Solar & distributed generation
Distributed generation is the equipment used by customers to generate their own electricity (for example, solar panels). Connecting distributed generation to the MainPower distribution network allows customers to sell any excess power generated back to their retailer.
Anyone who meets the applicable safety, technical, operational, and commercial requirements can connect to the MainPower network. MainPower now approves up to 10kW for single phase installations. Three phase installations are assessed on a case by case basis.
We recommend that before you submit your application, you make contact with our Network Services Representative team to discuss your needs (0800 30 90 80 or nsr@mainpower.co.nz).
We recommend having an electrician/installer fill out the forms.
A good understanding of electricity is required to successfully complete the forms. We recommend that you ask your electrician or installer to complete this form on your behalf.
Apply for a solar/distributed generation connection
Click below to get started.
Are you looking for a solar/distributed generation connection?
For example, your property’s power will be generated by wind, solar, thermal or hydro power.
Relevant documents
Here are some links to information and agreements you might need when you’re applying.
Link to guidance from the Energy Efficiency & Conservation Authority Te Tari Tiaki Pūngao
Make sure you read our Connection Agreement, which outlines our relationship and roles and responsibilities when you connect to our network.
Users of our network must comply with our Network Connection Standards.
Part 6 of the Electricity Industry Participation Code 2010 sets out information regarding connecting distributed generation.
Even if your generation will not connect to MainPower’s network (either directly or as part of a mains-connected installation) it will still need to comply with the following requirements.
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Electricity (Safety) Regulations 2010 (particularly part 5)
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Electricity (Safety) Amendment Regulations 2025
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AS/NZS 3000:2018 (this standard can be purchased from Standards New Zealand)
Inverters
If you are connecting through an inverter you will also need to comply with the following standard:
- AS/NZS 4777.2:2020
Read the full list of approved inverters here.
For more information on standards, visit Standards New Zealand or SAI Global. Please note that you will be required to purchase standards.
When connecting generation to the MainPower network, the following technical standards apply:
AS/NZS 5033.2012
AS/NZS 4777.1:2024
AS/NZS 4777.2:2020
AS/NZS 3000:2018
Changes to solar power regulations – what it means for you
Overview
In June 2025, the New Zealand Government announced a change to the Electricity Regulations that expands the allowable low voltage supply range from 230V ±6% to 230V ±10%. This means electricity distributors like MainPower can now operate networks within a wider voltage range: 207V to 253V, instead of the previous 216V to 244V.
This change is designed to support the growing adoption of rooftop solar, home batteries, and EV chargers, while helping to reduce unnecessary curtailment and defer costly network upgrades.
What does this mean for solar customers?
Improved performance
Inverters installed after this change will be less likely to reduce exports due to voltage constraints. With more headroom in the voltage range, inverters can operate more efficiently and are less likely to shut down due to over-voltage situations.
Vehicle‑to‑Grid (V2G)
Additional Resources:
- Government Announcement – MBIE: mbie.govt.nz
- Electricity Authority Statement: ea.govt.nz
- AS/NZS 4777.1:2024 Standard: https://www.standards.govt.nz
If you can’t find the answers you need please get in touch with our team.
Export constraints & curtailment
Generation export may be curtailed at times to maintain safe network operation (e.g. periods of low demand or high generation).
MainPower encourages customers to maximise self consumption where practical.
The following known export constraints are currently in place. If you think your application will be affected by these constraints, please get in touch with our Network Services Representative team to discuss your options.
Mt Cass Road – east of the confluence of Omihi Creek and the Waipara River.
MainPower reserves the right to interrupt the connection of any Distributed Generation to the Network, or curtail either the operation or output of Distributed Generation, or both, and may temporarily disconnect the Distributed Generation from the Network under the following circumstances:
(a) Whenever MainPower deems it reasonably necessary for planned maintenance, construction, or repairs on the network.
(b) In emergency situations or for the purpose of protecting or preventing danger or damage to persons or property.
(c) If the Customer modifies its Distributed Generation without obtaining prior authorisation from MainPower, and such modification has a material effect on the injection of electricity from the Distributed Generation into the network.
(d) As a consequence of obligations imposed on MainPower that, in MainPower’s opinion, could affect the operation of the Distributed Generation. This includes obligations imposed by Transpower New Zealand Limited, both as the owner of the National Grid and as the System Operator, obligations to an electricity retailer, or obligations arising in respect of other distribution networks, or imposed by law, including the Electricity Industry Participation Code 2010.
(e) In the case of a prevalence or saturation of DG installations on any part of MainPower’s Network leading to operational issues, including but not limited to excessive voltage or compromising of protection equipment or settings.
When connecting generation to the MainPower network, the following technical standards apply:
AS/NZS 5033.2012
AS/NZS 4777.1:2016
AS/NZS 4777.2:2020
AS/NZS 3000:2007
Distributed Generation FAQs
If you can’t find the answers you need, please get in touch with our team.
MainPower applies network pricing and connection arrangements at an individual ICP (Installation Control Point) level. Any financial allocation of generation across multiple ICPs would generally be a retailer settlement arrangement and does not change how network charges are applied to connected ICPs.
Yes. Network charges are based on the physical connection and energy flows associated with individual ICPs. Financial or virtual allocation arrangements between a customer and retailer do not alter the application of standard network charges.
No. MainPower does not currently apply reduced network charges based on the geographic proximity of generation and consumption within the network.
Standard distributed generation connection processes and assessments apply. Depending on the nature and scale of the proposal, connection-related fees or charges may apply.
In most cases, existing ICPs remain on the applicable network tariff. However, changes to connection capacity, site configuration, or tariff eligibility may result in a review of the applicable pricing category.
Potentially. Tariff eligibility depends on factors such as connection capacity, load characteristics, and export capability. Any tariff classification would be assessed as part of the connection application process.
MainPower’s network charges and connection arrangements are based on physical ICPs. Customers considering virtual allocation or multi-ICP settlement arrangements should discuss the commercial and settlement aspects with their electricity retailer.
All distributed generation installations must comply with applicable industry requirements and MainPower’s distributed generation connection process. Depending on the proposal, technical assessments may be required to evaluate factors such as network capacity, protection requirements, voltage impacts, and export limits.
We encourage customers, developers, and installers to engage with MainPower early in the project planning process. Early engagement helps identify network requirements, technical considerations, and connection options before detailed design work begins.
We’re here to help. Get in touch if you need help. Or, check out our FAQs.
We’re here to help
If you need some assistance or advice, please get in touch with our team.