Dno workings

warrenb

I have just had a thought. I am having an EV chargepoint installed and it will draw 7.2 kW. I had to give my mpan number so that the dno can be informed.

Now here is my thought. If I wanted to install a 7.2kW pv system I have to apply for permission from the dno and may involve network upgrades and payment for such.
So to draw an extra 7.2 I just have to let them know. But to generate my own 7.2 I have ask permission and possibly pay.
How does that work?

mmmmikey

If you have an EV point installed you are notifying them so they can identify trends, plan for the long term, etc.


If you install solar panels, as well as the above there are additional concerns. In the event of a general power cut, the possibility arises that without the necessary records and isolation infrastructure the power you are generated electrocutes a network engineer and/or causes other issues.


So different issues lead to different processes - it's not just about the size of the wires.


Hope this helps.

Hexane

My installer's opinion was that it works for the DNO because they can ask for large amounts of money when they feel like it. For my install - which oddly enough is almost exactly the 7.2kWp you mention - the DNO initially asked for £1500, although there was no fee for applying. When we said no to that, they agreed to it for free in exchange for assorted detailed circuit diagrams, labelling and photographs.


A cynic might say that there is significant pressure to increase EV rollout, with lack of charging point seen as an important hurdle in that, but by contrast further rollout of PV isn't something that's seen as important. EV rollout reduces "local" pollution (particulates and such) that the government is getting hammered by the EU for exceeding, but PV rollout mainly only reduces overall CO2 emissions.



Looking at it the other way, when the FiT scheme for PV was originally introduced, it was sufficiently generous that a large number of houses connected to a particular substation might conceivably end up installing PV all at once; but at the time the subsidy and availability of affordable electric vehicles was sufficiently limited that it might be expected to happen over a much larger period of time. As has been the case.

warrenb

This is my point. To draw an additional 7.2 is apparently not a problem and just a notification, to supply 7.2 into the system is this big issue and needs payment for upgrades etc.

Sounds like a scam to me.

If I can install something that draws 7.2 just giving notification, then surely I can install somethings that supplies 7.2 with just a notification.

mmmmikey

The issue here isn't the capacity of the network or the ability of the cables to carry the load. Whether you are drawing or supplying 7.2kW the cables, as you correctly point out need to be the same size. So on that basis there is no argument for treating things differently.



However, if you are supplying power (via solar panels or whatever) you are making part of the network live so the DNO needs to know that and possibly install additional equipment so they can identify and manage the network so their engineers can safely work on it. It's just like when an electrician turns off the supply to your house at the fuse box so they can work safely.


That is why you have to notify them and there may (in some cases) be additional costs. It is not a capacity issue, it is a control issue which is different for supplying than drawing electricity. This is not a scam - in the vast majority of cases it is simply a question of notifying them so they can update records.

Dave_Fowler

mmmmikey wrote: »

The issue here isn't the capacity of the network or the ability of the cables to carry the load. Whether you are drawing or supplying 7.2kW the cables, as you correctly point out need to be the same size. So on that basis there is no argument for treating things differently.



However, if you are supplying power (via solar panels or whatever) you are making part of the network live so the DNO needs to know that and possibly install additional equipment so they can identify and manage the network so their engineers can safely work on it. It's just like when an electrician turns off the supply to your house at the fuse box so they can work safely.


That is why you have to notify them and there may (in some cases) be additional costs. It is not a capacity issue, it is a control issue which is different for supplying than drawing electricity. This is not a scam - in the vast majority of cases it is simply a question of notifying them so they can update records.

All solar panel inverters must comply with MCS standards and have anti-islanding circuitry and as such can not generate power when the grid is off. Hence there should be no danger to power company personnel working on the network.

A problem can arise when there are too many people generating large amounts of power with their PV panels and there is a nett export power at a local substation. The substation transformers and regulating gear is often unable to cope with the reverse power flow. The local substations are not always just simple transformers.

Dave F