V2H and V2G
Options
Comments
-
Me again, sorry to labour the point, but thought it might be interesting to post on here an article I popped on the G&E energy thread yesterday:
Storage team primed for Dorset battery
As I said on the other thread, what caught my interest was that this was installed on the distribution network. Obviously batts can support the transmission network, distribution network, or just the end consumer, but batts like this help the DNO, and supply side V2G, or domestic battery export, or commercial business battery export are being rolled out, all over the World as 'virtual powerstations'.
This is not a grumble about my circumstances, which I assume are a mix up*, just interesting background / clarification on the support role that batteries should offer, whereas, if you think about it, PV could be a nuisance during sunny mid days ..... but again, the solution to that, V2G mopping up cheap excess.
*Heard from another V2G'er who got the same issue, but two days later it was all fine!Mart. Cardiff. 5.58 kWp PV systems (3.58 ESE & 2.0 WNW)
For general PV advice please see the PV FAQ thread on the Green & Ethical Board.0 -
HiMartyn1981 wrote: »Seems highly unlikely and also the reverse of the problem as, as I explained, no other PV anywhere near, and V2G is actually a tool to help with high demand (when voltage will be dropping) not low demand export .
[Edit - I should have said V2H too, as that does the same by peak lopping during high demand for that one property, whilst V2G hopefully does it for a small number of additional properties too (per V2G). So both support the DNO and local substation due to their role and export/consumption timings. M]
Prior to this, I spoke to the DNO about a house fuse upgrade (being done next week) and chatted with them about V2G, and they confirmed that it's seen as a potential way to help them, not hinder them, as it would support high demand periods, and potentially soak up low demand SSEG exports.
Also, you seem to have gotten it backwards regarding your comment about my seeing it in isolation, my whole post and discussion with OVO is the exact opposite - as explained, if the local supply lines couldn't cope with 6kW of export, then that would exclude any more PV being installed, of which there is zero (excluding mine), yet a mile to the west where a new build townhouse complex of approx 100 properties has been built, all have PV, and a mile to the east, where there is a lot of older social housing, approx one out of two houses (50 out of 100) have PV.
They're probably being very wary of the potential for peak export when your demand is low, PV is still belting out loads of electrons on a summer evening and a V2G signal is sent to a fully charged car to help support the grid as a whole .... might have been different if the house supply hadn't already been approved for 16A+ of PV by the DNO.
HTH
Z"We are what we repeatedly do, excellence then is not an act, but a habit. " ...... Aristotle
0 -
Hi
They're probably being very wary of the potential for peak export when your demand is low, PV is still belting out loads of electrons on a summer evening and a V2G signal is sent to a fully charged car to help support the grid as a whole .... might have been different if the house supply hadn't already been approved for 16A+ of PV by the DNO.
HTH
Z
Yep, that's the only thing I could think of, despite the fact that the two would never be discharging at high rates at the same time, they may be looking at worst case theoretical, which I can understand.
But ..... the issue then is not 'my' cable as coping with 12kW of theoretical export should be fine as it can cope with nearly twice as much import. So the issue then becomes the local grid, and that's why I find this interesting as an assumption would be, if 'my' local grid with perhaps a couple of hundred houses and one PV system couldn't cope with 6kW more of export*, then shirley, nowhere could?
That's why I added the example of two additional PV systems also being a problem, which seems strange on a reasonably dense suburban area with the latest cabling upgrade only 7yrs ago. Weird!
*Again, need to stress the obvious, that V2G (and domestic batts, virtual powerplant from multiple domestic batts, V2H and V2G) are not aimed at adding to export, but as demand peak reducers. So their impact on the substation and mains voltage, should be one of support. Yes they will push voltage up, but at a time when that is desired.
I hope this is interesting, always good to find out all the problems, issues etc, though I'd prefer if it wasn't me being the Guinea pig.Mart. Cardiff. 5.58 kWp PV systems (3.58 ESE & 2.0 WNW)
For general PV advice please see the PV FAQ thread on the Green & Ethical Board.0 -
Martyn1981 wrote: »
But ..... the issue then is not 'my' cable as coping with 12kW of theoretical export should be fine as it can cope with nearly twice as much import. So the issue then becomes the local grid, and that's why I find this interesting as an assumption would be, if 'my' local grid with perhaps a couple of hundred houses and one PV system couldn't cope with 6kW more of export*, then shirley, nowhere could?
