Use your car as a battery?

[JamesPa]

Octopus have just launched a use your car as a battery tarrif

 

https://octopus.energy/power-pack/

 

At present its more or less only the Leaf which is compatible, and you need a specific wall charger, so its pretty limited, albeit (in my view) the inevitable future.

 

I have a feeling (but someone please correct me if Im wrong) that only CHAdeMO currently supports V2G (hence pretty much leaf only), I think the CCS and Tesla charging protocols are both promising it in 2025, although Elon musk is apparently on record as saying that V2G isn't useful (presumably because he prefers to sell powerwalls).

 

[ToughButterCup]

[AliG]

I just bought a Kia EV9 which has been designed for this feature and will likely be compatible at some point.

 

However, to take advantage of this with Octopus you have to move from Intelligent Octopus. So you would get car charging for free but pay full price for your other electricity.

 

As we can charge the car overnight at 7.5p, the saving from being able to charge it for free is small and much less than the extra cost of all the other electricity being full price.

 

However, we use a lot of electricity overnight. If car charging was your main electricity use you could save by moving to this plan. It is, however limited to 333kWh per month.

 

So the maximum saving if you are on Intelligent Octopus is £25 a month or £300 a year. Chances are that you will save less as you will not use exactly 333kWh every month.

 

Offsetting this the special charger required might cost £2-3000.

 

Basically I'd stick with IO.

 

Further gas and electricity prices continue to fall. We are paying less than 4p for gas on Octopus Tracker now. Electricity prices should fall quite substantially over the next 6 months.

[JohnMo]

Not sure I would sign up unless the car was leased.  Suspect they will be borrowing your battery power to suit the network, not your car battery life. Note the title V2G not V2H - grid not home.

Edited February 19 by JohnMo

[Dillsue]

5 hours ago, JamesPa said:

At present its more or less only the Leaf which is compatible, and you need a specific wall charger, so its pretty limited, albeit (in my view) the inevitable future.

 

 

I'm guessing that Octopus have a cunning plan for this but seems there's no approved Wallboxes on the ENA inverter database. I guess if you were on one of the V2G trials you could use the tariff but seems that everyone else will have to wait for Octopus to show their hand? Anyone know differently?

[Roger440]

3 hours ago, JohnMo said:

Not sure I would sign up unless the car was leased.  Suspect they will be borrowing your battery power to suit the network, not your car battery life. Note the title V2G not V2H - grid not home.

 

Am i missing something obvious. Why would i want to supply the grid from my car. My house , yes, can see that benefit, but the grid?

 

[JohnMo]

11 minutes ago, Roger440 said:

 

Am i missing something obvious. Why would i want to supply the grid from my car. My house , yes, can see that benefit, but the grid?

 

They are giving free charging - you don't stuff like that without payback.

 

Words from the website

We’ll set up your V2G charger to automatically manage your charging and discharging in the greenest way possible, so you can fill up for free.

 

and then export back to power your neighbourhood when the grid needs help

[Andehh]

For what it's worth battery technology is my speciality, and premature degradation doesn't exist on modern battery types. Automotive stuff (other then random hardware failures) is lasting significantly longer then most expected. Fast charging /fast discharging very regularly can have an issue long term but v2g type tech is tickling the battery, which would probably be the difference if it lasting 250k miles vs 300k miles! Ie beyond cars usable life.

[JohnMo]

5 minutes ago, Andehh said:

what it's worth battery technology is my speciality, and premature degradation doesn't exist on modern battery types

Tell that to my phone.

 

Did you see the top gear episode here they tested a used Nissan Leaf, about 5 years old and the range was less than half of what it should be.

Edited February 20 by JohnMo

[Dillsue]

10 hours ago, Roger440 said:

 

Am i missing something obvious. Why would i want to supply the grid from my car. My house , yes, can see that benefit, but the grid?

 

Maybe to stop a coal fired power station from starting up, or remove the threat of blackouts, or keep a gas power station on peaktime standby rather than running, or store some wind generated leccy rather than turn turbines off. Whole host of reasons when you look at the bigger picture, in addition to free charging

[Andehh]

19 minutes ago, JohnMo said:

Tell that to my phone.

 

Did you see the top gear episode here they tested a used Nissan Leaf, about 5 years old and the range was less than half of what it should be.

 

Only talking to automotive batteries, and modern chemistry only. The leaf battery was launched about 15 ish years ago? Mobile phones are also probably killed off with aggressive use and fast charging! They are a totally different chemistry as well.

[JohnMo]

27 minutes ago, Andehh said:

The leaf battery

But that is the only vehicle being offered by Octopus for V2G!

