Bi-directional charging

Elmst-e

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I have been reading of bi-directional charging units for a while now, but it seems always “just around the corner”. I don’t read much on actual usage by average ev owners. I am aware of the f-150 lightning capabilities but it seems very expensive to actually have a system installed at a residence. I can see complications in integrating it with a residence and isolating it from the grid for saftey reasons. I’m wondering if anyone has installed a system and what issues have to be addressed in doing so?
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As for isolating from the grid, that's a device called a transfer switch. The switch connects either one power source (battery) or the other (grid) to your house, and never both.

A large battery is the most expensive part of a backup power system, so it's a great feature if you already wanted backup power.
 
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cryptk

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All of the problems with grid isolation and such are well understood and have been solved for a long time. You have the same problems when setting up a house to run off a generator, which has been a thing for decades. The only thing new here is that it's a battery instead of a generator, but the house side of the equation is a solved problem.
 

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I’ve been wanting a back up system for my house for a few years. Almost went the whole house automatic generator route with natural gas, but they are expensive and for reasons hopefully obvious to most here I would rather a battery. Almost got a home battery to go with my solar system, but I have a hard time spending that kind of money for a battery a fraction of the size of my MME battery that I’ll almost never use (NY has net metering for solar, so no benefit other than power back up). I knew the MME didn’t have this when I bought it, but I might hold another 4-5 years in hopes that my next car does. Fingers crossed for no major power outages in the meantime!!
 


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I have been reading of bi-directional charging units for a while now, but it seems always “just around the corner”. I don’t read much on actual usage by average ev owners. I am aware of the f-150 lightning capabilities but it seems very expensive to actually have a system installed at a residence. I can see complications in integrating it with a residence and isolating it from the grid for saftey reasons. I’m wondering if anyone has installed a system and what issues have to be addressed in doing so?
Sure. Lots of F150 Lightning owners have bidirectional systems operating, some using the expensive Ford Home Integration System, done using simple generator inputs, some even have them integrated into their solar systems. You can read about these in Lightning Owners Forums like these:

https://www.lightningowners.com/threads/my-third-party-home-integration-system-install.2808/

https://www.lightningowners.com/threads/home-integration-system-with-solar-install.1380/
 

MachEMaster

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I’ve been wanting a back up system for my house for a few years. Almost went the whole house automatic generator route with natural gas, but they are expensive and for reasons hopefully obvious to most here I would rather a battery. Almost got a home battery to go with my solar system, but I have a hard time spending that kind of money for a battery a fraction of the size of my MME battery that I’ll almost never use (NY has net metering for solar, so no benefit other than power back up). I knew the MME didn’t have this when I bought it, but I might hold another 4-5 years in hopes that my next car does. Fingers crossed for no major power outages in the meantime!!
It's funny reading your post. I started thinking about a generator for home backup. The quote I got was insane. My gas meter is on opposite sides of my electrical meter, and they were talking about yards of wire and pipe.

I sat back and said why don't I go clean energy and backup battery!? Duh.
I ended up getting a 10.27 kWh PV system, but the 3 power walls required to run my house during an outage just did not make financial sense. We don't have time of use utility rates here. Now that I have a 70 kWH battery parked in my driveway, my problem should be almost solved, with the help of a transfer switch. Maybe my '26 car will do it. Maybe a Cybertruck. Haha.
 

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I don’t understand why these huge batteries in these cars can’t be made to support bidirectional energy transfer. Other than forcing you into a Lightning purchase.
 

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I'm surprised someone hasn't tested out a lighting's inverter tapping the AC's power yet. You can get a soft PPOB switch in sync with a bit flip, just have to put it on the HS1 bus.
 

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I don’t understand why these huge batteries in these cars can’t be made to support bidirectional energy transfer. Other than forcing you into a Lightning purchase.
They could be. But Ford would have to decide to spend money on that project.
 

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They could be. But Ford would have to decide to spend money on that project.
Look, there's no money to be spent. The DCFC connections are a free easy means of tapping the battery. There's no R&D required, just the willingness to allow the battery to be used for such.

