Check out my V2G (Vehicle to grid) installation with OVO Energy!

Userlevel 3

Updated on 24/05/22 by Jess_OVO

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I had my V2G installed yesterday so it's been less than 24 hours but here's what happened.

The guys (5 of them) turned up on time and were really nice, and after a cup of tea they started work.

As you can see there is a lot of kit and fortunately it didn't rain.

A word of warning, these chaps can drink tea at an astonishing rate, make sure you have lots of tea bags and a reliable kettle ☺.

The install took about 6 hours in total and they cleared away all the rubbish and left the place clean and tidy. Once the hardware had been installed and double checked for safety etc it was time for the big switch on.

There seemed to be a communication problem between my unit and V2G control but once that was sorted and the latest firmware downloaded we were ready to plug the car in, no bang or bright flash so I assumed all was good.

The car was charging (I made sure it was at 50%ish before the install) and the V2G box started flashing, I was then given a tutorial and demonstration of how the box works and what the buttons do, seems to me that white lights are good, red lights bad. Then a quick tutorial on how to isolate the V2G if the worst should happen and that was that.




As you can see the V2G box is not small compared to a normal type 2 charger.

I then had to access the "App" but it's really a website/portal, I am having problems with that as everytime I log out it wont let me back in until I changed my password, I am waiting for a call back to get this sorted.

But apart from that everything seems to be working as it should.

This morning my car is sitting at 100% SOC and I have exported some electricity to the grid.

But the best bit is this.........






Last night our home wasn't using any power from the grid the car was powering everything.

We had TV, lights etc on as normal, we even boiled the kettle, the car powered it all and we were exporting 3.4 kw to the grid for which we get paid for.

From what I can tell this lasted for 3 hours before the charger went back to "idle" mode (doing nothing) until in the early hours when it topped the car back up.

It has been less than 24hrs so everything is new and it will take a few days to get up to speed but first impressions are good but I won't know what savings I'm making until the end of the month, it's the car powering the house savings plus the export tariff compared to the cost of filling the battery that concerns me.

I would like to say a big thank you to the guys for all their hard work yesterday and to OVO for picking me for this trial.

I will update you in a week or so to let you know how it's all going.

If you have any questions regarding installation or V2G please ask and I'll do my best to answer them.

Cheers for now, Del.



28 replies

Userlevel 7
Great to get some insight on the installation process - 6 hours! 😮
Userlevel 3
Not sure how many hours we're spent drinking tea. 😂
Userlevel 7
Badge +2
I'm not sure this is a "fair test" @Delboy. There really needs to be a lot more of us popping in and testing the power-transfer characteristics whilst using your kettle.

Can we all turn up for tea this afternoon? 😉
Userlevel 3
Of course you can, bring cake. 🍰🍰🍰☕
Userlevel 1
Mine took around 9-10 hours. But there were complications. And tea! Not up and running yet, hopefully next week. There was a fault on the car that the charger revealed and my car had different software than they expected - turns out the 30kWh Leaf has several software variations that Nissan hadn't been very clear about, may have been lost in communications between Nissan UK and Nissan Japan. Mine will now charge/discharge at the V2G at the Indra factory where they make them, so next week hopefully they will push a software update to my V2G and we'll have another go. Great to hear yours went well @Delboy !
Userlevel 3
Congrats on the install, looks like they did a smart job!
Userlevel 7
Ok, I am super jealous of this and your car. I look forward to seeing your review maybe in t months time?
Userlevel 3
Hi all,

Well I've had an interesting couple of weeks, my V2G crashed and died after two weeks of use.

Has anyone else had problems?

I had a situation where the fan on the V2G unit was going at full speed and a red light on the display, the app was saying it was either a hardware fault or no internet connection.
If I turned the box off at the isolator in the garage and few minutes later turned it back on after about an hour or so (I did not connect to the car) it went back to the fan and red light fault.
So i've been without it for a couple of weeks, Kaluza arranged an engineer to come and replace the unit which took place today.
He's just left and I now have a version two box which is now charging the car and appears to be working fine, time will tell.

I appreciate that this is a trial and faults will occur and situations like this are to be expected, I understand my box will be inspected back at the factory and it will help in the improvement of the V2G system.

Can anyone who has had V2G for a while please answer a question?
I have just got my June bill and with the V2G my electricity bill is £20.00 more than last month (before V2G) obviously V2G has charged my car more than usual hence the extra cost, but I can't see on my bill what I've exported to the grid or how much money I've been "paid", am I missing something?

