Skip to content

Cluster Rule for generators

What’s the Cluster Rule for Generators?

The ‘Cluster Rule’ is the process of aggregating individual generation units at a site as part of the application process, so we can determine the total network and customer impact. In this context, a site refers to a collection of dwellings, often behind a common network connection point. These typically occur within privately owned distribution networks, such as is the case in many retirement villages, aged care, community and strata titled properties. 

Why are Generators Clustered?

  • To assess the impact of generating units connected at a common point on our distribution network.
  • To identify any adverse impact on existing network customers. 
  • To determine the necessary network upgrades to support the generating units.

Exemption for Central Protection

In response to ongoing SA Power Networks and industry feedback on central protection requirement as specified in AS/NZS 4777.1:2016, the Office of the Technical Regulator (OTR) has recently provided a further extension of the standing exemption to Central Protection requirements in certain conditions. This simplifies the connection process for customers in networks that share a common connection point such as retirement villages, aged care, community and strata title. The exemption to the standard includes the following conditions:

  1. The combined inverter generating systems nameplate at the connection point does not exceed 200 kVA;  
  2. The installation is a multiple electrical installation comprised of either multiple residential or commercial premises that are separately occupied or owned by different persons or corporate entities
  3. Where the new inverter energy system (IES) is proposed to be connected to a separately occupied or owned portion of the electrical installation, the IES does not exceed 30 kVA; and 
  4. Each separately occupied or owned portion of the electrical installation has its own independent revenue metering arrangement in accordance with relevant rules.

For generator connections at locations where the connection point exceeds 200kVA of combined inverter-based generation, the discretion and authority to exempt customers from Network Protection requirements rests with SA Power Networks.

Information booklet

Click the button below for to download the Cluster Rule for generators booklet with more information and examples of each configuration.


Flexible Exports trial for clustered Small Embedded Generators (SEG)

When a SEG application is lodged for a clustered site where the total installed capacity exceeds 30kVA, the total site generation is assessed under the Medium Embedded Generation (MEG) application process. This is necessary because individual small generators aggregated at a site have the same collective impact as a single large generator.

We have been hearing from industry that undergoing a MEG assessment for a case like this is a high barrier to entry for a residential SEG application. In response, we have investigated how Flexible Exports could manage the network impacts, mitigate the need for the upfront assessment and enable fairer access to export. To that end, we have launched a Flexible Exports trial for clustered SEG applications from 1 July 2023.

Read more about the Flexible Exports trial for clustered SEG

Note: Individual customers within Embedded Networks are not eligible to opt in for the Flexible Exports trial. Embedded Networks are privately owned electricity network behind a single parent meter, which are common in apartment buildings and retirement villages. Some customers in these networks may have a 'child' energy meter and a contractual agreement with another network service provider who manages this privately owned electricity network. Given that they do not have a direct contractual agreement with SA Power Networks, we cannot offer a Flexible Exports option as a form of network connection agreement. We also have no visibility of the network beyond the parent meter which makes it difficult to implement the service.