Bidirectional Charging / V2H / Solar when grid is down.

[millim]

Just finalized my preorder last night for a Platinum and am excited for the future. We have solar at home, and where we live we have occasional power outages that are generally associated w/ SoCal Edison powering off the lines during high winds/high fire danger days. Beyond that I appreciate that our grid is old and over-stressed, and can imagine outages may become more regular.

One of the benefits of a Powerwall is that even when the grid is down, if there is excess electricity generated by your solar you can charge the Powerwall (duh). If the San Andreas fault goes big during my lifetime that could end up being clutch.

I suspect Ford's bidirectional charging won't be capable of specifically powering a house and charging your Lightning at the same time, but I am wondering about a specific use case.

Assuming you've installed the required hardware for bidirectional charging to work (including the inverter at home), can you use solar to charge the Lightning while the grid is down (assuming you aren't trying to power your house at the same time)? Then, after charging, could you swap directions and return to powering the house?

In other words, if it's a prolonged outage, can it accomplish both directions while the grid is down, even if it isn't at the same time?

TIA

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[GoodSam]

Says here that Tesla Powerwalls can operate, store solar, while off-grid.
https://www.sesre.com/tesla-powerwall-off-grid-compatible/
I would think the same would apply for a EV battery backup. Hopefully someone else will have a definitive answer.

 

[millim]

Says here that Tesla Powerwalls can operate, store solar, while off-grid.
https://www.sesre.com/tesla-powerwall-off-grid-compatible/
I would think the same would apply for a EV battery backup. Hopefully someone else will have a definitive answer.

Agreed. I've been assuming they are largely similar, especially given how the media portrays them, but it's a pretty significant difference if they can't/won't. Hoping for confirmation from someone much smarter than me.

 

[williams]

I have solar with Tesla power walls, the real question is can the system tell the truck the power is off and pull from the truck instead of the power walls to let the house be longer stand alone. Id rather pull from the truck, you know if i ever get it instead of the power walls incase its an extended black out, and i can charge at work. Let the powerwalls and solar maintain the house.

 

[adoublee]

Ford representative on InsideEVs show communicated it will be possible for a knowledgeable installer (if not only Sunrun if software key limited) to arrange for excess solar to charge the Lightning when isolated from the grid.

It is not obvious to me yet if this would be only solar connected into the DC-Solar port of the HIS bi-directional inverter, only excess solar coupled through the AC port of the HIS bidirectional inverter, or both. I gotta think the solar charging would take place through the DC line to the truck versus the home AC system and back through the onboard charger, but that does suggest the truck could charge at 9.6kW through the DC pins of the CCS connector...

 

[millim]

Ford representative on InsideEVs show communicated it will be possible for a knowledgeable installer (if not only Sunrun if software key limited) to arrange for excess solar to charge the Lightning when isolated from the grid.

It is not obvious to me yet if this would be only solar connected into the DC-Solar port of the HIS bi-directional inverter, only excess solar coupled through the AC port of the HIS bidirectional inverter, or both. I gotta think the solar charging would take place through the DC line to the truck versus the home AC system and back through the onboard charger, but that does suggest the truck could charge at 9.6kW through the DC pins of the CCS connector...

Thx for this. I can't imagine why anyone who has solar wouldn't want this option. I suspect they'd have some very pissed off customers if the default is not to have this enabled (if it is indeed an option).

 

[Ken]

This topic came up in another thread and I think the answer was that the current wiring setup of the charger would not support simultaneous charging of the truck via solar and powering the house. i agree it should be a capability, but there's something different about the powerwall setup that allows it from the powerwall but not the Lightning. It would be nice to get a definitive answer about this one either from Ford or Sunrun.

 

[millim]

This topic came up in another thread and I think the answer was that the current wiring setup of the charger would not support simultaneous charging of the truck via solar and powering the house. i agree it should be a capability, but there's something different about the powerwall setup that allows it from the powerwall but not the Lightning. It would be nice to get a definitive answer about this one either from Ford or Sunrun.

Thanks for sharing. My main point is that I hope it can, at a minimum, be able to charge the car w/ solar even if the grid is down, even if it can't power the house at the same time as it charges the car.

 

[Ken]

My current solar system has a lockout switch and an internal 120v outlet, that could trickle charge the truck in the event of a power outage, but it wouldn't be very fast. It's intended as emergency power for a freezer or some other device you want to power, but it would only work during enough daylight to generate the power.

