Yes, you can install a single-phase inverter on a three-phase home.  It is a good solution because you get the full value of your solar generation across all three phases, and you don’t have to pay for a more expensive three-phase inverter.

The reason why a single-phase inverter works on a three-phase home is because of net metering.

In this post we answer these questions:

• What is net metering?
• How does net metering work with a single-phase inverter on a three-phase home?
• How can you tell if your home is three-phase?
• When should I get a three-phase inverter?

What is net metering? 

It is correct that a single-phase inverter will only send electricity to one of your home’s three phases.  But from your point of view, this doesn’t matter.  Because of net metering, you will still receive the full value of your solar generation across all three phases regardless of whether you have a single-phase inverter or a three-phase inverter.

With net metering, your grid imports and grid exports are recorded and calculated across all three-phases – they are not calculated separately.

For example, if your system is exporting 4kWh on one phase, but importing 1kWh on each of the other two phases do you have to pay for the 2kWh of grid imports?  (This is an important question because the price of grid imports is much higher than what you are paid for grid exports).

The answer is no, you don’t pay for the 2kWh of grid imports.  That’s because the net meter calculates the sum of your grid imports (i.e. 2kWh) and subtracts that from the 4kWh of grid exports as follows:

Grid exports: 4kWh – Grid imports: 2kWh = Net result: 2kWh of grid exports

In the above example you are actually paid for 2kWh of grid exports.  That’s the beauty of net metering with a single-phase inverter on a three-phase property!

This is shown diagrammatically so you can see exactly how net metering works with a single-phase inverter on a three-phase property.

How can you tell if your home is three-phase?

The easiest way to tell whether your home is three-phase is to go to the switchboard and to count the circuit breakers.  A circuit breaker is an electrical safety device designed to protect an electrical circuit from damage caused by an overcurrent or short circuit.

There will be a circuit break labelled as the “Main Switch.”  Looking at this you can tell how many phases of power you have to your property based on the width.  A single-phase switch will be the width of one ‘pole’, and a three-phase switch is the width of three ‘poles’.

Installing a single-phase inverter on a three-phase property is a good solution when you are installing a solar panel system up to 10kW.  It’s cost effective, you get the full benefit of your solar across all three-phases which you’ll see as credits on your electricity bill.

If, however you are thinking of installing a bigger solar power system because your power needs are increasing (i.e. EV charging, large air conditioning system, pool pump etc.), installing a three-phase solar inverter may be worthwhile.

Three Phase Power

Single phase

Get in touch 

Keen to get some price comparisons? Contact us for a quote and further information about the pros and cons of installing single-phase or three-phase inverters on your three-phase property.  We’re one of Australia’s largest Clean Energy Council Accredited Solar Retailers and have the expertise to design a solar system that meets your home’s energy needs today, and into the future.