Single phase solar with 3 phase X22

Hi - I am considering buying a 22kW X22 charger. I have a 3 phase grid connection and a 6 kW enphase solar system. The enphase system only seems to be feeding one of the three phases.

Will the X22 be able to provide solar only, solar + 3 phase grid top up and 3 phase grid only charging?

thanks.

Hi there.

The short answer is yes, but there’s a bit of nuance in there which means you may also need a longer answer…!

First it’s worth mentioning that your car may only charge on one phase - many new ones will charge off all three but some don’t. And almost all three-phase ones will still only charge at 11kW rather than the full 22kW, so bear that in mind too.

The X22 will monitor all three phases, and will look at the net export across all three to decide how quickly to charge under “solar-only” mode. So if you export 6kW on one phase and 0kW on the other two, then it will charge at 6kW to balance that out. This is done by supplying 2kW to the car on each phase (phases have to remain balanced to the car). So in a net calculation you will consume your 6kW of solar, but under the hood there will technically be import on some phases and export on others.

If you want to consume from the solar and grid then you can charge at full speed during the day. The maths for your power bill will cause you pay for just the proportion of the energy which came from the grid.

Finally grid only charging can occur whenever there’s no surplus solar beyond your home consumption. If there is a surplus then the only way to “prevent” it from going into the car is to stop charging.

Having said all of this, my gut feel is that the best option for you would actually be an X7 charger because your solar setup is less than 7kW so it will never need the speed that an X22 can deliver. The X7 can monitor all three phases and ensure you match the net import / export, even though it will only charge on one phase. The only reason to get an X22 would be if you think you will occasionally need to charge at higher speeds from the grid (and even then you may well be limited to 11kW by your vehicle).

If you choose this option then mention to our sales team that you have a three-phase home so that they can ensure we send three clamps to measure all three phases (by default the X7 only comes with one to measure one phase).

Kind regards,

Tom

Great - thanks Tom for the comprehensive explanation. Good to know that it will work.

The car is max 11kW but I expect I will need to charge quickly from time to time so will go with the X22 I think.

  • Peter