Check out the latest on OVO's Vehicle to Grid trial here

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Since we sent out our last update via email, we've had a few questions coming back from you on what you'll need to be eligible for the trial. For those of you that registered interest in our V2G trial, you should receive an email update today with the information below.

(For those of you that are just interested in this technology, this is for you too!) :D

So to answer some of your questions, please see below!

The V2G trial - what you need:
- Your Electric Vehicle: We’ve entered into a partnership with Nissan and so the V2G Charger will only work on their vehicles. You’ll need to own, lease, or be the primary named driver on a Nissan Electric Vehicle, with a battery capacity of 30kWh or more.

- Your property: You’ll need to be the homeowner of the property where the install is taking place, or have written consent from the homeowner. You also need to have private off-street parking and a broadband connection.

- Energy Supply: OVO Energy will need to supply your property’s electricity. You can switch to us here, but please be aware that this doesn’t guarantee a place on the trial. Unfortunately the trial will not support Economy 7 or similar time of use tariffs.

- Smart Meter: You’ll need to have a working OVO Smart Meter at your property, and be opted-in to half hourly data sharing. This is so we can optimise your charging and calculate imports and exports to maximise the benefit that you get. You can order one here for free - but again, please be aware that this doesn’t guarantee you a place on the trial. Initially, we will be supporting SMETS1 meters, but we hope to be able to support SMETS2 in the near future.

- Location: Unfortunately, in the initial phase of the trial we will not be able to install a charger in Scotland or non-mainland UK. Also, initially we will not be able to support homes where electricity is supplied by Electricity North West. You can check who your energy supplier is here. We’re working on extending the trial beyond the current areas.

- Other microgeneration: If you have on-site microgeneration, its power output will need to be below 4kW.

What happens next?
We’re going to start contacting people who we believe meet the eligibility criteria in the next couple of months. We will start with a small number of people as we test our processes, but plan to expand the trial shortly after.

And in the meantime, feel free to keep a eye on the OVO forum for all the latest discussions and updates. We will make sure we post any updates as soon as we have them.

As always any comments or questions, get posting below!

Updated 04/03/2020

144 replies

Userlevel 2
I've now been on the V2G trial for just over a month, and thought I'd let people know how it's all going. Before commencing the trial I was required to downgrade my smart meter from a SMETS2 to a SMETS1 and switch from Eco7. This has resulted in a delay in the new meter sending meter readings to OVO and therefore I've not had a bill for over two months, but I've been recording manual readings from the smart meter daily to keep tabs on what it's using and exporting, so should give a good indication of what I expect to be billed.

To help give an indication of usage, we are a family of 4 (4 bed house), with an EV that is used for 5 days out of 7 (roughly 750 miles a month), and an ICE car that is used less often. Based on about 30 days of readings, we are averaging a daily electricity usage of 27KWh and exporting 16Kwh. We normally get a top up charge from the supermarket or car park once or twice a week so the car is not always being topped up by the house overnight. Based on these calculations I estimate that my monthly electricity bill will be a net £25 a month, which is roughly what my electricity was prior to having an EV, so it looks like the V2G is paying for free mileage in my EV and maybe a little more.

We've had a few teething problems with the charger crashing, but these are easily reset by just doing a hard reset on the unit (shutting down and rebooting). The app has played up a few times also.

One thing we have discovered is that if you don't need a 100% battery charge at 7am every morning, it's worth changing the schedule in the app to not set a time the car is needed by. This then allows the V2G unit to export a little back to the grid for an hour or so in the morning (6am-7am), the unit then starts exporting about 4pm to midnight. When it's not exporting to the grid any electricity you use in the house is coming from the grid and not the car battery which I didn't realise before the trial, but seeing as the unit has to convert from DC to AC I can now see why this would not be worthwhile just to power a kettle for 2 minutes.

The unit itself is rather large (much bigger than a Rolec) but has more work to do converting the electricity from DC to AC. It's a bit on eyesore on the front of the house and a tethered cable too. It would be good if future generations of the unit could be designed where the operations of the unit could be fitted nearer the meter box (in our case around the side of the house) and then just a smaller plug type socket where the car is parked.

As mentioned above, due to the meter change I've not yet had a bill or any export credits so await and see on this, but am a bit concerned to hear that the billing is not yet straightforward for people to understand what they have used and exported (just a single line showing export credit amount). This really needs resolving with billing accurately reflecting the meter readings of amount used and amount exported, so people can verify with their own readings from the smart meter. If this can't be incorporated on the paper bill at this moment, then perhaps we can receive an email to show how the export credits are calculated each month.