[Originaltwist]

Don't forget though that more vehicles already support V2L ... like a 3kW mains supply behind the front seats .... and you don't need an expensive charger for that.

@Andehh - any suggestions for a suitable second hand EV with the right battery please.

[Square Feet]

40 minutes ago, Originaltwist said:

 

@Andehh - any suggestions for a suitable second hand EV with the right battery please.

I have a Nissan leaf for sale for £4k.  It has 10 out of 12 bars of battery health remaining. 

It's a 2013 so a Sunderland-made one (much better than the earlier Japanese ones), has a 24 kwh battery and has high miles (168k) but has been well maintained and looked after. EV's don't have a lot of components that wear out so it's really just the brakes, suspension, tyres etc that need done every now and then and I've had all that overhauled on mine recently. It has the usual minor parking scuffs from other people's poor parking but they are genuinely minor. I can take more photos or a video if anyone wants one. Also happy to supply the reg in a message. 

 

It's a cracking wee motor, but I just really need a van. It will break my heart to sell it though, I do really love this car. It goes like a rocket and is such a pleasure to drive. I get 70-80miles range when fully charged, dependent on outside temperature. It's in Hawick in the Scottish borders, but I could meet in Carlisle or Edinburgh and take the bus back home if that worked for someone. 

 

 

 

[AliG]

13 hours ago, Dillsue said:

I'm guessing that Octopus have a cunning plan for this but seems there's no approved Wallboxes on the ENA inverter database.

I'm not sure the Wallbox Qasar charger they mention is still made. Wallbox have announced a V2 version but it is not available yet.

 

The V1 charger Wallbox Qasar V2G charger was a preposterous £3950 meaning that all the benefit would be accruing to Wallbox. Looking at the cost of inverters there is no justifying this price.

 

I was originally worried about the impact on the car battery but having looked at it further am less concerned.

 

Car batteries are generally considered to be good for around 1000 cycles. This would be 2-300,000 miles. Of course the odd battery will suffer premature failure but in reality other parts of the car will probably give up the ghost before the battery. I found the data on the average mileage cars in the UK do before being scrapped. Very few make it past 200,000 miles.

 

I think they will only be allowing around 10kWh per day between the battery and the grid. This is consistent with the 333kWh a month limit and the 13kWh capacity of a Tesla Powerwall for example.

 

Assuming an average battery size of 80kWh, then you would use 45 battery cycles per year. Over 10 years of constant use this would reduce the lifespan of the battery from around 300,000 miles to 150,000 which is probably around the useful life of most cars. Further the batteries don't just stop working, it would simply increase degradation. Arguably it would be more of anise for a car with a smaller battery of around 50kWh where you could be using 70+ cycles a year. I would feel more comfortable using it with a 100kWh battery or having a import/export limit based on the size of the battery.

 

[markharro]

I'm in Edinburgh!

 

We are looking to have an EV charger put in. I was going to get the Zappi installed but what I would really like would be to install a two-way charger to future proof things just in case we do get a car in the future that is capable of essentially being used as a home battery. Interestingly, myenergi are hinting that they may release such a charger at some point in the future - https://support.myenergi.com/hc/en-gb/articles/15196766224273-What-is-Vehicle-To-Grid-V2G-Can-we-do-it

 

Your car has a battery with about twice the capacity of for example a Tesla powerwall but for about half the price. Is it worth buying just to station permanently in the drive as a battery for the house? What I don't understand however is whether it would be compatible with our three-phase connection and whether we would need any further kit other than the specialist charger which seems to be currently unavailable and quite expensive?

 

 

[Square Feet]

1 minute ago, markharro said:

I'm in Edinburgh!

 

We are looking to have an EV charger put in. I was going to get the Zappi installed but what I would really like would be to install a two-way charger to future proof things just in case we do get a car in the future that is capable of essentially being used as a home battery. Interestingly, myenergi are hinting that they may release such a charger at some point in the future - https://support.myenergi.com/hc/en-gb/articles/15196766224273-What-is-Vehicle-To-Grid-V2G-Can-we-do-it

 

Your car has a battery with about twice the capacity of for example a Tesla powerwall but for about half the price. Is it worth buying just to station permanently in the drive as a battery for the house? What I don't understand however is whether it would be compatible with our three-phase connection and whether we would need any further kit other than the specialist charger which seems to be currently unavailable and quite expensive?

 

 

I honestly don't have answers for you other than to say that my car can be charged from a 3 pin plug socket and would come supplied with the cable for that. It's free road tax for EVs so keeping it as a battery that could also be driven if needed would only cost you the insurance and annual MOT. I pay roughly £1 a day for insurance.  I forgot to say that mine has MOT till October. 

