[ChristophW]

Does anyone know whether ID.3 and ID.4 are ready for vehicle to grid, i.e. letting electricity flow back out from the car? And has VW said whether they want to support it?

I know that Tesla, for example, takes a negative stance on vehicle to grid for now, and per Sandy Munro the Model Y onboard charging board cannot support reverse electricity flow due to four large diodes in the path instead of (presumably more expensive) transistors.

 

[emtonsti]

That would be very cool! I think Nissan? or someone else introduced V2G in Japan or Korea? But, I guess you need another expensive box between the car and the home, so not sure what the initial investment would be (says the guy who spent ridiculous money covering the roof with LG solar panels before the price drops of recent years).

V2G can be particularly efficient, because the exchange is done at the vehicle's high voltage, the traction battery voltage.

 

[ChristophW]

Yes, Nissan does vehicle to grid for fleets. In the LA area the US Army has a bunch of Leafs and the necessary infrastructure.

A bunch of companies make bidirectional chargers, including ABB in Europe and Nuvve here in my town. They are expensive, I saw a price of $4000 at the turn of the year. However, if I can arbitrate between my 4pm-10pm high peak rate of $0.53/kWh and the midnight to 6am night rate of $0.09/kWh, that will pay for itself eventually. And it would help stabilize the grid while I make money.

 

[corfam]

During previous research for EVSE install, I noticed that PG&E (in California) specifically prohibits back-feed to the house (Link, reference CEC §625.25). I'm not sure how many other electric providers would have such a prohibition, but it's worth checking with your provider.

 

[ChristophW]

That CEC section is really sad and behind the times! I suppose I’d have to connect a bidirectional charger to my solar panel inverter and home battery, and therefore technically feed/help the PV system, not the house. Unless the code changes soon. Jeez!

 

[emtonsti]

That CEC section is really sad and behind the times! I suppose I’d have to connect a bidirectional charger to my solar panel inverter and home battery, and therefore technically feed/help the PV system, not the house. Unless the code changes soon. Jeez!

That is a really interesting possible approach. How large is the home battery, which company? Which solar inverter are you using?

 

[ixlr08]

If you were to do this, you would be cycling the EV's battery more often, what will that do to battery life?

 

[kimielnielson]

As for me, our future is electric cars and solar panels.

 

[Reeler]

Tesla is against this because they want to sell powerwalls. V2G cycling for blackouts at least would be great. Many parts of the country (and certainly less developed nations) have unreliable power. Just as an emergency backup option would be great.

 

[ChristophW]

@emtonsti My battery is an LG Chem 8.5 kWh unit configured to only cycle 5kWh. Works really well in practice and keeps the house on our own energy from sundown until 10pm or longer. The inverter is a SolarEdge SE3800.
The PV system is disconnected from the grid when the power company is working on it or when we have a blackout. This protects the workers and is likely the reason for the CEC rule on vehicle chargers. If a V2G connection to the inverter is possible it would technically be safe and hopefully legal.

@ixlr08 I am not much worried about increased cycling at the low rates for the house or grid. At 7.6 kW max you are nowhere near stressing the battery hard. And you can set limits to how full or empty you allow the car battery to be. I'd opt for cycling between about 40% and 80%. I mean, it's a car, I want some juice and range at all times.