Overall, I am currently happy with being on the trial, and hope that other vehicle makes can be included in the trial soon, as it appears a bit limited to just Nissan Leafs.
Userlevel 5
A couple of days ago I told you I was going to have the new Nissan LEAF 62 kW demonstrator for 2 days and that I would let you know what it was like on the charger.....well....erm....change of plan.

I picked the car up in Edinburgh and left about 10am. Let me tell you it's a complete game changer. No need to stop on the way to charge, no need to use the economy mode, no need to draught or watch the battery temperature, just unleash the horses and arrive in Hartlepool, 137 miles later with a big grin on my face and 23% left in the enormous battery....that's about 15 kWs...ish.

So, the one thing you have to remember is this is a bigger battery....and not just by 50%. Yes it's gone from 40 kWs to 62 kWs....but that extra 22 kWs is all useable compared with about 35 kWs in a 40 kW battery.....and when you use it you then have to replace it and there lies the problem. That's another 3 1/2 hours on a 6 kW charger to top it up...extra to how long it takes you to do the same with a 40 kW LEAF and so all my time was spent topping up the battery with nothing discharged at all....and though Kaluza say I imported 40.6 kW on 4th, OVO say I imported 68.5 kW....and most of that day was spent in Edinburgh. The sooner OVO and Kaluza talk to each other the better...

With regards to using V2G It depends on the way you use your car, remembering the lowest you can go on the battery is 25%. On the 40 kW battery 25% of the useable capacity is about 27 kWs but on the new leaf that's almost 43 kWs. So, if you arrive home empty then you'll spend most of your time charging and you may find you'll be exporting less to the grid than with the 40 kW car.....however if you're like me, Billy No Mates who doesn't go out in daylight for weeks on end and the car is stuck in the garage all the time then the car will be importing and exporting most of the day....2/3rds to export and 1/3rd to import, that's a potential 43 kWs per day at 30p per kW...or £12.90 a day....minus how much you pay for the juice in the first place.

So....if you're on the Trial and you're getting the new 62 kW LEAF then I'd take off your shoes and socks as well as your gloves and you'll need to work out if your gonna make money or lose it. Personally I came into the trial on the full understanding I was going to be out of pocket but wanted to be involved so everything else is a all I have to do is wait another 3 months till my new car is delivered...then I can give you all a proper evaluation...unless someone else beats me to it....oh and if you are interested in getting one here's an update from yesterday. When I placed my order in July Nissan were giving £500 towards the purchase. They have now upped that to £ the anticipated residual value of the new car has also increased.....looks as though EVs are increasing in value over the years whilst ICE cars are decreasing....

And if anyone wants to know my impression of the new car, drop me a line and I'll reproduce what I posted on Facebook...
Userlevel 2
As the first on the V2G trial I can answer some of the questions.
  1. the export rate per kWh is your standard charging rate plus a premium, which for me is 6p per kWh.
  2. The charger plugs into the Chademo port on the car not the type 2, so changing your car after the trial would need a new charger unless it had a Chademo.
  3. It charges at a max of 6kw but OVO regulate the charge to maintain battery integrity.
  4. It exports at peak grid times and is all automatic.
  5. On the app you can set the min charge level and the time you will need the car. The rest is done for you. Just leave it plugged in.
  6. OVO provide a battery guarantee until Nissan take it back over. Some issue about getting paperwork signed off. Nothing to worry about.
  7. Charger behaves as it should. Still has a few snags which are not issues but feedback on anything unusual gets the tech boys sorting it.
  8. The only issue I can see for people who work - is that peak grid time for exporting is when you go to work in the car and when you are travelling back in the evening. As a pensioner I have flexible working hours. The wife tells me when and what job. I just do what I’m told. Oh to be employed again.
Hope that hat answers some questions.
Message me if you want anything further.
Glad to help.
Userlevel 4
Hi all,

Firstly - thank you all for being so active, and providing such valuable feedback. It's hugely appreciated and it's great to see that it helps newer trial participants like @garystokey understand things that possibly aren't made as clear as they should be up front! It's genuinely fantastic to see so many of you on here giving us useful pointers as to how we can improve.

Let me try and summarise where we are currently at with the billing process...

