Proposals to expand the permitted voltage range for electrical supply

About the consultation

Most homes and businesses in New Zealand connect to the electricity system through low voltage distribution networks and the electricity is delivered to most households at 230 Volts. Regulations required electricity on these networks to be supplied within a range of +/-6% (except for momentary fluctuations). Voltage typically falls when power consumption increases and rises when electricity generation increases.

The pattern of power flow on low voltage networks is changing as more homes and businesses invest in distributed energy resources (DER), like rooftop solar photovoltaic panels (solar PV). Solar PV can make valuable contributions to the power system and household bills. However, to keep voltages within the regulated limit, networks would need to either curtail the output from solar PV or invest in significant network upgrades, which would result in higher bills for consumers. Expanding the voltage range enables electricity networks to accommodate more DER and allow the rooftop solar owners to export more electricity back to the network.

This also better aligns New Zealand with Australia and countries in Europe (depending on the option chosen). The standards for appliances sold in New Zealand already require appliances to work with a wider range of supply voltage. 

The Ministry of Business, Innovation and Employment (MBIE) consulted on two proposals:

1. Expanding only the upper voltage range from +6% to +10%
2. Expanding the upper and lower voltage range from +/-6% to +/-10%.

The discussion paper sought feedback on:

• The benefits of expanding the upper and/or lower voltage limits
• The risks to appliances from expanding the upper and/or lower voltage limits
• Any particular appliances that were at higher risk of failing from expanding the voltage range
• Whether changes to the voltage range should be phased-in
• The potential costs of expanding the voltage range
• Any other regulations or standards that would need updating if the voltage range was expanded.

Submissions for the consultation closed 29 November 2024, 5pm. 

Next steps

The Government expanded the permitted voltage range to +/-10%. The regulatory changes that give effect to Cabinet’s decision were approved as part of its updates to 440 out of date citations of standards across the electricity and gas sector. 

You can learn more about the changes to the regulations on the Energy Efficiency and Conservation Authority’s website:

Government approves regulatory changes to boost energy efficiency and solar uptake(external link)

Minister's release

Supercharging residential solar power generation(external link) – beehive.govt.nz