 

[Mr. Flibble]

Thanks for sharing. My main point is that I hope it can, at a minimum, be able to charge the car w/ solar even if the grid is down, even if it can't power the house at the same time as it charges the car.

Realistically speaking, the truck won't care where the power is coming from, it will just charge if there is power. If you have the main grid down, but solar producing power, by default you should be disconnected from the grid because you don't want to be back feeding power into the grid when it is down, lest you kill a lineman. Same reason you disconnect when going on generator.

So, you basically do the same thing as a generator, but instead of the generator, you just have solar. (Its probably a little more involved, but the concept is the same.)

 

[bryan995]

I highly doubt this will be possible, but we shall. I give it a <1% chance

In a grid down situation, you'd have to be able to send all solar power to the truck, the truck then converts it and sends the necessary power onto the house while charging its own batteries with any excess. THEN as the truck's batteries fill, it would have to be able to shut down the solar and continue running the home until its batteries drain enough that solar could come back online and start re-charging the truck.

Yeah right...

To efficiently peak shave (with grid), the system needs to know when the cheapest and most expensive times of the day are. It then prioritizes charging batteries during cheaper times and discharging batteries during PEAK rates. Solar is then diverted back into the grid to be sold for higher credits. Very hard to do this with a mobile home-battery-pack. Powerwalls also fully charge and fully discharge EVERY day. I HIGHLY doubt Ford would want to strain the vehicles batteries in such a way, AND retain the warranty...

If you want a true backup system, stick to the solar+powerwall.

 

[Mr. Flibble]

I highly doubt this will be possible, but we shall. I give it a <1% chance
You'd have to be able to send all power to the truck, the truck then converts and send power to the house, and then charges itself with any excess. THEN it would have to be able to shut down the solar when its own battery becomes full and continue running the home.

Yeah right...

If you want a true backup system, stick to the solar+powerwall.

You don't have to send all power to the truck. You send all power to the house. The truck is part of the house/charging. As long as you are producing enough excess energy to power your house, you can charge the truck too.

The Powerwall has a 13.5kWh battery - the F150 has 98kWh or 131kWh.

This video isn't perfect, has a few inaccuracies, but is in line with the general ideas:

 

[adoublee]

You don't have to send all power to the truck. You send all power to the house. The truck is part of the house/charging. As long as you are producing enough excess energy to power your house, you can charge the truck too.

The Powerwall has a 13.5kWh battery - the F150 has 98kWh or 131kWh.

This video isn't perfect, has a few inaccuracies, but is in line with the general ideas:

Standard house charging doesn't adjust rate based on how much extra solar their is, and that will fluctuate in real time. Difference would have to be made up by the battery through the DC to DC converter of the HIS and DC to AC converter of the HIS, effectively making them toasters. Maybe controls addresses this if system knows it off grid but don't expect that is the case.

What you are describing is more possible if AC charging is halted and DC port is allowed to send or draw to maintain battery at top voltage while powering home. Voltage control instead of current control.

 

[millim]

So I went to the Sunrun site and see the following, so unless I'm reading it wrong we *should* be good with this approach even if the grid is down for an extended period of time.

https://www.sunrun.com/ev-charging/ford-f150-lightning

Power through outages
Use your F-150 Lightning™ battery to fully power your home for up to 3 days, or power just the essentials for up to 10 days*. With a solar energy system, your panels will gather energy whenever the sun is shining to help keep your home powered and truck charged no matter how long the grid outage lasts.

*When home is properly equipped and home transfer switch disconnects home from the grid. Based on 30kWh use per day using the F-150 Lightning with the extended range battery. Your results may vary based on energy usage. Rationing power assumes limiting the number of devices and turning the truck off when not needed.

 

[adoublee]

So I went to the Sunrun site and see the following, so unless I'm reading it wrong we *should* be good with this approach even if the grid is down for an extended period of time.

https://www.sunrun.com/ev-charging/ford-f150-lightning

Power through outages
Use your F-150 Lightning™ battery to fully power your home for up to 3 days, or power just the essentials for up to 10 days*. With a solar energy system, your panels will gather energy whenever the sun is shining to help keep your home powered and truck charged no matter how long the grid outage lasts.

*When home is properly equipped and home transfer switch disconnects home from the grid. Based on 30kWh use per day using the F-150 Lightning with the extended range battery. Your results may vary based on energy usage. Rationing power assumes limiting the number of devices and turning the truck off when not needed.

Expect charge rate of no more than 9.6kW to the truck when isolated from the grid if that matters to you.

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