Currently, as @Delboy has said, you will see your export credits for the current month, when you receive your next statement.

So, if you receive your statement on the 8th of each month, you'll see a line item on that statement referring to 'Vehicle-to-grid Trial Export Credits'. These credits are for all the energy exported in the month previous, as well as the money to cover off the additional energy you would have used (so import unit rate + 6p). As @Delboy has pointed out, we have a bit of work to do here to improve what is displayed so there is more information for you. We're looking in to what we can do here.

However, in the lead up to that first statement Your consumption will rise and this will show on your graphs, as pointed out by @Leo Moran.

Because your device will be exporting, and then re-charging your car battery, you'll be using more electricity, as you'll all have quickly noticed in the first few days of having your charger up and running. In an ideal world, we would be able to show you, on the same graph as above, what the extra is that is being used by your V2G charger, and also how much you are exporting each day.

We're a little bit away from that ideal world right now, so we are looking into a couple of things in the more immediate term to see if we can make things a bit better. These are:

  • Whether we can do something up front to ease the surprise/bill anxiety from that initial rise in consumption.
  • Whether we can simplify the export rate slightly to make it easier to understand what you should expect to receive each month.
  • We want to improve on elements of our content and communications, so that as you say @piersjk, people come into the trial fully aware of what is going to happen.
Hopefully I'll be able to share more on the above 3 points soon. I would also like to re-iterate that while your graphs will show an increase in consumption, and a higher cost, your actual direct debit will not be changed, so the actual amount that you are charged will remain the same.

On E7, @Leo Moran - I don't want to make any promises or give you false hope - but we are spending a fair bit of time thinking and investigating what we can do here, once we have something more to share, we'll post something on here because we would love to get your thoughts.

Again, thanks all - really appreciate the feedback, please do keep it coming!

Userlevel 7
Badge +2
@Leo Moran @Transparent I guess the good learning here is that everyone is entitled to their own views and opinions, so it's great to see you both calling this out in your replies.

Let's remember no-one is here to try and get one over on anyone else, we have freedom of speech and want those with knowledge to share as it's super useful to some people, and indeed us at OVO and whilst you @Leo Moran may not want or need the in depth detail that @Transparent is able to offer, given his knowledge, him sharing this, may well be useful to others that are!

Let's continue to support and share knowledge and each take away from it what we want or need to.

And yes Leo, we are very happy with the level of feedback you and all the others on the trial are providing!! Keep up the good work!!

Userlevel 5
Well it's exactly 30 days from whence I commenced the trial and it's been an interesting month. I suppose if you want to know what the maximum transfer of elecrity is, then I have probably taken that to the limit. Having only done 70 miles in 30 days and the car in the garage, connected to the grid all the rest of the time then the numbers I've collected should give a fair representation of what is involved.

Firstly this is not a scientific record and should not be quoted as true. The whole calculations have been done using LEAF Spy Pro, Kaluza charts and Nissan's own Guessomater. Now, based on the fact a watch which is 5 minutes slow tells the right time when it's midnight or noon...albeit 5 minutes out, the timing is accurate. Equally all the records taken are used with the same instruments about the same time in the same conditions and because they are recorded in a unventilated and insulated garage, they are near enough laboratory conditions....all you have to do is work out how accurate the devices and calculations are in the first place... It should also be noted that over the month I have progressively added different readings to the calculations which didn't seam important initially but became pertinent once patterns emerged, like recording the outside temperature and the range...oh, and leaving the car parked in e pedal mode also knocks about 8 miles off the predicted range.

The very base line is the first time I recored information on LEAF Spy Pro. On 1st April 2018 with 1,209 miles on the clock, the state of health of the battery was 99.24% and on the first day of the trial on 26th July 2019 it was 96%. Today that health is 95.82% meaning in 30 days the health has fallen 0.18% or on average 0.006% per day. ( I understand it's not an accurate way of measuring the state of the battery....but hey ho...) For the AHr reading it was 114.563 in April 2018, 110.820 on 26th July and 110.610 today....having fallen 2.10 in 30 days or 0.07 average per day...

