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



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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.
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Thanks so much for sharing, @piersjk, it is very useful for us to get a first hand insight into the trial!
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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 bonus....now 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 £750...plus 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...
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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 one....in 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.

Leo
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Because of a few failures of my first V2G charger, 9 in total, I had a new one fitted last week and has been running OK right up till 4.10 this morning when it cut out. Bit of a bummer as for the first time in ages I had a trip out booked but now have to shelve it due to less than 50% of charge. Such is life and you have to expect a problem or two. In future if I'm desperate for the car the next day I'll use the back up 7 kW charger...

One thing I did notice was there was a sharp drop of 0.5 GW on the national grid when a Gas Powered station dropped out about the same time. It may be a coincidence but wonder if anyone else has noticed spikes around the time their unit fails? The reference I'm using is below...


https://gridwatch.co.uk

Leo
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Have you got any update on this issue @Leo Moran ?

I wonder if Kaluza have used any surge protection devices within their two EV chargers? Does @Ollie_OVO know please?

I've installed several different types of anti-surge units at my house. Here's one which sits close to my off-grid 24v batteries, and prevents any lightning strikes on my wind-turbine or solar PV-panels from entering the rest of the house.


The surge protector is self-healing and conducts any spikes away to earth via a nice thick wire.

It's a compromise to choose an anti-surge device which is fast-acting and has sufficient capacity. These two parameters are in opposition to each other.

For protection against mains-borne surges I prefer devices which start acting at 380v and can sink 40kA of current within 20nS. Here's a pair next to the mains incomer on my Consumer Unit.


The "velocity of electricity" in a copper wire is 2/3rds the speed of light. That means a spike travels about 300mm in the 20nS it takes for my anti-surge device to reach full conductivity.

The trick is to prevent any surge entering the house in the first place rather than try to quench it with tiny suppressors on individual pieces of equipment.
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@Transparent, when they replaced the unit I don't think they replaced any fuses. They didn't come into the house and there's nothing new in the garage Fusebox....having said that, the unit works off the house box not the garage. Don't know if there's anything in the new unit itself...as for the comment, I've had no feedback on it but don't expect anything. It was just a suggestion and observation..

Leo
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I think it's an important observation @Leo Moran, and needs to form part of the feedback to OVO.

I didn't expect OVO to install whole-house anti-surge devices when they fitted the EV Charger. And I think the vast majority of UK houses don't have surge suppression.

However, it would certainly make sense for Indra/Kaluza to have included some fairly good suppression within the EV Charger itself. It has sensitive electronics in close proximity to mains connections with lots of current flowing.

A surge passing through the charger could not only adversely affect its own electronics, but also damage your car. If it was "optional", I suspect most customers would want to ensure it was present!

Having said that, the effectiveness of such anti-surge devices is directly related to how good an earth connection the Charger has.

As we know from raising the subject of earthing when discussing Smart Meter installations here on the Forum, there are plenty of good reasons why OVO haven't wanted to spend their engineers' time resolving inadequate earthing whilst they're on site.

My view is that end-users should be offered a number of other tests and services whilst OVO's engineers are on-site. Fitting Smart Meters, EV Chargers and other intelligent load-devices is a golden opportunity to bring the UK housing stock up to a better level of electrical safety and functionality.

Such a service would also sit well alongside OVO's Corgi packages.

Even if @Ollie_OVO and @Hari_OVO can't yet respond to tell us if the two Indra EV Chargers do contain any surge suppression, I'd still like to know if they've listened to what @Leo Moran has mentioned about spikes/surges being a possible cause of charger failure.

Is this forming part of the feedback to the design team?
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@Transparent @Leo Moran here's some detail from the team, around your questions and comments regarding protection against power surges etc.

The current that goes through the V2G charger is monitored every 100m/s. Any changes to this current that are out of the ordinary, trigger contactors inside the unit to open preventing any additional current (from a surge for example) flowing through. Worth noting, there's a 20 amp fuse inside the charger too linked to the DC side, as an additional measure.
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Thanks @Darran_OVO. So that monitoring system is operating 5 million times slower than the surge protection devices I've opted to install in my home.

Actually it's slower than that because the contactor still has to open to protect the electronics within the V2G charger.

(I love the typo, @Darran_OVO. I now have a lovely image of a couple of electrical contractors who live inside the unit 😉 )

So... back to the physics:

Now we know that the internal protection device is a mechanical contactor, I think @Leo Moran's theory is worthwhile pursuing. His second charger has been fitted a month ago, and already failed. At this stage it would be worthwhile installing a couple of surge-protection devices on the mains-incomer, or a mains logger, or both.