[MortarThePoint]

14 minutes ago, AliG said:

Very few make it past 200,000 miles

 

That must make me an elite motorist then 🙂

 

Might you void the warranty of the battery by doing this though?

Edited February 20 by MortarThePoint

[AliG]

10 minutes ago, markharro said:

Your car has a battery with about twice the capacity of for example a Tesla powerwall but for about half the price. Is it worth buying just to station permanently in the drive as a battery for the house? What I don't understand however is whether it would be compatible with our three-phase connection and whether we would need any further kit other than the specialist charger which seems to be currently unavailable and quite expensive?

The Qasar looks to be single phase as it is a 7.4kW charger. The Qasar 2 is 11kW but mentions 48A which is the US single phase way of getting 11kW so still may not be 3 phase.  It may not be necessary to be 3 phase as the phases are netted off against each other for billing purposes. 3 phase would simply increase the amount you could import and export to the grid at any one time. As the amounts of energy being talked about are quite small 3 phase probably wouldn't be necessary.

 

It may be that this kind of box would be unnecessary if the car includes V2L technology. My new car can supply 3.6kW so might not need this expensive box.

 

My Tesla charger broke and I am waiting to see if all of this means I should get a different kind of charger. In the meantime I am using the granny charger and bought a cheap used Tesla Wall charger as I could easily switch it over myself.

 

But really when you are talking about saving £2-300 a year versus Intelligent Octopus, this is a non starter if it requires a multi thousand pound charger. You'd be as well buying a Powerwall or other battery system which wouldn't cost much more, would be permanently available and could be used to time shift on IO providing a much better return.

[AliG]

8 minutes ago, MortarThePoint said:

Might you void the warranty of the battery by doing this though?

Fair question.

 

Most cars do not currently support V2G so the warranty doesn't mention. The warranty is generally 70-80% of capacity up to 8yrs/100,000 miles or something similar.

 

If someone sells a car boasting V2G it will be pretty embarrassing to then exclude it from the warranty.

[SteamyTea]

3 hours ago, JohnMo said:

Did you see the top gear episode here they tested a used Nissan Leaf

Yes.

It would have been worse if the battery had just 'worked' as the Apple Generation says.

I am sure I can get my car to do 20 MPG if I want to, instead of 65 MPG.

[AliG]

The original Nissan Leaf had no battery thermal management ad is well known to have many issues.

 

It is not comparable at all to a newer EV. It was introduced in 2010, the same year as the iPhone 4.

 

We literally just bought a Kia EV9 to replace my Model X, but I am seriously considering keeping the X as it is in excellent shape.

 

The X is a 2017 75D with 39,000 miles on it and last time I looked showed 4% battery degradation. Other parts will give out long before the battery.

[Dillsue]

20 minutes ago, AliG said:

It may be that this kind of box would be unnecessary if the car includes V2L technology. My new car can supply 3.6kW so might not need this expensive box.

With V2G/H the car becomes a generator and if you want to connect it to the grid or grid connected house then the charger/inverter has to comply with all the requirements of G98/99. V2L isn't intended to connect to the grid so doesn't have all the G98/99 functionality

[Square Feet]

5 minutes ago, AliG said:

The original Nissan Leaf had no battery thermal management ad is well known to have many issues.

 

It is not comparable at all to a newer EV. It was introduced in 2010, the same year as the iPhone 4.

 

The one I am selling is not the original model, it's the next along one that was made in Sunderland - it has the bigger boot capacity for example. Mine has mostly just been charged via one of the slower connections (ie Type 2, 7kw) as this preserves battery health. It had 11 bars of health on it when I bought it three years ago but dropped down to 10 after I took it down south in a heatwave, charging via rapid stations every hour or so along the way. If you stick to Type 2 or even the slower 3 pin plug charging then it doesn't overheat and battery degradation can be massively reduced. It really isn't the sort of car that would be your first choice for a long journey anyway. It's fantastic for shorter journeys and city or town driving though.

[AliG]

14 minutes ago, Dillsue said:

With V2G/H the car becomes a generator and if you want to connect it to the grid or grid connected house then the charger/inverter has to comply with all the requirements of G98/99. V2L isn't intended to connect to the grid so doesn't have all the G98/99 functionality

The EV9 and I think the new Volvo EX90/Polestar 3 say they have V2G technology included. I assume this means that they have a DC inverter which can take energy from the battery and send it back to the grid. They then use this to provide V2L, I was being overly brief in what I was typing.

 

However, things are all a bit vague at the moment so there is no information yet on what other equipment will or will not be needed to get this up and running. For example will it be compatible in all countries. Hence why I am in wait and see mode re getting a new wall charger. However, if I lost IO then it would not be worth it and so it was not in any way a reason for buying the car.