In 30 days I imported 641.7 kWs from The Grid and exported 575.8 kWs to the grid, A difference of 63 kWs or 2.1 kWs average per day which is probably power that was used from the battery to run the house rather than drawing from the grid. There again it could be power that's lost to heat or converting it from AC to DC and back again to AC. The average imported was 21.39 kWs per day and the average exported was 19.2 kWs. Roughly calculated, if OVO compensate me .06p per kW that I export to the grid, that's £34.55p they will (hopefully) pay me back in September and every month. It should also point out that if the figures are correct, this will likely be the maximum I'm going to earn in a month given, once the kids are back at school I'll be going for runs out in the car and the number of evenings it will be available for exporting will be reduced.

During one of the hottest Augusts on record I recorded the battery temperature once it was fully charged to 100% every day, just after 7.00am having spent most of the evening from 4.00pm-12.00pm exporting at 3.4 kWh and 12.00am-7.00am importing at 6 kWh. On estimate the battery was 10 degrees warmer using the charger than not using it and with heat unable to dissipate from the insulated garage, this too was normally 10 degrees warmer than the ambient outside temperature. This insulation of heat had an effect on the battery which wasn't able to cool down below that of the garage, a difference of 2c-5c. Over an 8 day period with the battery average 26.2c the garage average was 21.4c. Over 30 days the battery average was 24.6C. The optimum operating temperature for a battery is estimated by some to be 26.7c but with the guesometer range varying from 172 miles to 182 miles in 8 days I'm assuming that it is also based on the relationship between the battery temperature and the air temperature as the vehicle did not move for a week.

The Charger failed to function on 7 occasions...teething problems expected in the experimental stage so it didn't bother me and as I noticed it fairly quickly it didn't cause a problem, only failing in the early hours on one occasion and a quick boost charge had the battery back to 100%. It was noticeable that the charger tended to fail two days on the trot... Wed 7th/ Thursday 8th, Wed 14th/ Thursday 15th, Sun 18th, Thur 22nd/ Friday 23rd. Not sure if it's just a coincidence or something happens on a Wednesday/ Thursday which effects the grid....

So, the conclusion. having spent the last month playing with my new toy I'll be glad when I can just get back to my old life and start using the car for long journeys again....but anticipate it will start over again when I get a 62 kW LEAF which presumably will give different results. Failure apart, I can now predict just how much energy I have left and how soon it will take to give me 100%. I can set how much I want left (25%, enough to get me to the nearest rapid charger if I'm in a hurry) and how much rebate I'm likely to get in a month. I'm not sure, just from these figures which as I said was very inaccurate...but initially the charger doesn't seem to degrade he battery any fact if anything it appears to slow the degradation slightly though long term and more accurate calculations are for someone else to judge.

Am I happy I signed up to the trial? Yes. What do I like about the trial?...well the £30ish pounds in my arse pocket every month will certainly help with the electric bills...especially as I'm also earring 4% interest on it.....but I'm looking forward to having a lovely warm garage in which to work in the winter, even without using the oil filled radiator.

This ones for @Delboy , @Transparent, @Hari_OVO, @Darran_OVO and Aaron and anyone else who can get benefit...

Many thanks Leo. That is all really helpful.
Userlevel 7
Badge +3

Hi @pixelpefekt - glad you could join us!

As you suggest, too many EVs are unlikely to “crash the grid”. However, charging them at home will cause increased losses at the electricity substations. And unless/until EV owners embrace Time-Of-Use (TOU) tariffs, and technology like the Kaluza Platform, then we will also face significant overheating of underground 440v feeds.

The cable sizes for underground feeds to domestic properties have historically been amazing small. Not only do we rely on diversification (not everyone having electrically-heated showers simultaneously!) but the quiet hours between midnight and 7am have been factored-in to permit cables to cool down again. Overnight charging will no longer allow for that.

As yet there are far too few EV chargers in a geographical area to obtain data on these two issues.

However, there’s a whole lot more to think about than just the functionality of the chargers themselves.

Tell us a bit more about your background and don’t forget to fill in your Forum Profile. Thanks.

Userlevel 5
Because of a few teething problems (which haven't effected my ability to export and import) The charger was replaced this morning and I'm now operating on the new fact I've just had my first slight discharge.....(oo er missus).

One thing to bear in mind though if you don't already know. All the imports and exports are recorded on the Kaluza App and you can see instantly just how much is in the battery, how much you have charged and how much you have discharged, half hourly, daily, monthly and yearly. As soon as the new charger is installed all that data is lost and you have to start again from scratch.

If Kaluza are going to fit a new charger, make sure you have backed up your data. So that I had an accurate record, I backed all mine up this morning before unplugging the car for accuracy.

