Solar Export Limits NZ: 10kW Code Rules & Dynamic Export

Key Takeaways

• On 11 May 2026, the Electricity Authority mandated 10kW as the default residential solar export limit across New Zealand.
• Roughly 75,000 New Zealand homes feed solar back to the grid, including more than 14,700 with a battery.
• Twenty-six of the thirty national lines companies provide a flat 10kW export threshold without complex dynamic throttling.
• Vector in Auckland launched dynamic export connections up to 10kW, requiring CSIP communications and a fail-safe 2.5kW fallback.
• All new inverters must be configured to AS/NZS 4777.2:2020 'Australia A' settings with allowable voltage operating range expanded to 230V +/- 10%.

The 10kW Code amendment: what changed on 11 May 2026

For over a decade, most New Zealand lines companies (Electricity Distribution Businesses or EDBs) capped single-phase solar export at 5kW. Homeowners who installed 6kW to 10kW arrays faced harsh export throttling, with excess solar electricity clipped and wasted.

On 11 May 2026 the grid made 10kW the default for solar export. The Electricity Authority enacted the Export Limits Code amendment under Part 6 of the Electricity Industry Participation Code 2010. Lines companies cannot restrict export below 10kW unless they prove localized transformer congestion through formal network studies.

Roughly 75,000 New Zealand homes already feed solar back, more than 14,700 with a battery. The reform provides regulatory certainty for homeowners sizing modern solar arrays.

Check lines company submission workflows in distributed-generation-application-lines-company-nz.

National lines company scorecard: flat vs dynamic export

Twenty-six of the thirty lines companies now give you a flat 10kW. However, approaches vary across major metropolitan networks:

Vector's dynamic export architecture

Vector opened its dynamic export connections on 11 May 2026, single-phase, up to 10kW. Rather than hard-capping output, Vector uses digital communication to monitor feeder voltages.

Your inverter must meet AS/NZS 4777.2, be CSIP capable (Common Smart Inverter Profile, the protocol that lets Vector communicate with it), and be online. If your inverter's connection drops out (such as a home WiFi outage), it falls back to a fixed 2.5kW until it reconnects.

Wellington Electricity's pricing framework

In Wellington, the distributor took a tariff-based approach: rather than set a fixed limit (10kW), they use a price signal to DG owners to lower injection back to 5kW when parts of the network become congested. Furthermore, from 1 April 2026 it brought in a regulated rebate for exports during the winter peak periods for smart meter customers.

Technical inverter and grid standards

To maintain grid stability under higher distributed generation injection, national standards lock in specific inverter operating envelopes:

1. Mandatory voltage profile: Inverters must meet AS/NZS 4777.2:2020 using 'Australia A' settings, alongside AS/NZS 4777.1:2024 installation guidelines.
2. Expanded operating voltage: The allowable voltage operating range at the customer point of connection has been expanded to 230V +/- 10% to accommodate solar voltage rise during peak midday hours.
3. Compliance timeline: On 11 September 2026 distributor inverter-compliance requirements begin across all lines companies.

Sizing your system under the 10kW cap

A 10kW export limit allows homeowners to install a 10kW AC inverter paired with up to 12kW of DC panels. This oversized array maximizes solar yield during morning and winter periods without violating grid injection thresholds.

Review system sizing calculations and self-consumption economics in solar-system-sizing-self-consumption-new-zealand, and explore retailer buyback tariffs in solar-buyback-rates-by-retailer-new-zealand.