As I said above and have said in other posts, your cable is not the problem and wont be so taking kwh and multiplying it by x y and z doesnt mean anything above the theoretical.
As Z has mentioned the DNO will take a network view and it doesnt really matter what cable is connected to your house, its how the connections to your house matter.
It doesnt matter if 100 houses with PV are built down the road because the network will be built and connected to them to accommodate 100 houses built with PV. You have a legacy network connection which was never built with PV in mind.
Its not the same but consider an analogy of you own house wiring, you have ring mains and spurs and when the estimated load with load factors are taken into consideration you put in another protected circuit or spur. At some point in the future if you want to change any of that you are better upgrading or replacing. You may never use those extra 4 sockets in your living room at the same time or for anything other than usb chargers but the electrician coming to your house has to do a calculation on the potential use of those sockets and replace/uprate accordingly.
I and others have mentioned on here in the past that there are places in rural NI that its pretty much impossible to get permission for household PV. Its all due to the network. The lines can physically cope with it and the output wouldnt be much of an issue but it could. Its the 'it could' bit thats important.
Its why in any post on self PV install Ive mentioned telling the DNO even when you dont have to because it helps them with their planning.
Retro fitting PV V2G etc is a lot more of an issue than planning it in from the start. Newbuilds having the inbuilt capability to do it from the start will also have the associated electricity network installed to cope in future. Most of us are still stuck with the old connection and even if we are connected to the same substation the lines will be different. That is what you have found out.
Experience triumphs theory (as it were).
If you go back to the recent upgrade of 7 years ago that was probably in planning for a year or two or more so you might be looking at electricity local grid designed over 10 years ago with estimates for PV takeup, new houses, etc built into that based on experience from 10 years ago.
As for things changing in a couple of days, well yes, 10 people apply, 2 get told yes, 8 no, one of the yeses pulls out, the next person to ask gets. That bit isnt rocket science. Those are the type of factors which make it a lot more complicated than just multiplying copper diameter by a factor.
Believe it or not Im happy this happened to someone on this forum because it shows there are a lot more factors at play than just saying rollout = number x time. Its a lot more complicated than that and perhaps it just highlights what some of us have been saying about the legacy network being fit for its previous purpose but not fit for purpose going forward. This wont be as easy as a lot of people are making out.
Martyn, if I were you Id sit on it for a couple of weeks until the initial surge of applications dies down then ask again just in case someone has pulled out.0 -
As I said above and have said in other posts, your cable is not the problem and wont be so taking kwh and multiplying it by x y and z doesnt mean anything above the theoretical.
As Z has mentioned the DNO will take a network view and it doesnt really matter what cable is connected to your house, its how the connections to your house matter.
It doesnt matter if 100 houses with PV are built down the road because the network will be built and connected to them to accommodate 100 houses built with PV. You have a legacy network connection which was never built with PV in mind.
Its not the same but consider an analogy of you own house wiring, you have ring mains and spurs and when the estimated load with load factors are taken into consideration you put in another protected circuit or spur. At some point in the future if you want to change any of that you are better upgrading or replacing. You may never use those extra 4 sockets in your living room at the same time or for anything other than usb chargers but the electrician coming to your house has to do a calculation on the potential use of those sockets and replace/uprate accordingly.
I and others have mentioned on here in the past that there are places in rural NI that its pretty much impossible to get permission for household PV. Its all due to the network. The lines can physically cope with it and the output wouldnt be much of an issue but it could. Its the 'it could' bit thats important.
Its why in any post on self PV install Ive mentioned telling the DNO even when you dont have to because it helps them with their planning.
Retro fitting PV V2G etc is a lot more of an issue than planning it in from the start. Newbuilds having the inbuilt capability to do it from the start will also have the associated electricity network installed to cope in future. Most of us are still stuck with the old connection and even if we are connected to the same substation the lines will be different. That is what you have found out.
Experience triumphs theory (as it were).
If you go back to the recent upgrade of 7 years ago that was probably in planning for a year or two or more so you might be looking at electricity local grid designed over 10 years ago with estimates for PV takeup, new houses, etc built into that based on experience from 10 years ago.