Userlevel 4
Hi @PeterS -

Good news, we are now able to support your area! And no, you won't be charged for switching tariffs ahead of October.

On your existing charging set up, when our installation partners at Kaluza are assessing your property they will let you know if any additional work needs to be carried out in order to ensure you can use your current charger alongside a new V2G one, while remaining compliant with electrical standards.


Userlevel 7
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Does they mean that it's going to start installation within the next few days or weeks?

@rajan we still don't have set dates for the Vehicle to Grid chargers trial, but you'll be the first to know when we are ready to move to the next stage! 😳
Userlevel 4
Hi @rajan , and everyone else on this thread! It's really great to see the levels of interest in the trial... we are in the final stages of testing before carrying out our first couple of installs relatively soon. With a piece of technology as innovative and new as this, there are always bound to be teething problems that we need to overcome before we can move further forward - I'm sure you've seen the updates on our first smart charger install.

As a result, we are being deliberately cautious in committing to specific installation dates. It's going to be a very slow and gradual rollout initially, but we hope to start moving faster in the early part of next year. We're aiming to start contacting some of you who have registered an interest to do a full eligibility check towards the end of this year.

Until then, thank you for your continued patience. We're aware that this has taken longer than we previously expected, and we are working to make sure we can bring this to as many people as possible in the not too distant future.


Userlevel 3
Hi Leo,
As I've only had the V2G since Thursday it's still all very new but the car powers the house when you're exporting to the grid, obviously you can't be pushing leccy to the grid and pulling it from the grid at the same time.
There isn't a way to choose when you push power to the grid/home from the car it's all done automatically.
Hope this helps, Del.
Userlevel 4
@Leo Moran @NoPoke I can confirm V2G uses DC charging, and it's own inverter rather than the one in the car. The V2G unit does indeed have fans inside it.

R.e. rate of charge - @Leo Moran I believe you've got it right there but I'll try and get some more details!
Userlevel 5
Thanks @Hari...@NoPoke
Userlevel 4
Hi @Leo Moran,

Thanks for this - we totally appreciate it's not ideal and we definitely don't want to replace range anxiety with bill anxiety. We are working on improving this, we are aware its less than ideal and we are aiming to learn and refine processes throughout the course of the trial.

You will receive your export credit each month, which will counter the increased consumption and return your overall costs to normal, however I can appreciate that it is uncomfortable to see your costs and consumption rising before your credit arrives. Your direct debit amount will not change, so the actual amount that you spend on your energy will remain the same, and hopefully start to reduce as your export credits start to roll in.

As mentioned, we are working on improvements here that will hopefully reduce the bill anxiety - we will keep you updated on these.


Userlevel 5
Thanks Hari, I thought you may be working on it and the last post wasn't intended as a criticism, just an observation of a concern you may not have appreciated from the other side of paying the bill.

Thanks for the prompt response.. I being greedy in asking can we have the Economy 7 back as well?
Userlevel 1
just started on the v2g trial had the charger fitted yesterday not had time to set up the app only received it later this evening. So not had chance to use the charger as It could not be commissioned yesterday after the fitting was finished too late in the day. so will be popping on here now and again to see if there are anyone's tips on the use
thanks for putting the question on Leo Moran about the bills gives me an idea what to look out for.
thanks Hari for the reply good to see are looking to better the system
Userlevel 2
Hi @Hari_OVO

There may be a little confusion with the billing side of things which I hope you can clear up for people concerned. I have also recently started on the V2G trial and therefore not had any electricity bills yet. Having looked at my meter I can see there are two readings on the meter by pressing "9", an imported electricity figure and an exported electricity figure.

Could you clarify if our electricity bills for the end of August (first full month of trial) will show a charge for the imported electricity and a credit for the exported electricity. I have read elsewhere that the "trial credits" will be a credited to bills a month in arrears, but not sure if that just refers to the 6p additional credit for exported electricity, or the whole amount of exported electricity (unit rate + 6p).

I believe my electricity bill will be 5x larger than the previous month without any exported electricity credit, and so would be good to warn people in advance if this is the case.

