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...but I might be willing to add a decent CU on the end of that radial spur in the garage.
This is exactly where my thinking has landed as well. I had a good chat with @pirate-rich about it earlier over coffee, and my electrician is coming out soon to confirm whether it’s actually viable. If it is, it feels like the quickest, cleanest and most cost-effective route for us... I’ve got zero appetite for a full consumer unit replacement.
Rich also threw in a few other smart ideas, so I’ll run those past the electrician too. If they stack up and are compliant, I’ll share them here.
...but I might be willing to add a decent CU on the end of that radial spur in the garage.
This is exactly where my thinking has landed as well. I had a good chat with @pirate-rich about it earlier over coffee, and my electrician is coming out soon to confirm whether it’s actually viable. If it is, it feels like the quickest, cleanest and most cost-effective route for us... I’ve got zero appetite for a full consumer unit replacement.
Rich also threw in a few other smart ideas, so I’ll run those past the electrician too. If they stack up and are compliant, I’ll share them here.
The G98 distribution code and BS 7671 wiring regulations are being updated for the launch. Be interesting to see if this impacts what the electrician recommends.
The G98 distribution code and BS 7671 wiring regulations are being updated for the launch.
There are two parameters defined within the G98 regulations which already aren't applied to generation devices of 800w and below. These are:
Limited Frequency Sensitive Mode (Over frequency)
Constant active power output
That's been the situation since May 2016 when G98 replaced G83.
I checked the rules with a Standards Engineer last year, and he explained:
The history / concept of this derogation relates to the European rules / standards – the Requirement for Generators (RfG) which stipulates that the scope of the document shall apply to any generator that is considered to be significant and article 5 of the RfG details that where the voltage is less than 110kV and where the capacity does not exceed 800w, the generator is not deemed to be significant.
So that's the reason why Balcony Solar is currently being classified as 800w and below. We are basically harmonising with EU grid regulations.
G98 presently requires generation devices to be 'fixed' (hard-wired) with lockable points of isolation.
For ground-mounted solar panels there must be earthing provided by a means other than the household earth, and it should extend to the metalwork of the PV frames. That's not a requirement for roof-top panels because they can't be touched.
There is also a requirement for G98 installations to have a suitable protective device. Since solar inverters have a DC-component which is 'inserted' onto the mains, the trip must be one which isn't rendered ineffective by that DC component.
Whilst I appreciate these rules will be altered in order to make it legal to use plug-in solar micro-inverters, I still can't see how any of this could be enforced.
What proportion of existing Balcony Solar kits in UK do you think already satisfy these G98 conditions? My estimate is None.
This post was modified 4 weeks ago 2 times by Transparent
What proportion of existing Balcony Solar kits in UK do you think already satisfy these G98 conditions? My estimate is None.
Which may well be a benefit of legalising it. Whilst its not legal only the scammers will sell. Once it is legal then people who are not scammers will pile in with conformant product!
4kW peak of solar PV since 2011; EV and a 1930s house which has been partially renovated to improve its efficiency. 7kW Vaillant heat pump.
What proportion of existing Balcony Solar kits in UK do you think already satisfy these G98 conditions? My estimate is None.
The EcoFlow micro inverters, the smaller 600W and 800W variants which are used for these kind of balcony solar applications, are listed as compliant with current G98 requirements, they're listed on the ENA's equipment database:
The EcoFlow micro-inverters are G98 certified in so far as their on-the-bench functionality is concerned.
To retain compliancy they must then be installed by a qualified electrician because they should be hard-wired with a lockable isolator and a Type-A or Type-B RCD (or bi-directional RCBO) within the Consumer Unit. The installer must undertake the required on-site tests and notify the DNO within 28 days.
What proportion of the EcoFlow units sold in UK do you think have been installed to satisfy all those criteria?
Or do you think it's likely that they are being plugged into a 13A socket?
The final report on the Spanish blackout has been issued. The conclusion is that renewables were not to blame, but many other factors which added up to lack of overall control being fast enough. Some renewable sources had inadequate control, but so did std generation.
I certainly missed this in the news on the 20th, perhaps what Trump said or did dominated the news. And the fact that it wasn’t a simple “ renewables at fault” headline meant not news. If it’s already been discussed here then apologies for repetition.
