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Discussion Starter #1
I've read estimates that more than 1 million EVs will be on U.S. roads by 2020 (I think this is an underestimate), and after that point, the EVs might start impacting the grid. Even if that is not the case, I have read that the leveling that EVs with V2G capability could save utility companies more than $4,000 per year per vehicle.

I realize that no standards have yet been established, but I also haven't seen much forward movement by GM on the V2G front. The Volt and Bolt both seem like excellent options to test out the technology.

I realize that many hurdles stand in the way (beyond just the standardized technology), but in my opinion, the most important hasn't really been talked about: EVs are (by their nature) mobile. So we have to establish opportunities for EVs to be grid-tied in multiple locations. It's an issue of both time and space.
 

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Aside from the energy losses in electricity flowing from the car to the electric distribution network and back, I have a couple of problems with this.

First is that my driving habits cannot be predicted. Sure most often the car sits in a lot 9 hours, 5 days a week rarely moving, but on the off day that I need it....... and for that matter, the power company can't rely on me to be there when they need me most.

Second is placing trust in the power company. I know many folks leave their car plugged in all night. I only do this in winter. Spring through fall I unplug when it's finished, reducing my exposure to spikes and surges. Additionally, when a thunderstorm comes through in the middle of the night I don't have to jump out of bed to unplug, in the case where a surge would be mother nature's fault.

If power companies need storage, I think dedicated facilities should be in their toolbox.
 

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The J1772 format does not support V2G.
The car has to have wires that handle the ~400 VDC at the port.
I have read that Chademo was designed with V2G as a future possibility.
SAE combo might be able to be tweaked to play.

But still, the DC coming out of the car has to be converted to synchronous 120 VAC to be fed to the grid.
That means a big box mounted somewhere near the vehicle, extra cycles on the battery, who pays for all this, being surprised your range is not what you expected, etc...
Yeah, for now it's 'Pie in the Sky'.
 

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Being able to use a vehicle like a Volt as an emergency generator would be an awesome feature. Where I live, I have a gas generator in case of power loss so I have access to my well water. I could live with the extra wear and tear on my battery for a couple of days.
 

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Some valid concerns raised here about V2G. One option that was demonstrated in Japan was not V2G but for applications when electricity was needed and the grid was down. IIRC, the LEAF battery was used to power lights. Given the fragile nature of the LEAF battery, I am not sure I would use my LEAF for V2G.
 

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Being able to use a vehicle like a Volt as an emergency generator would be an awesome feature. Where I live, I have a gas generator in case of power loss so I have access to my well water. I could live with the extra wear and tear on my battery for a couple of days.
V2G is for feeding back into the utility grid, not backup power for outages. Using your volt for backup power is a whole different issue. It's solely for your benefit, not helping out the utility company and their stockholders. I expect V2G would work like a grid-tie solar system, if the grid is down the solar system shuts off so it doesn't back feed into the grid and possibly endanger line workers, etc.
 

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Discussion Starter #8
The J1772 format does not support V2G.
The car has to have wires that handle the ~400 VDC at the port.
I have read that Chademo was designed with V2G as a future possibility.
SAE combo might be able to be tweaked to play.
It seems like this technology has already been tested on Teslas, Priuses, and Escape Hybrids.

Tesla
Prius and Escape

But still, the DC coming out of the car has to be converted to synchronous 120 VAC to be fed to the grid.
That means a big box mounted somewhere near the vehicle, extra cycles on the battery, who pays for all this, being surprised your range is not what you expected, etc...
Yeah, for now it's 'Pie in the Sky'.
I think the idea is that EVSEs and public charging stations would have built-in, two-way functionality.

I would be fine with it if I, as the owner, controlled the characteristics of the V2G connection. In most cases, it looks like they were testing with only about 1 kWh of usage per vehicle. In a Volt, that would cost you about four miles of range, but I don't see how it couldn't work the same way as the "Departure Time" charging feature. That would ensure that your battery was fully charged by the time you would leave (i.e., your battery is off limits for V2G purposes).

For cost, I would think that the utility companies should pay (both for the equipment and the vehicle/energy usage). For the program to work, the owner could opt in and be compensated for usage.

Some valid concerns raised here about V2G.
I agree, but I think the biggest concern in terms of viability is having the option to plug in wherever the car is parked for an appreciable period of time.
 