Thanks to @Delboy and @Leo Moran for their excellent comments regarding V2G observations. It's been helpful reading while undertaking the trial myself.
Userlevel 5
Thanks for that Darren and I offer my sincere apologies to Transparent if my comments were offensive, they weren't meant to be. I actually enjoy reading his posts as they give me an insight into a world I and probably most other people are unfamiliar with....however in the interests of "freedom speech" perhaps his posts on here are a bit too informative. A condensed version would be very much more appreciated. Also to bear in mind we live at 2 completely different ends of the country and with numerous on shore and offshore wind farms, a massive solar farm and a Nuclear power station and Gas Power station as well as a battery storage station within 6 miles of my house, our circumstances are probably not the same either.

As for the charger, once again it failed in the early hours, making that twice in two days and 7 times this month.....e mail already sent off...

Thanks again Darren for always the diplomat.

Thanks for your posts which are very informative but I am a newby to this area and have some questions I hope you or others may be able to answer.

I am considering getting a second EV and like the sound of V2G but want to know more about how it actually works. This forum has already provided a lot of good info so many thanks.

If I have a new 60kw Nissan Leaf, will that work or only a 40kw battery?

What if any, other EV’s will work for V2G? If no others, do you have an idea of which manufacturers will have this capability next?

We currently have a new VW E-Golf. Any chance of this working with V2G?

I have a 3 phase power supply at my house. Does this mean that I will have the abilty to charge at a faster rate than 6kw as other normal chargers have told me I can charge at up to 22kw? Any other benefits?

If we get the Leaf, we will have two EV’s so will we be able to have both plugged in at the same time or will I need two chargers? We have not bought a home charger yet as I wanted to explore V2G.

I was reading some of the OVO forum comments on V2G and wanted to ask some technical questions as follows?

How it works

When the car is plugged in and the battery has excess power stored (above the minimum I have set), what power source will be used when someone puts on the kettle in the house? Grid or Battery?

I understand that electricity prices spike in the late afternoon and evening vs the late night early hours. Will my battery charging/discharging take advantage of this and what are these rates and amounts likely to be? See link below showing the variation in wholesale electricity prices in the UK hourly.

Please explain this in detail with examples of rates I might pay/receive with a forecast of the costs I could save.

My house is large with 5 people living in it and high electricity usage. Does this mean I will save more money?

Can you send me a worked example showing some scenarios of how it might work over the course of the year?

How does the OVO offer compare to the Octopus powerloop? One of the things I don’t like about the powerloop is the condition that the car has to be plugged in by 6pm to qualify for a rebate and it is capped at £30 per month.

Does OVO have a one or two page document or website that you can send that explains how it works in detail.

My business is focused on climate change and carbon emissions so I am very interested in this area and sorry if I have asked any silly questions but I am not an expert in this area at all.

Many thanks
Userlevel 5
Hello MikeA,

Firstly I'll leave @Transparent and @Hari_OVO to explain the ins and outs to you. Although Transparent may get a bit technical for me, hence I'm somewhat sarcastic to him, I suspect you are a bit more tech savey than me and you should understand his explanations well. I've met him in person and he's very well informed and I'd take his advice anytime (but don't tell him that).

Having just concluded a full month trial of the V2G charger I'm in a position to answer some of your questions. I also have a demonstrator 62kW LEAF on loan on Wednesday so should be able to give you some answers how it compares to the 40kW...but can only speculate what it's like on the V2G. I'm going to run it from 4.00pm till 7 am (the same as the 40 kWh) just to check heat dissipation..see below for other explanation.

When I began the trial I assumed that the car was only going to be used to back up peak periods so it would take from the car for an hour in the morning and an hour in the evening and give me it back in the early hours when I normally charge the car. I was reckoning on about 9-10 kWh a day....I was wrong in so many ways.

I set the car to be ready for 7.00am every morning and the export to the grid always began at 4.00pm, at 3.4 kWh and ended about midnight. It then began importing at 6 kWh till just about 7 when the car was fully charged. Oddly enough this worked out that it took and gave back to me roughly 75% of the battery capacity or 30 kW (allow me a bit of poetic licence with the numbers here because you don't actually get 40kW out of a 40 kW battery, more like 35 kW useable as the battery won't let you take the last 2kWh out and the charger won't suck out below about 3 kWh...guestomate.).

Since the monthly trial completed this morning (it's the first calendar month I can not only compare prices with but also I can compare it with last summer when I signed up to OVO) I played around with the start time of 7am and moved it back to 2.00am tomorrow and by back calculation the vehicle has begun exporting back to the grid already, not waiting till 4.00pm. I can therefore assume that the grid will constantly take power from the battery, 24 hours a day and will calculate the time to recharge at 6 kWh (remember the last 10% throttles so takes longer to charge) and export at 3.4kWh down to 25%.