Something's going on... and I'm beginning to doubt that it's an inherrent design flaw in the V2G Charger itself.

@Leo Moran have you considered emailing Northern Powergrid to ask if they have mains integrity logging on their Bulk Supply Points or Primary Distribution Transformers? They might be incentivised to respond helpfully if they knew you were a V2G test-site.
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Typo? @Transparent, what typo?
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Thanks @Darran_OVO. So that monitoring system is operating 5 million times slower than the surge protection devices I've opted to install in my home.

Actually it's slower than that because the contactor still has to open to protect the electronics within the V2G charger
.

(I love the typo, @Darran_OVO. I now have a lovely image of a couple of electrical contractors who live inside the unit 😉 )

So... back to the physics:

Now we know that the internal protection device is a mechanical contactor, I think @Leo Moran's theory is worthwhile pursuing. His second charger has been fitted a month ago, and already failed. At this stage it would be worthwhile installing a couple of surge-protection devices on the mains-incomer, or a mains logger, or both.

Something's going on... and I'm beginning to doubt that it's an inherrent design flaw in the V2G Charger
itself.

@Leo Moran have you considered emailing Northern Powergrid to ask if they have mains integrity logging on their Bulk Supply Points or Primary Distribution Transformers? They might be incentivised to respond helpfully if they knew you were a V2G

test-site.

......Erm....Don't forget @Transparent I sometimes have difficulty tying my shoe laces.....that one went straight over my head but I see what you mean..No, hadn't thought about that but I'll leave that to Harri and co.

Hi all. I’m brand new to the forum today.

I’m a new OVO customer who is waiting for the V2G charger being installed (so far the process has been very slow and I’ve got 5 more weeks to wait).

I want to hear about your V2G experiences thus far? Good/Bad

I’m excited to be joining this trial even though it may not even be much of a financial gain for me as I’ve have to take a more expensive tarrif of 17p/Kw at OVO but I’m hoping it works out when I start exporting [fingers crossed]. Love the idea of diminishing the myth that too many EVs will crash the national grid!

Thanks.

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I’ve popped your post here, @pixelpefekt, this page will offer some insight, I hope! 

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Hi @pixelpefekt - glad you could join us!

As you suggest, too many [color=#70a020]EVs[/color] are unlikely to “crash the grid”. However, charging them at home will cause increased losses at the electricity substations. And unless/until [color=#70a020]EV[/color] owners embrace [color=#703000]Time-Of-Use[/color] (TOU) tariffs, and technology like the [color=#B00020]Kaluza Platform[/color], 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 [color=#C06040]EV chargers[/color] 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.

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@Darran_OVO …..I wonder if you can answer a cheeky query for me….I know it may sound greedy but in this neck of the woods a shy bairn gets now’t.

 

As you know my V2G charger was installed in July and I’ve been running the trial since with constant updates for you. Perhaps uniquely I had the charger installed in my double garage and the main fuse was increased to 100Amps with a second line independent of the house circuit to supply the 6 kWh V2G unit, allowing me to continue using the original type 1 or 2, 7 kWh chargers if need be without any extra strain on the house circuits. All installations were installed and checked by yourselves so that I can use 2 of the 3 units simultaneously with an isolator switch between the other two units so I cannot overload the system.

 

I am waiting for my 62 kW LEAF to arrive in 3 weeks and part of the offer is….I can have installed free a V2G charger by OVO Energy….yep, I know I already have one and probably am not entitled to one under the terms and conditions….but hear me out.

Are you presently running any trials where 2 V2G units are running simultaneously? A lot of people up and down the country have two cars (which was the reason I wanted to keep the extra chargers). The reason I ask is that I have a few options available to me. I could keep the 40 kW LEAF and run the 62 kW LEAF as a second car, alternatively I can make the 2nd V2G charger available to my neighbour...which could possibly answer a problem whereby people who have no off road parking and anywhere to charge their car, could share points, after all if you offered them free charging I’m sure they’d jump at the offer….whilst I took the extra money from the tariffs…..

So, the question is, as it’s offered as part of the package for the new car, could I have a second V2G installed? ( a question, not a request…..unless I can). It would give you the opportunity of testing out another way of generating storage as well as giving an answer to all those times the question is asked “where can I charge the car”?…..I know my neighbour who has a 40 kW LEAF will make good use of it, not to mention another neighbour who’s looking to buy an electric car but with two cars on their drive, no space for a charger.

 

Leo

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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!  

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Thanks Darran

 

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