Distributed Generation Application NZ: Lines Company Solar Guide

Key Takeaways

• Connecting rooftop solar in New Zealand is legally governed by Part 6 of the Electricity Industry Participation Code 2010.
• Once approved, residential solar grid connections are governed under statutory regulated terms set out in Schedule 6.2.
• Connections require your property's unique 15-digit Installation Control Point (ICP) number.
• Network approvals take 10 to 30 working days depending on whether your inverter appears on the distributor's approved list.
• New Zealand lines companies transitioned to a default 10kW single-phase export limit from 11 May 2026.

What is a Distributed Generation application?

In New Zealand electricity terminology, any system that generates power on site and connects to the local electricity distribution network is classified as distributed generation (DG). This encompasses residential rooftop solar arrays, domestic battery storage units, and micro-wind installations.

Rooftop solar cannot be legally plugged into your switchboard without formal network approval. The application and approval process between the prospective generator and the distributor is mandated under Part 6 of the Electricity Industry Participation Code 2010. The Electricity Authority monitors compliance across the country's 29 Electricity Distribution Businesses (EDBs), commonly known as lines companies (such as Vector, Powerco, Orion, and Wellington Electricity).

Understand how network applications fit into the broader project timeline in our complete solar-panel-installation-process-new-zealand.

Step-by-step lines company approval workflow

While your certified solar installer files the paperwork, understanding each step ensures your project progresses without unnecessary administrative delays:

Identifying your ICP number

Every grid connection in New Zealand is identified by a unique 15-digit Installation Control Point (ICP) number. Found directly on your monthly retail electricity bill, this number pinpoints the exact service line and transformer feeding your property. Powerco, Vector, and all regional EDBs use this identifier to cross-reference network circuit capacity.

Approval timeframes: pre-approved vs non-approved inverters

If your system utilizes an inverter from your distributor's pre-approved register, approval is typically issued within 10 business days. If the inverter is not on the list or involves non-standard configurations, engineering review can take up to 30 business days. Powerco notifies installers within 5 working days if an application lacks necessary technical documentation.

Technical grid standards and inverter voltage settings

All distributed generation inverters connected to New Zealand networks must meet strict grid-protection standards:

• AS/NZS 4777.2 compliance: Inverters must comply with AS/NZS 4777.2 grid connection standards. Vector and national lines companies recommend the AS/NZS 4777.2:2020 'Australia A' voltage profile settings for all new installations.
• Allowable voltage range: The allowable operating voltage range at the customer point of connection has been expanded to 230V +/- 10% to prevent localized overvoltage tripping during peak midday export windows.
• CSIP communication protocol: To qualify for dynamic export schemes, inverters must support the Common Smart Inverter Profile (CSIP) protocol, enabling remote communication with distribution management systems.

The 10kW single-phase export limit

Historically, lines companies restricted residential solar exports to 5kW per phase. Under modernized network standards implemented on 11 May 2026, lines companies including Vector and Powerco lifted default single-phase export limits to 10kW.

This allows homeowners to install systems up to 10 kW without suffering heavy export curtailment. For an in-depth review of dynamic network throttling, see our guide on solar-export-limit-10kw-dynamic-export-nz.

Contract terms and post-installation compliance

Once approved, your connection is governed by the statutory regulated terms in Schedule 6.2 of the Code alongside the distributor's congestion policy.

Following physical installation, your electrician must carry out electrical testing and issue a Certificate of Compliance (CoC) referencing compliance with AS/NZS 4777.1 and AS/NZS 3000. Under lines company rules, this CoC must be submitted to the distributor within 10 working days after installation. Check installer quoting standards in our guide to how-to-read-solar-quote-new-zealand.