Only features that allow for dumb cables to be used need more advanced features on the vehicle. Eventually smart output features will be available as easier means of using the motor inverters to feed power out via the charging port come into play. Parts of the traction inverters would be required to disconnect from the motor's windings and divert that power to the charge port. A more viable option IMO is to have a second 'charge port' that's specifically for V2x operations. That's what makes the most sense to me as it can allow direct / shorter / less complicated runs while using smaller conductors. While adding additional failure points due to increased complexity, it keeps the traditional charging parts unmodified leaving only the V2x capabilities as standalone parts.

Incorporating the parts into an inverter would make the most sense, particularly for adding a standard 20a 120v outlet in a vehicle (or whatever other regional power means are required). Even better if it could be configured to output 20a in either 120 or 240v without additional hardware (like a forscan setting)
 

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I have been reading of bi-directional charging units for a while now, but it seems always “just around the corner”. I don’t read much on actual usage by average ev owners. I am aware of the f-150 lightning capabilities but it seems very expensive to actually have a system installed at a residence. I can see complications in integrating it with a residence and isolating it from the grid for saftey reasons. I’m wondering if anyone has installed a system and what issues have to be addressed in doing so?

1. charge port does not enable bi-directional current on either the AC circuit, or HV DC as far as I know.

2. the on-board vehicle charger is NOT designed to be an inverter/charger. It is not 'grid-forming', and it's unlikely you could run any AC equipment directly because it is not intended to export stable frequency and voltage, nor sync to the Grid.

...that being said...

it is possible to export 12v DC from connection points, and run a little inverter for direct loads as long as you are isolated from the Grid, or charge batteries with a battery charger, etc. I wrote up a couple examples in this thread: https://www.macheforum.com/site/thr...120vac-power-from-lvb-connection-points.7317/
 

axelheimer24

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It's funny reading your post. I started thinking about a generator for home backup. The quote I got was insane. My gas meter is on opposite sides of my electrical meter, and they were talking about yards of wire and pipe.

I sat back and said why don't I go clean energy and backup battery!? Duh.
I ended up getting a 10.27 kWh PV system, but the 3 power walls required to run my house during an outage just did not make financial sense. We don't have time of use utility rates here. Now that I have a 70 kWH battery parked in my driveway, my problem should be almost solved, with the help of a transfer switch. Maybe my '26 car will do it. Maybe a Cybertruck. Haha.
Ha! Too funny. Exact same thing happened to me. A power outage got me thinking about back up power and as I did more and more research, that rabbit hole somehow ended up with 10 kWh PV system and an EV, but no back up home power LOL
 

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Ha! Too funny. Exact same thing happened to me. A power outage got me thinking about back up power and as I did more and more research, that rabbit hole somehow ended up with 10 kWh PV system and an EV, but no back up home power LOL

you are VERY close to having emergency backup.....

Grid-tied PV won't help you in Grid outage unless you have a hybrid inverter and built in transfer switch and batteries. But, with your EV you have all the battery you need!

As long as you are willing and able to follow simple procedures to isolate your house from the grid before using your EV as an Emergency Generator; you do not NEED an automatic transfer switch. All you really need is a little (1500watt) pure-sine Inverter for $300 or less, which you can energize via Jumper cables to your 12v connection points.

Then you can run extension cords to direct loads, OR you can fabricate male-male plug adaptors and 'backfeed' the nearest regular 15 amp outlet AFTER isolating from the grid and turning OFF your Solar circuit. If you backfeed one outlet on each 'leg' of your service panel, you effectively have 'whole house' backup.... but you MUST turn off main breaker, all 240 load breakers, Solar backfeed breaker, and all non-critical 120v loads to keep the maximum load well below 1500 watts if you are extracting energy from your MME.

*** Manual isolation, and use of male-male adapters with any Emergency Generator is NOT fool proof, and presents shock hazard if procedure is not followed. ***
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