So, that gets us to the 62 kWh battery which has several advantages. Firstly it is called 62 kWh because it has a capacity of 62 kWh but an availability to use 60 kWh. (oh and yes I don't know the difference between kW and kWh so please allow me lee way in that). Secondly although it generates the same heat that a 40 kWh battery does when discharging or being used, it generates a third less heat when charging and will throttle less towards the end. That means you can take 45 kWh (probably in reality 42 kWh) out of the battery until it reaches 25% compared with about 27 kWh from a 40 kWh battery. So, doing the maths a car ready to use at 7.00am will charge a bit quicker and export a lot longer so I'm speculating the export will start about 10am instead of 4.00pm.

I can't tell you how the pennies work out till I'm billed next week. I've been told that I'll get 6p back for each kWh I export but as there's a 10% difference between how much you export and import, I suspect it won't be exactly 6p when I have to come to pay for it. There's a couple of reasons for this. Instead of using power from the grid it appears that for just the odd kettle, TV or computer, the house draws from the car battery rather than the grid and it's only when I put on the oven, hob, washer, kettle etc, which takes me over 3.4 kWh that I start drawing from the grid. Secondly the grid is AC and the car DC so when importing and exporting power is lost to the inverter changing to compatibility. There's also heat generated which also uses power. So, if OVO allow me for the extra usage or that's all included in the 6p I'll have to wait for the bill to see....incidentally the way they do it is, I believe, they charge you for how much power you draw from the grid and add that to how much you export to the grid. They then bill you for the lot. However they reimburse you the cost of every kWh you export and add 6p to they bill you at 14p kWh and reimburse you at 20p kWh....

I hope this helps you in some way.

So now we get to the stuff that I can only guess at.

Firstly I've been informed that it's only Nissan LEAFs and EV200s that are present;y compatible with the V2G trial run by OVO for two reasons. Firstly Nissan are involved in the trial and secondly it only uses CHAdeMO at the moment because it's the only system capable of two way transference....

The V2G charger imports at 6 kWh and exports at 3.4 kWh so a standard 32 amp electrical system is OK for this charger. When they installed mine they by passed the main fuse box in the garage which also runs through the house box, and installed a bigger main fuse as the power comes into the house from 80 Amp to 100 Amp and installed another fuse box which serves the charger in the garage. The advantage of this is I can use the V2G charger and my original charger at the same time, so I can charge 2 cars without crashing the fusebox. As you have 3 phase I believe you can run up to 23 kWh on that or two 6.6 kWh chargers....perhaps even 3, at the same time...but I'll let others advise you on that, I'm purely speculating.

With regards to charging 2 vehicles I'm not aware of a single unit which will charge 2 cars at the same time but I have a Type 2, Type 3 and now the V2G CHAdeMO and can use any two of the three at the same time. May be wrong but I think you need 2 separate chargers to charge.

As for Octopus, I'm not familiar with them and didn't even know anyone else was doing a V2G trial so can't comment on it. As for payments, if you're getting a set amount it's different from OVO who allow you to charge as little or as long as you want, all for 6p per kWh. By my reckoning, the most I'll make in a month is about £35 from a 40 kWh car but that's with the car being stuck in the garage all day and giving 75% every day...a 62 kWh LEAF should give a bit more, possibly a third more...

As for the costings, layouts etc, sorry but I'm just a retired person, know nothing about business plans, working models etc, I'll leave that to others to show.

I hope this has answered some of your questions and if there are any other queries you have, by all means please ask, only too willing to help....just don't rely on me for the technical stuff...

I'll be putting on comments about the 62 kWh LEAF and the bills when I've had chance to properly evaluate them both later this week.

Userlevel 4
Hey @Leo Moran,

I'll PM you to discuss the specifics here.

In general, just as a reminder - unfortunately your exports are applied a month in arrears, we are working to try and improve this process but it's not as straightforward as it seems.

In the meantime, your direct debit will remain the same, so your actual payments to OVO will not increase. If this is not the case for you, please do let me know and I will investigate.


Userlevel 5
Thanks so much for sharing, @piersjk, it is very useful for us to get a first hand insight into the trial!
Userlevel 7
Badge +2

Hey @Leo Moran great news on the new Leaf, how exciting!!  


You can but ask… I’ve posted your comments to the team, so will see what they say!