I'll keep you updated on how this box behaves and how things are going soon.

Cheers for now, Del.
Userlevel 4
Hi @Delboy,

Hopefully I can help you with the billing question.

Effectively, at the minute the billing process for your exports isn't quite as automated as we would like it to be. You'll receive your export credits for June on your July's statement, for July on August's statement, and so on and so forth. We are trying to make this better and hope to do so over time.

Let me know if you have any other questions.


Userlevel 3
Hi Hari_OVO

So even though I have a smart meter that sends you my usage info every 30 minutes it's going to take OVO a month to tell me what I've exported to the grid and to reimburse me for the energy I've exported, however, I can look at the App and that tells me what I'm exporting in real time.
Could a page be added to my OVO usage to show what was exported to the grid the previous day at least then I would have an idea of what is happening?

If I'm correct I have just paid you full price for all the electricity I have used in june and you have added 5% VAT to that total, so when you finally work out what you owe me will I get 5% added so I get the VAT back that I have overpaid?

I'm sure if I decided to pay you a month in arrears you would have plenty to say.

How long before what I export is shown on the relevant bill, surely all the data is provided by the smart meter in real time so why can't it be added as the usage is?

I hope i'm wrong but I'm starting to feel like OVO are not playing with a completely straight bat here, there seems to be a lack of transparency and the attitude that us customers can be fobbed off with "we are trying to make this better".

It will be two months before I have any idea of what is going on so I would appreciate some reassurance from anyone as to what savings (if any) are to be had with V2G in the real world.

Cheers, Del.
Userlevel 6
My turn to comment on my V2G installation....and to say I'm absolutely over the moon is an understatement. Not only have they made a superb job but the configuration is twice, if not three times as good as I'd expected...let me explain.

I started with my first Type 2, 6.6 kW charger 2 1/2 years ago when I bought my 30 kW LEAF. That was followed by a Type 3, 6.6 kW charger when I replaced it with the 40 kW LEAF 18 months ago. So when I signed up with the V2G programme I asked if they could possibly retain the type 2 and 3 chargers, should I get a guest visiting who didn't have CHAdeMO connection.

I already had installed a new fuse box full of breakers inside the house. This was connected by armoured and buried cable to the garage where I have another breaker box supplying both the type 2 and type 3 chargers on separate switches, understanding that I could only use one at a time due to a 40 amp max and both chargers being 32 amp. So when Deven did a site visit he suggested a three way switch so that all three chargers were available but only one at a time. I was more than happy with that as I could charge almost any car presently available and on the understanding I only charged one vehicle at a time.

I waited about a week and was surprised to get a visa from Northern Power who upgraded my mains fuse (before the in house fuse box) to 100 Amp and again surprised when the OVO engineer came and upgraded the cable legs between the 100 Amp fuse and the meter. He also put an isolation switch between the mains fuse and the house fuse box.

It all made sense when Dan and Greg came yesterday to fit the charger and detailed their plans.

Instead of taking the power from (and to) the fuse box in the garage, they put the new CHAdeMO charger on a two way switch with the type 3 charger and ran a cable to the house, connecting it between the main fuse and in house fuse box.....this meant I not only had use of either the CHAdeMO charger or the type 3 charger separate to the main fuse box.....but with the Type 2 charger still running off the garage breaker box I could use that one at the same time as either of the others....

If I've lost you it means I'm now able to charge two electric vehicles in my garage at the same time, something I thought not possible without having a second supply to the house. And to make it even better as I'm typing, I'm exporting electricity from my Nissan LEAF to the grid at a rate of 3.2 kWh, presently 5.8 kW after 3 hrs 17 minutes........and still exporting at 6.14pm.

With regards to the installation I couldn't fault any of the individuals who came, in total about 6 people from various companies who were all friendly, knowledgeable and good craftsmen men. However I do have one complaint. despite being pre warned and buying ample tea bags in, on the hottest day of the year..ever, both Dan and Greg drank...water....WATER?...did they not know I was on a meter?....

Despite signing up to this trial over a year ago, it was well worth the wait and I now have the benefit of not only giving something back to the grid but also the ability to charge two electric cars at 6.6 kWh simultaneously....Many thanks to everyone at OVO....

Userlevel 6
3 days usage so far and learn't quite a lot I didn't know before...mostly good and a couple of things perhaps not so good.