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It seems like this technology has already been tested on Teslas, Priuses, and Escape Hybrids.
....
I think the idea is that EVSEs and public charging stations would have built-in, two-way functionality.

I would be fine with it if I, as the owner, controlled the characteristics of the V2G connection. In most cases, it looks like they were testing with only about 1 kWh of usage per vehicle. In a Volt, that would cost you about four miles of range, but I don't see how it couldn't work the same way as the "Departure Time" charging feature. That would ensure that your battery was fully charged by the time you would leave (i.e., your battery is off limits for V2G purposes).

For cost, I would think that the utility companies should pay (both for the equipment and the vehicle/energy usage). For the program to work, the owner could opt in and be compensated for usage.

I agree, but I think the biggest concern in terms of viability is having the option to plug in wherever the car is parked for an appreciable period of time.
Those examples in the links where highly modified cars. The Prius had added batteries, which makes sense. The stock hybrid Prius has a tiny battery, the Plug-in-Prius has a slightly bigger tiny battery.
Those are just strange experiments.

Current EV's can't do any V2G. Supposedly Chademo was setup to allow for it in the future. I could see a Leaf owner out in the boonies buying a 400VDC to 120VAC inverter for home use, and then only during grid outages.
(Those Leaf batteries have a hard enough life as it is...)

And the whole idea of PUBLIC charging is to 'Chit and Git'. You need electrons, you get electrons, you leave, immediately (if you are a nice EV driver).

Vehicles are one thing and the Grid needing storage is another.
Why combine them. Most people need their EV's ready to roll.

There is a grid storage system that uses thousands of Volt battery cells in small buildings. It's in use now.
It was talked about on this forum. Don't have time to find the link.

It's true, with wind and solar being added to the grid daily, energy storage solutions will be needed.
 

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Discussion Starter #10
I can't argue with your logic. The main advantage I see with V2G is killing two birds with one stone, especially if the technology can be used to create a local micro grid. Otherwise (and I think this is going to happen regardless), we can achieve the same results by the installation of home battery backups (e.g., Tesla's PowerWall). Frankly, though, I think that utility companies will be loath to encourage home battery backup systems because it will put homeowners one step away from pulling the utility plug completely.
 

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I can't argue with your logic. The main advantage I see with V2G is killing two birds with one stone, especially if the technology can be used to create a local micro grid. Otherwise (and I think this is going to happen regardless), we can achieve the same results by the installation of home battery backups (e.g., Tesla's PowerWall). Frankly, though, I think that utility companies will be loath to encourage home battery backup systems because it will put homeowners one step away from pulling the utility plug completely.
I started seeing advertisements on TV for a solar/battery storage combo here in the SF Bay Area, and it's not Tesla. The company is Petersen Dean [http://petersendean.com/residential-energy-storage/]. I didn't see what type of battery was in the energy storage system.
 

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Discussion Starter #12
Battery-tie systems really aren't that complicated; the big expense is the inverter. I think this is a perfect application for sodium ion batteries that are currently being developed: Cheap and heavy... but cheap.
 

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DCFC (SAE Combo) can support V2G, as the charger is in the EVSE unit, not the car. The DCFC inlet gives you direct access to the HV battery. Of course a custom EVSE is necessary to allow the two way flow, but a 400VDC to 120VAC inverter is very feasible for home backup. I intend to do exactly that if/when I get a DCFC EV.
 

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I'm really not a fan of V2G. If I were doing it to compliment my own solar power system or something, I could see that. But I don't want to have extra wear and tear on my car's battery, cooling, and electrical system just to help out the electric company. Not only that, but I always unplug during thunderstorms. And I don't want to risk going out to my car and having anything less than a full battery when I leave my house.
 

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DCFC (SAE Combo) can support V2G
Certainly it will depend on the vehicle, and sure, there will be mechanisms to prevent HV being present on the open connector. I don't have access to the SAE specs, but have had discussion with an installer of DCFC stations in Austin, and that is their expectation, long term.
 

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Guys,
As an owner of a EV with 50 kW DCFC capability, I expect to plug in, get a big load of electrons, and leave 10-15 minutes later.
Why/when would I ever want to plug into a DCFC and have my battery drained?
 
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