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.
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.
Guide to Connecting Distributed Generation to the MainPower Network
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.
Electricity (Safety) Regulations 2010 (particularly part 5)
AS/NZS 3000:2007 (this standard can be purchased from Standards New Zealand)
- Note: AS/NZS 3000:2018 has not been fully gazetted in New Zealand. While the 2018 edition was published, the Electricity (Safety) Regulations 2010 still cites AS/NZS 3000:2007. This means the 2007 standard, including its amendments, is the standard that must be used for compliance with the regulations until the regulations are updated.
- Note: AS/NZS 3000:2018 has not been fully gazetted in New Zealand. While the 2018 edition was published, the Electricity (Safety) Regulations 2010 still cites AS/NZS 3000:2007. This means the 2007 standard, including its amendments, is the standard that must be used for compliance with the regulations until the regulations are updated.
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 4777.1:2016
AS/NZS 4777.2:2020
AS/NZS 3000:2007
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.
No change to export limits
In order to maintain network stability and reliability MainPower will not increase export limits at this stage. Increasing export limits could cause voltage issues for other customers, especially in our radial network configuration where voltage balancing is more complex.
MainPower will continue collaborating with the wider industry and will review this position, providing updates to customers and installers if any changes occur.
Additional Resources:
- Government Announcement – MBIE: mbie.govt.nz
- Electricity Authority Statement: ea.govt.nz
- AS/NZS 4777.1:2016 Standard: https://www.standards.govt.nz
No. While the allowable voltage range has increased, MainPower is not changing export limits. The wider range improves overall hosting capacity across the network, enabling more customers to install solar – not necessarily allowing individual customers to export more.
Our network is geographically large with fewer connections per kilometre of line. Unlike urban networks, we must carefully manage voltage swings caused by seasonal load changes and distributed generation. Increasing export limits could risk destabilising the network.
Non-compliant systems must be disconnected immediately. All installations must meet the standards and be approved by MainPower. Your electricity supply may be withheld until this system is disconnected (refer section 3.5 of Network Connection Standards and section 7.4 and section 9.5 of the Standard Connection Agreement).
You can still install solar, but your export limit will be capped at 5 kVA for single-phase systems. 3 phase connections will be assessed on a case-by-case basis but must not have an imbalance of more than 5 kVA between phases. We recommend working with trusted local installers who understand our network requirements.
Export constraints & curtailment
The following 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
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We’re here to help
If you need some assistance or advice, please get in touch with our team.