2kW + Growatt & 4kW +Sunnyboy PV on south-facing roof Solar thermal. 9.5kWh Givenergy battery with AC3. MVHR. Vaillant 7kW ASHP (very pleased with SCOP 4.7) open system operating on WC
The EcoFlow micro-inverters are G98 certified in so far as their on-the-bench functionality is concerned.
To retain compliancy they must then be installed by a qualified electrician because they should be hard-wired with a lockable isolator and a Type-A or Type-B RCD (or bi-directional RCBO) within the Consumer Unit. The installer must undertake the required on-site tests and notify the DNO within 28 days.
What proportion of the EcoFlow units sold in UK do you think have been installed to satisfy all those criteria?
Or do you think it's likely that they are being plugged into a 13A socket?
Here's the FAQ from EcoFlow's own website:
Am curious
@transparent what are you going to do with the information if some could make an educated estimate of the proportion?
Given you are one of the most informed people on the forum and speak to a lot of people, what is your best estimate of the proportion, warts and all?
The EcoFlow micro-inverters are G98 certified in so far as their on-the-bench functionality is concerned.
Yes, which is important because it demonstrates the hardware has the essential safety functions.
To retain compliancy they must then be installed by a qualified electrician because they should be hard-wired with a lockable isolator and a Type-A or Type-B RCD (or bi-directional RCBO) within the Consumer Unit. The installer must undertake the required on-site tests and notify the DNO within 28 days.
What proportion of the EcoFlow units sold in UK do you think have been installed to satisfy all those criteria?
Or do you think it's likely that they are being plugged into a 13A socket?
Not sure I agree about your comment on the RCD requirement, I'd need to check the Regs but I think that depends on the installation arrangements, need for additional RCD protection of concealed cables and the inverter manufacturer's recommendations, so not always required.
As for what portion of the installations comply with G98, realistically I doubt anyone knows, presumably you would need to know the total number of units sold in the UK and the number registered with the DNOs, to then calculate the proportion correctly registered. I doubt that data is available, or if it is, unlikely to be published.
Not sure I agree about your comment on the RCD requirement, I'd need to check the Regs but I think that depends on the installation arrangements, need for additional RCD protection of concealed cables and the inverter manufacturer's recommendations, so not always required.
Thanks. Please post here what you find in the regs.
Here's what I received from the Standards Engineer who was responding to points I made about Plug-in Solar last year:
Both BS 7671 and EREC G98/99 would require the installation to be completed by a competent installer with sufficient skills and training (approved qualifications).
[...]
The use of protective device – solar installation will emit a small DC current into the AC circuits and therefore the correct choice of RCD is required (the is a risk that a RCD would otherwise become blocked by the DC current / won't work) i.e. the upstream system would generally have to be altered to accommodate the connection of the PV equipment.
what are you going to do with the information if some could make an educated estimate of the proportion?
Given you are one of the most informed people on the forum and speak to a lot of people, what is your best estimate of the proportion, warts and all?
One of the issues I raise in communication with elected representatives (ERs) is that policy decisions are being made
without first looking at the science
and then published/announced without reference to the science
Letters I've received from Ministers (which are written by civil servants) are indicative of them not receiving science-based advice before they make energy policy.
And I have later emails from some of those civil servants which show that they didn't know or understand the science themselves anyway. 😮
I don't want to make that mistake myself.
Even if I agree with the outcome of a policy decision, I still inform ERs of the underlying science, and explain what the outcome will be.
IOW I'm doing what I think the civil servants should be doing. My future credibility relies on that. If ERs detected that I was withholding information because I wanted a particular bias in policy to remain, then they're less likely to ask me for advice in future.
I would imagine they will make a carve out in G98/99 especially for these devices.
Maybe a Belgium style "mini ECIR" to check you at least have decent CSA and suitable circuit and just kind of accept that the potential for 800W overhead on a socket circuit is OK?
My biggest concern is what happens when you think about what some people will do - which is plug in a few of these into an extension or something. Thankfully I've come to the conclusion that actually the product standard will mean the device does some grid impedance simulation on board and will be able to detect this beyond the more usual methods. It's a very separate edge case compared to multiple inverters in neighbouring houses forming their own island together, where the differences in load mean that would almost never happen, and I believe there is even a type test for that anyway.
You can quite easily imagine the inverter measures its own output waveform continuously, detects any DC offset above the threshold.
Germany/Italy is the obvious place to look at, lots of their actual grid went transformerless and there was quite some discussions about that all going wrong!
I can fully see why these announcements can get alot of discussion going; especially if no actual technical pathfinding had happened.