Firstly the wall mounted device isn't as quiet as my other 6 kW chargers which are almost has a big fan in and if you've charged using a stand alone CHAdeMO charger in a car park or garage you'll know what to expect....perhaps not as loud as some I've heard but on a still night, if the windows are open then you may not be the most popular of neighbours....

Secondly I assumed it would be an hour at peak period in the morning and an hour at peak period in the evening.....forget that. It downloads at 6 kWh and uploads at 3 kWh. Since Friday afternoon when it was commissioned (now 7.30pm Sunday night) I've downloaded 44 kWh and uploaded 49 kWh....and that's a lot of loading....and it doesn't just do it in one's off and on most of the day, sometimes for hours on end, other times a minute to two and it's both uploads and downloads. Present plug in time is 52 hours 25 mins and the charging time is 11hrs 14 mins so the time uploading or downloading is probably about 20% of the day. Now to me it's not a bother as it's in a sealed garage and completely sound proofed so no one knows it's on....and once the novelty of looking at the app to see how much I'm charging is done I'll be happy.

Thirdly and this one is aimed mainly at LEAF 2 owners.....all this uploading and down loading generates heat, not only in the battery (temperature first thing on the morning is about 25C) but also heats up the garage by a few degrees....not a problem in the winter but in the summer a warm garage prevents the battery from cooling further. The result is if you want to drive a long journey and then charge on a CHAdeMO charger the charge rate will be a lot lower in the summer than the 50 kW rate advertised .....thanks to the extra heat......but on the other hand a bit faster in the winter for the same reason.

First impressions?.....well I'm really pleased with it. The installation was brilliant and I'm really pleased with the amount i'm able to donate to the grid...for a small fee of course but not sure how much that will be yet....I'll have to wait till the end of the month to find that out...
Userlevel 6
I'm now having my first concerns about the probably won't effect the majority of people but it's something I'm getting a little worried about.

I like to go for a run to Scotland occasionally....and when I say a run I'm talking about Edinburgh for a coffee, Aviemore for Fish and Chips and John O'Groats just for the run out. It involves some long journeys and repeated charges over a short space of time. The problem is the more I travel the warmer the battery gets. The warmer it gets the slower it charges. The more it charges the warmer it gets.....etc etc. Eventually an initial first charge of 48 kWh can reduce to as little as 13 kWh when the battery temperature rises from about 15C at start to anywhere near 56C.

Normally before I have a run there is no demand on the battery and so it has about 7 hours in the garage to cool down. Then if I have to charge it over night on Economy 7, it's finished charging by 6.30am and it has a couple of hours to cool down again. The battery temperature is usually within 1 degree of the air temperature outside, even in the garage.

Since last week the battery is in constant use either uploading to the grid or downloading from the grid and the battery has no down time to cool. The heat generated dissipates into the garage which increases the in garage air temperature and reduces the cooling effect. The result is at the time I would normally drive the car the battery is now about 10 degrees above ambient temperature. The outside temperature this morning is 17C but the battery temperature is 27C and when I travel on my journey will arrive at the first charge with an already restricted download capacity.

The only way to test my theory is to try it out and weather permitting I will probably have a run up to Aviemore tomorrow for some fish and chips. I struggled in the heat last week when I popped up and another 10 degrees on the battery is likely to aggravate it even more....I'll keep you posted.
Userlevel 4
Hi @Leo Moran - thanks for all of this really insightful feedback. It's great that we've set you up to have both chargers up and running, and thanks for sharing the pics! Love seeing another install completed nicely.

Regarding your concerns about over-heating, it may be beneficial to set a different minimum charge level and/or ready by time on the days where you're planning on making the journey up to Scotland? If you set a higher minimum charge level, it will export less but you likely have a cooler battery in the morning.
Userlevel 6
Thanks for that Hari, glad you like the photos.

I was considering having a run up to Scotland tomorrow but the weather doesn't look to promising so I think I'll give it a miss. I'll continue with the settings as they are for the moment but when I next intend a run to Scotland I'll take your advice and knock the charge level down.

Really appreciate the advice.

Userlevel 4
Let me know how it goes - just had a look at the weather forecast, don't blame you for postponing!

Likewise if you spot anything else that seems different, let us know as it's all great learning and super helpful for us!

