According to the authority (EA), some 25 of 30 networks already offer this, another four are getting there and only one isn’t considering it.

“However, we wish to mandate the default to ensure national and ongoing consistency.”

Perhaps more significant is that the EA is using the mandate to introduce mandatory standards for export limit measurement and calculation to “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,” the EA said in a statement.

“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," said Tim Sparks, the EA’s general manager for networks and system change.

The changes will allow distributors to “offer dynamic or flexible export limits as an alternative to the static 10kW default”.

“Dynamic or flexible limits would allow [distributed generation] export at maximum system capacity (eg, at times above 10kW) when there are no constraints on the network and reduce exports when required.

“This means distributors would only need to limit exports for the periods the network is constrained, rather than applying ‘blanket’ lower limits that always apply,” the authority said.

Some 75,000 households with solar, and more than 14,700 of those with batteries, can currently feed into local networks.

However, capping below 10kW meant that “at times, higher-cost electricity is being used instead of these cheaper sources of power," Sparks said.

The rule changes also include updated inverter standards and settings.

Future work would “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”.

The 10kW default export limit for residential connections comes into effect in late May and other changes will occur at stages until mid-October.