Western Power connection rules effective July 1st 2025.

Many people aren't sure whether their home has single phase power or three phase.
If you can see three fuses under (or over) your meter and your 'Main Switch' is 3 poles wide
as shown in the picture below, then you have 3 phase supply. If not, it's single phase.


The Western Power/Synergy table above explained.
I'll use 'kW' instead of 'kVA' as it is the term more people are familiar with.

For the purposes of this explainer the two terms are interchangeable.

Single phase
You can install up to 10kW of 'solar only' inverters.
That might be 2 x 5kW inverters or 1 x 10kW inverter.

Or you can install up to 10kW of battery inverters that can also connect solar.
That might be a 10kW hybrid inverter, solar panels and a DC Coupled battery connected to that inverter.
Or it might be a 5kW hybrid inverter, solar panels and battery and a 5kW AC Coupled battery.

However the TOTAL of all of these cannot exceed 15kW.

Therefore you could have a 10kW 'solar' inverter, solar panels and 5kW battery inverter.
Or you can have a 5kW solar inverter, and 2 x 5kW AC Coupled battery inverters.
Or a 5kW solar inverter and a 10kW hybrid inverter and batteries.

It's very generous and for almost everyone, exactly what they want.
There are some that will miss out though.
Someone who has 2 x Tesla Powerwall 2 battery inverters can only add a 5kW solar inverter.

See section at the end about export limiting that applies to single and three phase.

Three phase
You are allowed 15kW of solar inverter(s).
You are allowed 15kW of battery inverters, AC or DC Coupled.
In total you can't have more than 8kW per phase.

I'll unpack that with a couple of examples.

You install a 15kW 3 phase hybrid inverter, solar panels and a DC Coupled battery.
That's fine. 5kW per phase.

You have a 8kW 3 phase inverter with solar already and add the above 15kW inverter.
That's 8 + 15 = 23kW in total, or 7.66kW per phase. Fine as well...but only just.

Export limiting.
This is where things may get VERY messy indeed.
The most important factor here is Synergy.
Are they going to increase the inverter limit for feed-in tariffs from 5kW to 10kW or 15kW?

If not then anyone with inverters totalling more than 5kW will need to export all of them to 1.5kW.
There will be no payment on that 1.5kW as is currently the case.

If Synergy do change their 5kW limit then export limiting will be set to 5kW.
So a 10kW inverter will be export limited to 5kW, with a DEBs payment on that 5kW.

This is really going to put the cat amongst the pigeons for people wanting to mix brands.
Let us imagine Synergy don't change the 5kW limit for off-take agreements or feed in tariffs.
Let us say someone has a 5kW three phase Fronius Symo inverter and panels.
They don't want to throw it away but they do want to add a battery.
They install a Sigenergy 5kW hybrid inverter and battery, AC Coupled.
That means the total inverter capacity is 10kW.
The whole must be export limited to 1.5kW
The Sigenergy cannot control the export limit of the Fronius.
Which means the Fronius must be export-limited with it's own meter costing something like $600.
Dear reader, you may or may not understand the above, but I can assure you, it opens a huge can of worms.