As for things changing in a couple of days, well yes, 10 people apply, 2 get told yes, 8 no, one of the yeses pulls out, the next person to ask gets. That bit isnt rocket science. Those are the type of factors which make it a lot more complicated than just multiplying copper diameter by a factor.
Believe it or not Im happy this happened to someone on this forum because it shows there are a lot more factors at play than just saying rollout = number x time. Its a lot more complicated than that and perhaps it just highlights what some of us have been saying about the legacy network being fit for its previous purpose but not fit for purpose going forward. This wont be as easy as a lot of people are making out.
Martyn, if I were you Id sit on it for a couple of weeks until the initial surge of applications dies down then ask again just in case someone has pulled out.
Hiya, I think you've gotten a bit confused again. As I explained (and you agree) I don't think it's a problem with the supply line to my house individually, hence why my posts have all been looking at the issue from a whole system point of view. I'm still not understanding why you keep making an issue of my individual supply line, I certainly haven't?
Obviously in the UK supply lines will differ, and age is also a factor, and this might impact the total number of SSEG's that can be connected.
However, in my case the properties are relatively dense (no properties on the end of a long supply line needing a high voltage), the cabling is all very new, all homes on individual supply lines (all loops removed during the 2012 upgrade), and there is very little PV.
Hence why I commented that if 'my' local grid can't cope with more PV (I'm comparing a 6kW V2G discharging at the wrong time), then there seems little hope for anyone.
It will be interesting to see how real, or not this issue is, and that's why I posted it. Wifey commented on another site, and the responses were spot on stating that they assume 'we are on the end of a long supply line', 'we are rural', 'we have old cabling and houses are on loops with neighbours'.
All 100% perfect responses, but as that's not the case, I thought this might be interesting to one and all, to show that there is still room for unexpected problems, or hopefully, admin issues for a new technology/rollout.
So just to be clear, in case you still don't understand my points - I'm looking at the local network (not my individual circumstances) and wondering (pondering out loud) why a network that would appear to be at the ideal end, be it more PV, or V2G, would struggle. I think that's interesting.
Not sure I understand your comment about a surge of new applications ..... this is not a new scheme, it's been progressing very slowly.
Edit - funny thought, but your last but one paragraph suggests problems with older networks struggling to cope, but has it occurred to you that V2G and smart charging/discharging of domestic batts is a great solution to those problems, helping to absorb excess, or support the grid in times of high demand?Mart. Cardiff. 5.58 kWp PV systems (3.58 ESE & 2.0 WNW)
For general PV advice please see the PV FAQ thread on the Green & Ethical Board.0 -
Martyn1981 wrote: »Hiya, I think you've gotten a bit confused again.
No Martyn, you just dont understand the whole picture.
The IEEE/IET wrote a paper on this exact thing a few years ago, you can go read it if you are a member.
All this stuff V2G, PV etc connected domestically depends on the connection to your house. Its not about the copper or how new the cable is its about the connection from the substation that your house is on and the loads ordinarily carried.
The fundamental point that you and others seem to miss in all this is that you arent supplying the grid, you are supplying your neighbours. (by and large, most substation fuses and distributions are one way). Backfeed into substation transformers is a big issue and why some of us keep banging on about load factors etc.
How many of your neighbours are connected to you depends on a lot of factors, size of houses, types of heating (central/e7/electric fires), types of cooking (gas/electricity) etc etc etc.
If you (and/or others) are already possibly supplying 50% of estimated load on your particular branch from the substation then thats probably it as far as the DNO is concerned.
Im on a branch with 14 other houses, I export a max of 3.2kwh at peak times in summer. I dont know if any other house on this branch will get permission for solar. I may not get away with V2G as well, it depends on the base load to the other houses. Or if I did I would have to pay to run a separate line to the substation so that it could be farmed out to other branches connected to the same substation.
To use your individual example, 6kw may be in excess of what all the other houses in your branch will draw at a given time, only your DNO will know the utilisation figures and connections. They may go out and do some detailed measurement and give the ok at some point in the future but first port of call is usually the branch diagram and estimated load draws.
Everything depends on the branch you are on to the substation and the usage, that will determine any limiting factors. This is very common indeed, the IEEE paper highlights all of this.0 -
No Martyn, you just dont understand the whole picture.