Userlevel 6
One of the things I didn't understand before I signed up to the trial was the way we use electricity and the charger has helped me understand...I just thought you'd take an hour's worth at tea time and breakfast time and give me it back during the night...that's not quite the whole story.

Electricity has to be used when generated or it's lost. It can be stored for later use such as in reservoirs for hydro generation later or in my case, to the battery of my car.

Every time I put the kettle on, watch the TV or type on this computer the power has to be generated and rather than fire up another power station when I just want to boil a kettle, the charger taps into my car and feeds that electricity...perhaps 250 watts for a 5 minute brew of the kettle, into my domestic system without drawing anything from the grid.

Equally when the sun shines brightly and the wind blows there may be more power generated than is presently needed for the grid and so that power will be used to top up my battery even during the day time....

The charger is in constant use balancing out supply and demand both to the grid, to my house and back to the car.

The system is generally sold as a benefit to The Grid whereas it should equally be advertised as a back up supply to my house. (at present if the power goes down I cannot run the house off the car because it's still wired up to the grid and if workmen are working on the lines thinking the power is off they could get a nasty shock from my battery still connected. Obviously in time, after the trial this will change)

I couldn't understand why I couldn't use Economy 7 tariff with the system but for the time being at least I do now. Some times I draw power from the grid and sometimes from the car. Equally sometimes I'm giving power back to the grid that I downloaded at night time at 8p per kWh and some which I downloaded at 16p per kWh. Each electron isn't marked "cheap or expensive" so it's too much at the moment to calculate if I bought the electricity cheap or expensive and to compensate me accordingly. No doubt in future they'll be able to fit that in the programme but one step at a time and getting it to work is the first step...

So with 5 days done and almost 20 kW per day fed up to the grid or used in my house I'm very happy with the trial so far. I've made about £5.50 so far and if it continues this way, based on 300 days out of 365 I should make about £350 a year....enough to pay my electric bill of about £385....when you add on interest at 3/4/5%

Onwards and upwards as Buzz Lightyear says....
Userlevel 6
Latest update after 9 days....

Just thought I'd talk about some of the things they don't tell you when you sign up to the trial.

Firstly the temperature (As already mentioned). Because you start exporting to the grid about 4.00pm till just after midnight and then import to your car (mine is set to be ready by 7.00am) the battery gets warm, in my case about 10c above what it normally is without anything happening to the battery after 5.00pm. This has two effects. The first if you're on a 40/62 kW LEAF is when you travel a long distance the extra 10c will slow the rate at which you successively charge at rapid chargers, not sure how much yet till I test it. This can be addressed..... thanks to Hari above, by changing the time when you want the car to be ready, allowing the battery to cool down. Of course the good effect of having a battery start out at 26/27c is it's the optimum operating temperature which means better miles per kW if you're only doing short journeys.

Secondly degradation of the battery. I haven't been monitoring the battery since I got it but at 3 months old it was showing 99.24% SOH and 114.563 AHr. Some amongst you may know what these figures mean. At the start of the trial and with the car 18 months old, almost to the day, it was showing 96% SOH and 110.820 AHr. Today that figure is 95.94% SOH and 110.750 AHr.

I'm not sure but I think that degradation isn't as bad as I thought it would be and it's at a rate half as much as before. I'd be obliged if someone could confirm that.

Thirdly the way that the trial is priced.... having changed from Economy 7 to full rate for the trial it was confusing when I got two bills for July but realised I had a two year contract previously and the gas contract hasn't changed, only the electric so the three days electric bill was only to catch up.

Now this is where it gets interesting. The small screen I have in the kitchen for the smart meter shows the amount you're exporting to the grid as a negative value...up to 3.4 kWh. Put the kettle on and that value drops to negative 1.4 kWh indicating you are using 2 kWh from the car for the kettle and exporting 1.4 kWh to the grid.. However because the computer can't (yet) differentiate between how much you are exporting (the most I've exported so far is 22 kW) and how much you are importing, it adds the two together and charges you for my daily tariff has shot up from £1.00 to about £5.50 a day making the bill for the month £175 or for the year over £2,000. I believe...and hope...that they then credit you at the end of the month for every kW you've exported to the grid after giving it back to you with 6p each kW....but if you weren't expecting the delay of a month or so to sort this out it can come as a big shock...

As for the trial itself just one little thing. I put the car in the garage and plugged in the charger. I then switched it on and almost immediately switched it off because I wanted to move the car again. The machine froze and wouldn't do anything nor release the charger from the car. I merely switched it off at the main switch, switched it back on and like any computer, it reset and operated normally...

