Solar Power Generated in New Zealand

How much solar power can we generate here in New Zealand?

The volume of electricity solar power systems produce relies on the intensity of the sunlight and the amount of clear sunny days you have; 

  • The intensity will vary depending on your location. The sun is more intense the further north you go.
  • Clouds affect how much power the system generates, on a cloudy day there will still be power generated but it will not be at optimal output.

Below is a solar radiation map of New Zealand, showing areas that experience the most sun light in a given day.  Locations with a higher proportion of clear-sky days such as Nelson, Blenheim, Manawatu, Bay of Plenty, and Hawke’s Bay correlate with higher solar irradiance. The more Northern parts of New Zealand benefit from higher sun angles.

Solar Radiation New Zealand
Resource from NIWA Science

Solar in NZ compared to the world

Installing a solar power system is worthwhile for all areas of New Zealand.  Invercargill get’s a lower proportion of sun hours and intensity compared to other parts of New Zealand. However, Invercargill gets more sun than Germany, which is one of the world’s top solar power installers, with almost as much installed solar power systems as the rest of the world combined.

Interestingly, you will see a solar power system produce the most amount of power when the sky is partially cloudy and direct sunlight is hitting the solar panels, as well as sun bouncing off the clouds and then hitting the panels. 

Helpful hint: When you get a quote, ask companies how much power you will generate from the solar power system size that you have been quoted for.

Main Regions Annual Solar Generation Chart for Different Sized Systems

The chart below indicates the approximate annual energy production of different size systems ranging from a 1.6kW system to an 8kW in Auckland, Wellington, Christchurch and Dunedin.  This data is collected from SMA's Sunny Design Web.

energy production chart for new zealand

Wellington Solar Power System Performance Chart

Below is a chart indicating what a solar power system should perform at different with different tilt angles and alternate orientations from north. The different orientation performance ratings are the same for east or west.  The information in this chart has been sourced from NIWA.

The chart indicates the optimal solar panel position for people living in Wellington is 25° from flush and directly north facing.

Wellington Solar Power Performance

An example using this chart: If solar panels are placed on a roof with a 30° pitch and roof is facing 40° west, then the system will perform at 92.2% of the amount it could perform at the optimal position.