Is the result a quote?
No. It's an estimate on published figures. General information, not financial advice.
See your fixed price in two minutes.
Tell us about your roof and your power bill. You get the recommended package, the price and the payback maths, with every assumption listed.