The upper limit of solar you can install on your roof is determined by a few factors (read about sizing your solar system here): the size of your roof of course, as well as the weigh it can support but a less obvious limit is how much the system is permitted to generate and to export to the grid.

Why does a limit exist?

Originally, the electricity network has been designed to work in one direction and provide electricity to the clients. With the number of solar installation increasing, the network has become a two-way system. If not managed correctly, the number of solar installations feeding electricity back to the grid can lead to overvoltage. That’s why distributors now require pre-approval for all solar PV systems.

Solar system capacity limitations  in Victoria

The pre-approval scheme automatically approves solar systems up to 5kW on a single-phase connection as long as they meet a list of requirements. Of course, it is possible to get larger systems approved but the process takes longer.

In Victoria, the pre-approval scheme is the following: (source: www.energy.vic.gov.au/)

Once the approval is accepted, the customer can go ahead with the solar installation and proceed to the connection. The pre-approval assessment can also be approved under the condition to reduce the inverter capacity. In this case, customers can either change the inverter to the approved capacity or request another Technical Assessment. This may result in a different result to the initial assessment.

What about larger solar power systems?

Of course, it is possible to install larger systems but the process takes longer. Note that larger inverter systems require more a detailed assessment and are more likely to require network augmentation and financial contribution from the applicant. For example in the AusNet Services distribution area,  systems from 30kW and up to 1.5 MW require a detailed technical assessment. The total administration fee for projects of that size is $2,200.25 (excl. GST) for systems up to 200kW and $7,600.25 (excl. GST) for systems greater than 200kW and up to 1.5MW. There may be additional fees if grid augmentation is required (such as us having to install extra poles and wires). (source: ausnet.com.au).

Large systems may also require an ‘export limiting’ functionality.

 

Energis provide an end-to-end approach and will organise and complete all required approval. For further information, contact us on 13 782 217 or via email on contactus@energis.com.au