EG4 Gridboss with Bi-directional EV Charger (smart port)

[BackyardBandit]

Tesla now has the Powershare feature for the Cybertruck allowing bi-directional flow to act as a home backup. The system uses a Gateway which acts as the MID and is basically a 200A transfer switch. When grid fails, the truck becomes the power source for connected loads. (48A 240V AC). When grid signal is good, EV can charge.

Tesla only has one wiring option for homes with 3rd party backup (battery systems, generators, or both). They essentially want everything to run as two independent systems, each feeding separate load panels. (see snip). This is obviously not a great option for anyone wanting everything to operate as one system.

Trying to figure out how to implement this with the Gridboss. Wondering if the whole thing could just connect to a smart port, but not sure if the smart ports can be programmed to be bi-directional and switch flow direction based on whether grid is up or down. IE: Grid up, smart port acts as a load to charge the EV... Grid down, smart port allows EV to act as an AC coupled source. Then there is the issue of how the Tesla gateway distinguishes between whether grid is up or down

 

[CaySol]

Maybe with a firmware update because the smart ports are bidirectional already. But I think currently you have to choose between ac coupled or output in the settings. Not dynamic.

 

[Mark D]

I want to do that same thing basically but with off grid solar. Haven't had much success finding any options though. Hopefully your research will be more fruitful. The difficulty lies in manufacturers providing the capability in the first place. It's easy if you don't mind using two ports and manually managing the power flow but that's hacky and lame af

 

[Usernameinuse]

Look over here for a bit more:

Post in thread 'Flexboss21 and Gridboss'

Mar 3, 2025

At this time, we do not have any firmware updates for the Flexboss. However, as soon a new firmware update becomes available, we will be sure to share it with everyone.

Thanks for the update. Do you have any comment on the ability to use AC coupling when grid is down? Is that a potential functionality in the future?

• Usernameinuse

• 

Short answer: kinda.
The smart port relay when the grid is up pushes power to my grid-tie inverters waking them up, then receiving power flowing back.
When the grid goes down though, the relay is just opened and dead in the water.
Still trying to get an answer from EG4 why we can't keep that smart relay closed when grid is down. After all, the device is called a MID, and has microgrid right there in the name.
Why can't we still have ac-coupling when grid is down.