Off Grid System backed up by EV rather than generator

Hi. We are building a new house in Gippsland and hoping to be off grid and use our BYD Atto as a back up, rather than a generator. The companies we have quoting are struggling to work out the best way to set this up. I have read the threads on this forum, which have all been very helpful, but was wondering whether there was a definitive way to set this up that I could share with the local companies?

I understand the atto has a V2L capability of 3.4kw, or 15 amps. Theoretically you could possibly have a generator transfer switch and generator inlet to your switch board installed as if you were connecting a generator by extension lead. Instead, plug the ATO V2L connection to this. This could power 3.4kw of household load.

Thanks. The people doing the quotes are working on the idea of connecting the BYD to the inverter so that the car battery can charge the house battery if needed. I guess connecting it directly to the switchboard would make it a more direct back up so that it’s running the necessities?

This is not correct. The maximum continuous output is 10 Amps or 2.4kW. It can peak at 15A, but it very unstable and should not be pushed at this level. Here is a link to my test results… BYD Atto 3 V2L load testing - Vehicle-to-load power output

As an off-grid installer with a BYD Atto3 myself, I would not recommend only using your BYD for backup in Gippsland based on the climate. The problem is the very limited 10A output from the BYD is probabaly not enough to charge your off-grid system and power your loads (unless you have a very small system and you have very low loads).

What is your daily estimated daily energy consumption for your new home? I’m assuming you have done a detailed load table with your installer.

Thanks Svarky. Will of course defer to your knowledge. Yes, BYD whilst would do 15A peak it wont continuously. Should have been clearer.
The thread that you link to is awesome and sats it all really.

Hi Jason,
Thanks for your reply. The form they provided estimated our daily consumption at 22 kWh, though it did seem to assume that you used every appliance at least once every day, which would seem unlikely. We have the option of being on-grid since the nearest connection point is at the start of our drive, about 180m from house. The quotes we have for being completely off grid are very high and probably beyond the scope of our budget.

Hi, I’m assuming that is your average winter consumption, correct? The cost to run underground cables from a new grid connection point my also be very expensive.

Feel free to contact me directly, as I could also offer you a quote. I’m based in Kinglake but have done some work in Gippsland. Look up my company Transfer Solar.