Vehicle to grid charging

[mrgeorgemartin]

I am new to the I3 forum. I am considering buying the new I3 however does anyone know if if it is possible for the I3 to be compatible with vehicle to grid charging like the new Nissan Leaf? George Martin

 

[alohart]

I am considering buying the new I3 however does anyone know if if it is possible for the I3 to be compatible with vehicle to grid charging like the new Nissan Leaf?

It's theoretically possible. However, BMW doesn't advertise this possibility, and I've never read about it being done, so don't count on it.

 

[vreihen]

I'm curious why anyone would want to put extra charge/discharge cycles on their EV battery pack to sell electrons back to the power company?????

 

[Fisher99]

I'm curious why anyone would want to put extra charge/discharge cycles on their EV battery pack to sell electrons back to the power company?????

And then have your EV not fully charged when you need to use it because it gave some of its charge back to the grid. Doesn't make sense to me either.

What I do find intriguing, however, is the potential to power some basics in my house (a few lights, the fan in the propane fireplace, etc) in the event of a power grid failure.

 

[jadnashuanh]

I think that I read somewhere that Japan was going to require this capability...not positive on if or when that may be true. Makes sense that the Leaf would include it.

This capability is being worked on in the USA. There are expected to be settings where you can decide to participate or not, and set in desired departure times so that the system can ensure you aren't left with a low battery when you need to go somewhere, assuming you don't have a spur of the moment departure. There has been a draft protocol running around for comment for over a year.

Doing that should allow the whole grid to become more efficient, and likely help to keep prices down since they could tap into that stored energy to meet some peak demands, and, charging at night helps to keep the load level, also improving efficiency when using fossil fuels by not having to start/stop them which is less efficient.

 

[robthebold]

I'm curious why anyone would want to put extra charge/discharge cycles on their EV battery pack to sell electrons back to the power company?????

Buy low, sell high, I suppose? Although I doubt there's a power utility in the world that actually has a spread that would be worth it . . .

 

[jadnashuanh]

Firing up a generator to fill a peak load is expensive. While a NG fired one can be brought on line fairly quickly, a coal-fired one takes a lot longer to come up to temperature. Even needing a generator to fill in on those peak loads is expensive. So, from an infrastructure viewpoint, being able to tap a stored energy source nearly instantly can help with those peaks and negate the need to have an expensive plant sitting on standby or to build it in the first place. Utilities have agreements to buy power from others, but that doesn't always work, plus, at least in the US, people object to building new power lines required to bring in that extra power, and upgrading them to handle more power. The further you have to move power, and the more of it, upgrading the grid becomes more important. Something that people just don't want. For example, Ontario, Canada has a surplus of hydro power, but they power company has been trying for nearly a decade to get permission to build a transmission line to bring it to New England...hasn't happened, probably won't, and they don't want new power plants built, either...something has to give eventually. Car to grid has some advantages over building new. Those costs not experienced by new transmission lines or power plants should help in keeping costs under control. Only, though, if cars and the logic starts to show up.

FWIW, I asked this at a BMW dealership...I was told that BMW is looking into incorporating it in future MY vehicles...how soon, can't tell. May change now with a new top guy in charge.

 

[MagicCarpet]

V2G might be possible with the Japan model i3 which has a Chademo rapid charge connector as does the Leaf, a bidirectional DC flow is part of the spec.
This would only be useful if a cheap enough inverter is available on the market and I think only useful in times of power mains outages, rather than a grid tied system.
The i3 has a hefty 14.5V stud under the rear floor that is topped up by the HV battery via a 200A inverter. It feeds the 12V battery and I observe with a digital display when the car tops up it goes from 11.8V to 14.5v in less than a second
Wonder if that terminal could be connected to a socket to run an inverter for standby power?
Even the Tesla Powerwall is not very useful as far as I know it wont work as a standalone AC supply.
I like having a standby genset at home and currently this is the most economical way to do it.
Agree that wearing out my EV battery to save a few $ on mains power is not a likely scenario
Ralph

 

[vreihen]

Even the Tesla Powerwall is not very useful as far as I know it wont work as a standalone AC supply.
I like having a standby genset at home and currently this is the most economical way to do it.
Agree that wearing out my EV battery to save a few $ on mains power is not a likely scenario

When the i3 was initially launched, BMW touted their plan to recycle the aged battery packs into home power storage units like Tesla's power wall. That seems to make way more sense for a V2G scenario, since you're not putting those charge/discharge cycles onto your car's batteries......

 

[Obioban]

I could see this being a desirable feature for people that are leasing, that'll never cycle out their batteries in their 3 year use of the car.

... I've never leased a car, so do not want.

 

[jadnashuanh]

FWIW, some of the batteries in the original Prius cars are still viable and that chemistry is more prone to failures than the more modern stuff...IOW, the batteries should have a very long useful life, although, maybe not in a vehicle. My typical driving need is less than 30-miles, and with the weather we are having now, it is regularly reporting more than 80 being over 5-years old and plugged in each time I get home.

 

[i3Houston]

Dont think the intent is to buy low sell high. I think technology would involve into something like Nest Thermostat, here in Houston, Nest can integrate with Center Point Energy and then raise the temperature during the Peak demand. Similarly, when Japan's energy grid can see cars hooked up in V2G mode, Energy companies can switch those home's power source from Grid to Vehicle, reducing the load on the Grid.

Assuming a single family home in Texas at Peak summer consumes 10-15KW per day, the usage during the peak hours would be ~5KW, which is a small percentage of ~18KW i3 battery.

 

[jadnashuanh]

As I understand it, the main goal of V2G is to help balance the load on the grid so that it doesn't need expensive power plants to come on-line to fulfill that momentary need. As a result, the utility doesn't need to invest maybe hundreds of millions of dollars for a plant that may only need to be used infrequently. This keeps the costs down for everyone. To be fair to an owner, the power provided by their battery should be replenished the same rate both ways at a minimum, and ideally, receive a credit for being a supplier during the peak needs.

In areas where there's a lot of solar or wind, if a vehicle could be charged when that power is in excess, that would help, too while letting the rest of the grid suppliers from fossil fuels maintain their consistent output...think of the batteries as a buffer. Balancing the needs of the grid versus the needs of the user so that the vehicle had enough charge to do what is needed when needed is part of the complication.

Just was reading about a new technique of building LiOn batteries on silicon wafers...faster recharge rates, less degradation, at least double the energy storage per pound, and less expensive. First applications may show up next year, but they've been demonstrated in utility storage situations already. Current design maxes out at around 100Kw. Battery degradation will become a non-factor in the future...building the infrastructure to take advantage of it should be starting now.

 

[Slymp]

Hi,
Sorry, a bit late on this. I've been thinking about something like a Tesla powerwall - lifepo4 etc. No solar, yet. Charging at cheap rate (5p/kwh here in UK), and using the battery during the day. My domestic consumption is about 7kwh /day. I've no intention to sell back to the grid.

So, I could spend £4k+ buying batteries, but I have a 33kwh i3 battery sat in my drive. It's got plenty of juice for me.

All I (we?) want is a cable with a 1kw inverter!

Steve

 

[raylec]

There are some public charge outlets that are free to use,so charging your car here and going home to run your house with free power is an interesting thought.!