Powerbill/Solar

Is home solar worth it here?

Rough payback estimator for a standard grid-tied rooftop system. Uses current MBIE retail rates and NIWA solar yield data by climate zone. Everything is adjustable.

InputsAdjust to match your quote
1340 kWh/kW/yr · 36.6c/kWh retail
System size6 kW
Total install ~$14,400
NZ average ~7,100 kWh/yr
Self-consumption40%
Share used directly vs exported
What your retailer pays for exports
Battery storage (optional)
Capacity0 kWh
0 = no battery · typical NZ: 10-14 kWh
Battery install ~$0
Round-trip efficiency90%
Typical lithium: 88-92%
Annual saving
$1756
$146/mo average
Payback period
8.2 yrs
Until install cost is recouped
20-year net
+$20,719
After install cost recovered
How the maths works
Annual generation
8,040 kWh
Direct self-use
3,216 kWh
Exported
4,824 kWh
Self-use saving
$1177/yr
Export revenue
$579/yr
Total install
$14,400

Frequently asked

Is solar worth it in New Zealand in 2026?

Payback periods in NZ have fallen from 12-15 years a decade ago to 6-9 years in 2026 as retail rates have risen. Homes that use most of their generation during daylight hours (EVs, daytime heat pumps, home workers) see the fastest payback. Feed-in tariffs for exported power remain modest at 8-17c/kWh depending on retailer.

How much does a home solar system cost in NZ?

Installed cost in 2026 is around $2,000-$2,800 per kW for a standard grid-tied system, or $12,000-$18,000 for a typical 6 kW install. Adding a battery roughly doubles this. The default in this calculator reflects the Consumer NZ and Solar Association 2026 average; adjust to match your actual quote.

What is self-consumption and why does it matter?

Self-consumption is the share of solar generation you use directly rather than export. You save the full retail rate (~35-45c/kWh) on self-consumed power but only the feed-in tariff (~8-17c/kWh) on exported power. Running your dishwasher, hot water, EV and pool pump during daylight hours is the single biggest driver of solar economics.

What solar yield should I use for my region?

This calculator uses NIWA SolarView averages by climate zone: 1350 kWh/kW/yr for Auckland and the upper North Island, 1280 for Wellington and top of the South, 1340 for Canterbury, and 1200 for Otago and Southland. Actual yield depends on roof pitch, orientation, shading and panel quality.

Is a battery worth adding to a solar system?

A battery lets you use your own solar in the evening instead of exporting it for 12-15c and re-buying it back from the grid at 35-45c. The economics are driven by the spread between your retail rate and the feed-in tariff: a ~10-14 kWh battery costs $10,000-$17,000 installed in NZ and typically adds 2-4 years to payback on a panels-only system. Standalone, batteries rarely pay back before their ~10-year warranty ends, but they do add resilience during outages (if installed with a backup circuit) and lock in your evening power cost.