Solar Panel Calculator for New Zealand

Rooftop solar is a steady, growing choice in New Zealand, with self-consumption plus buy-back from your retailer. This free solar calculator estimates your system size, payback and savings in New Zealand dollars using local rates and sun hours.

Calculate my solar payback in New Zealand →

Solar at a glance in New Zealand

Payback improves the more of your solar you use during the day, given modest export rates.

CurrencyNew Zealand dollars (NZD)
Typical electricity rateNZ$ 0 per kWh
Installed cost≈ NZ$ 3 per watt
Peak sun hours≈ 4.2 hours/day
Export / buyback≈ NZ$ 0 per kWh

Indicative 2026 starting points — every figure is editable in the calculator, and results depend on your own bill, roof and installer quotes.

A typical 5 kW system in New Zealand

At around NZ$ 3 per watt, a 5 kW rooftop system costs roughly NZ$ 15,000 and produces about 5,979 kWh in its first year at New Zealand's 4.2 peak sun hours a day. Your real numbers depend on your roof, shading, panel choice and how much power you use during the day — run your own figures in the calculator to see your exact payback, net savings and ROI.

How the solar calculator works

  1. Your setup. New Zealand and New Zealand dollars are pre-selected, with local electricity rate, install cost and sun hours filled in. Enter your monthly bill, or size the system from your appliances.
  2. Your roof. Search your address or tap “use my location”, then draw your roof on the satellite map — or just type its area. We check the system fits and read local sun hours from NASA data.
  3. Your results. Instantly see your payback period, net savings, ROI, system size, year-1 production and lifetime CO₂ offset — compare cash vs. a loan, and download a PDF report.

Common questions — solar in New Zealand

How many solar panels do I need in New Zealand?

It depends on your electricity use, roof space and local sun hours (about 4.2 peak sun hours/day here). A 5 kW system of high-wattage panels is a common starting point for a home — enter your bill or appliances and the calculator gives your exact panel count and system size.

Does New Zealand have net metering?

New Zealand doesn't use classic net metering — retailers pay a buy-back rate for exported energy that varies by plan, while self-consumed solar offsets your retail price. The calculator models this as buyback.

Are there solar subsidies or incentives in New Zealand?

There is no broad national cash subsidy; the return comes from offsetting retail power and choosing a retailer with a good buy-back rate.

How much does a solar system cost in New Zealand?

A typical 5 kW system is around NZ$ 15,000 at about NZ$ 3 per watt installed. The calculator prices your own size.

Work out your system size

Not sure how big a system you need? These guides work back from your monthly usage:

Solar calculator by country

Open the free solar calculator for New Zealand →