New rules encourage more solar to networks

More solar energy systems – big and small – will soon be able to supply more electricity to local networks, following decisions announced today by the Electricity Authority Te Mana Hiko (Authority).

The Authority is updating rules to make lines companies’ ‘export limits’ more efficient. In most cases, this means electricity generation and storage connected to local networks – such as rooftop solar, batteries, and wind and solar farms – can export more power, while ensuring networks stay within safety and reliability limits.

Authority General Manager Networks and System Change Tim Sparks said over time, more efficient export limits support lower network costs that flow through to consumers’ bills.

“Currently about 75,000 households with solar, and more than 14,700 of those with batteries, can feed into local networks. But the amount of electricity they can supply has been capped at levels lower than it needs to be, which means, at times, higher-cost electricity is being used instead of these cheaper sources of power,” Sparks said.

Under the new rules, lines companies must set a default export of 10kW for straightforward, small-scale distributed generation, such as household solar and battery systems.

“Recent regulatory changes have enabled lines companies to voluntarily increase their export limits for residential connections – and it’s great to see most of them taking advantage of that already. These new rules will ensure all lines companies are setting at least 10kW limits for residential connections where they can – although this won’t be possible everywhere on networks.

“The new rules are important for locking in the progress already made and ensuring any network extensions have export limits that maximise benefits for consumers.

“Following feedback, we’re also allowing lines companies to offer a dynamic or flexible export limit for residential connections, as an alternative to the fixed 10kW limit. This makes the export limit even more efficient. Lines companies will be able to flex above or below the 10kW as conditions on the network change – rather than setting a lower limit that must always apply.

“This flexible approach future-proofs regulations. It opens the door to adopting smarter, more flexible technologies in the future, including vehicle-to-grid charging that returns electricity to the network from EV batteries,” Sparks said.

As part of the changes, industry will be required to develop assessment tools for establishing when a limit below 10kW is needed for safety or reliability reasons, or where a dynamic or flexible limit is appropriate.

The new rules also create a nationally consistent and transparent approach to export limits for solar installations, wind farms and other distributed generation that supply more than 10kW.

“We’re requiring industry to develop an assessment tool for lines companies to use when setting exports for larger-scale distributed generation.

“This will standardise the approach across each of the 29 lines companies and streamline the process for those connecting larger distributed generation to networks. It could also encourage the installation of larger systems, as people will be clearer from the outset about their potential return on investment for exporting electricity,” Sparks said.

The 10kW default export limit for residential connections is required to come into effect later next month with other changes being required at stages through until mid-October. 

This decision is the first part of stage two of the Authority’s broader Network connections project that is making distribution networks more efficient, lowering costs for consumers and improving the security and resilience of the electricity supply.

Future work on this project will consider issues such as application processes for residential solar, rules to enable plug-in solar (‘balcony solar’) and the fees paid for processing applications to connect to the network.

Read the decision paper for more information.