The IEEE/IET wrote a paper on this exact thing a few years ago, you can go read it if you are a member.
All this stuff V2G, PV etc connected domestically depends on the connection to your house. Its not about the copper or how new the cable is its about the connection from the substation that your house is on and the loads ordinarily carried.
The fundamental point that you and others seem to miss in all this is that you arent supplying the grid, you are supplying your neighbours. (by and large, most substation fuses and distributions are one way). Backfeed into substation transformers is a big issue and why some of us keep banging on about load factors etc.
Nope, I haven't missed that at all, and I'm pretty certain almost everyone else chatting on here hasn't too.
[Edit - In fact my posts have specifically talked about it (not as you've claimed missed it), and the mains voltage rising, and tried to set out how the storage side is aimed at local grid peak support, not to increase loads back on the substation ....... but to reduce loads on the substation. M.]
So, once Joe. The reason I thought this would be interesting is that in my example, the local grid appears to be perfect for more PV (which could push up mains voltage), and given it's a dense area of suburban housing, I'd also think it would benefit from some peak demand support.
Your 'reasons' would effectively rule out almost any additional PV installs, almost anywhere, and of course that's not the case.Mart. Cardiff. 5.58 kWp PV systems (3.58 ESE & 2.0 WNW)
For general PV advice please see the PV FAQ thread on the Green & Ethical Board.0 -
I and others have mentioned on here in the past that there are places in rural NI that its pretty much impossible to get permission for household PV. Its all due to the network. The lines can physically cope with it and the output wouldnt be much of an issue but it could. Its the 'it could' bit thats important.
Its why in any post on self PV install Ive mentioned telling the DNO even when you dont have to because it helps them with their planning.
My bold - All grid connected PV has to be notified to the DNO and appropriately signed off. I'm not aware of any 'even if you don't have to' circumstances.
In fact, in the UK our legislation is tougher than some European countries and doesn't allow for the connection of DIY PV, or 'plug n play' PV which is simply plugged into a socket. UK Pv has to be on a dedicated circuit and hardwired to the CU.Mart. Cardiff. 5.58 kWp PV systems (3.58 ESE & 2.0 WNW)
For general PV advice please see the PV FAQ thread on the Green & Ethical Board.0 -
Just a thought, but I was wondering if any of the people on here with grid connected batteries have had any issues with their DNO's when notifying them? Also, do you need to give sustained or peak power figures, for instance the Tesla PWII has an output of 7kW (if I remember correctly) but 'only' a sustained power output of 5kW.
I can certainly see why a DNO would look to the worst case scenario of batts exporting when not wanted/needed, I'm just hoping that there is some commonsense being applied, or potential solutions if not.
Thanks.Mart. Cardiff. 5.58 kWp PV systems (3.58 ESE & 2.0 WNW)
For general PV advice please see the PV FAQ thread on the Green & Ethical Board.0 -
Joe/Mart, that was a very interesting and informative exchange which has made me aware of issues I hadn’t previously considered. I had, for instance, not realised that approval from the DNO could be an issue when installing batteries.
My back dated application to the DNO for my PV, which my installers are handling, is reaching what I hope is a satisfactory conclusion but it has been a battle as the DNO were holding out for a 5.9kw limit.
I would imagine, in the light of Mart’s experience and Joe’s comments, if I told them I was going to install V2G or batteries they would say no.
I imagine there are a few other people like me who might have thought that one could just go ahead and install a battery but will now need to think again.Northern Lincolnshire. 7.8 kWp system, (4.2 kw west facing panels , 3.6 kw east facing), Solis inverters, Solar IBoost water heater, Mitsubishi SRK35ZS-S and SRK20ZS-S Wall Mounted Inverter Heat Pumps, ex Nissan Leaf owner)0
Categories
- All Categories
- 343.2K Banking & Borrowing
- 250.1K Reduce Debt & Boost Income
- 449.7K Spending & Discounts
- 235.3K Work, Benefits & Business
- 608K Mortgages, Homes & Bills
- 173.1K Life & Family
- 247.9K Travel & Transport
- 1.5M Hobbies & Leisure
- 15.9K Discuss & Feedback
- 15.1K Coronavirus Support Boards