So, just waiting for the end of the month to see what the bill comes to...

With regards to your degradation of the battery, the SOH and AHr are both calculated guesses and they vary up and down from day to day, you'll need to check it over a long period of time before you can see any real results.
I started checking mine once a month but on numerous occasions I'd have more capacity left than the previous month, in my case when I went on a longer journey it always showed a improvement in capacity, likewise swapping to a different charging method also seamed to showed a increase in capacity, I usually charged at 3kw so either charging at a rapid or charging with a standard 13a plug socket would show a improvement. I will say that going on a long journey and using the rapid chargers is suppose to be detrimental to the battery capacity so I'm fairly sure the shown improvement isn't actually an improvement but just a little error in the algorithm used to estimate the remaining capacity.

Userlevel 6
Thanks Chris...

I had a similar view when I checked back over the 18 months and found that it didn't always decrease but on odd occasions actually went, as you say, I'll take it with a pinch of salt.....oh and the Guessometer doesn't always tally with the 100% capacity either. Even when it's in the garage unused and the temperature is the same the range varies between 166 and 155...
I’ve just had the charger fitted but it seems it’s not an always on charger, I used to charge with the 3pin plug and because it was always on the climate chargers set in the car would de ice the car, the V2G charger although plugged in is not on all the time and therefore the car doesn’t de ice on the timers. I had to use the Nissan app to do it which pulled the power from the battery.
Has anyone found a work around for this problem? @Leo Moran @piersjk @Delboy
Userlevel 7
Hey @Karlkb15 doesn't look like some of the other V2G trialists are around right now. I've raised with the team here to see if we can shed any light on this for you.

Hey @Karlkb15 doesn't look like some of the other V2G trialists are around right now. I've raised with the team here to see if we can shed any light on this for you.Hey @Karlkb15 doesn't look like some of the other V2G trialists are around right now. I've raised with the team here to see if we can shed any light on this for you.


Thanks, I noticed today the unit was flashing red after it charged the car back to 100% and the climate control timer was not on. I switched the charger off and on and it went green and the climate timer set in the car came on. Maybe some one can see a fault in the data it sends?

Userlevel 7

Here’s the latest import/export figures for our V2G charges - who here has one? You’re part of this! 

Userlevel 6

Hello All,

Just thought I’d give you an update on the V2G trial.

I took delivery of my 40 kW Nissan LEAF on 29th January, 2018, 23 months ago. The first check I made on the battery’s health was on 1st April 2018 when the car had 1,209 miles on the clock and the battery State of Health was 99.24%

I began the trial on 26th July 2019, almost 18 months after purchase and the state of health was 96.00% and the mileage was 10,990… in 18 months the health of the battery had diminished by 3.24%

For the month of August imports and exports were made every day and the SOH  dropped from 95.96% to 95.78%, 0.18% in 1 month.

Today I have just checked the car and after more than 4 months of importing and exporting almost every day the state of health is 94.8% and the mileage is 11,867 so in the last 4 months the state of health has fallen by 1.16%. I suspect that in the summer when the battery temperature was averaging 25C and the outside temperature averaging 21C the wear and tear on the battery was less than in the last few months when the battery and outside temperatures were considerably less...though I have to admit the joy of going in the garage first thing every morning with an OBDII and LEAF spy in my dressing gown was a lot less tedious in August than in December, hence only keeping records for one month. 

July      Import   107.2 kW      Export 114.1 kW

Aug      Import  661.4 kW      Export 598.0 kW

Sept     Import  639.1 kW       Export 489.1 kW

Oct       Import 671.3  kW       Export  555.1 kW

Nov      Import  537.9 kW       Export 486.0 kW

Total    Import  2,616.9 kW     Export 2,242.9 kW


So in summary constant charging and discharging of the battery using the V2G, based purely on the figures given is likely to diminish the life of the battery 3.48% in one year with a mileage half the average. But using the car alone without V2G would be 2.16% in a year. So the wear and tear on the battery would be 1.32% per year from exporting alone, given that you would have to import anyway.

With V2G, after 8 years (period of warranty) the state of health is likely to be 72.16% with V2G and 82.72% without…..something to bear in mind as the warranty limit is 75%


Clearly this is not a scientific evaluation as I have not checked the numbers every day but I hope it may be of use to some of you out there…