On the DESNZ weekly mailing - Plug in  solar safety study

https://www.gov.uk/government/publications/plug-in-solar-electrical-safety-study?utm_medium=email&utm_campaign=govuk-notifications-topic&utm_source=0c652f54-2f44-4d17-af0b-e223b0ba4fff&utm_content=weekly

I haven't read it in full yet but from the few snippets I have read suggest the study was expressly set the boundary condition that plug in means plug in without the intervention of an electrician and into current UK electrical installations (a 'no-modification boundary' in study terminology). This is, IMHO, the right boundary condition to set by a Government that intends to make this happen unless there are overwhelming reasons why it shouldn't.

The conclusion reads as follows:

• 'The overall conclusion is therefore conditional on excluding devices from the market that don’t meet the defined technical standards for the product category. Safe operation is technically feasible for suitably certified devices and within stated usage conditions, but not all devices currently being sold in the UK meet the required technical standards they claim to be certified against.'

There is a series of 9 recommendations some of which prima facie have implied delays associated with them.  The established industry will presumably use this as evidence for delay; until I read the report in full I don't have a personal opinion whether this would be proportionate or not, nor do I have any insight as to how the Government may react.

This looks to me like a Government doing appropriate due diligence with the level of determination to progress this that we would hope for, but without being reckless.  Im not sure what more we can reasonably ask for.

Further to the above below are some key paragraphs from the report.

In summary I read it as a report that appears to negate (or find ways to overcome) the concerns that have been raised by the established industry, and give a conditional go-ahead on which the Government could likely rely, however there is the potential for limited delay depending on the extent to which some of the recommendations expressed as 'beneficial' (but not essential) are implemented.

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A central feature of the study is the adoption of a strict no-modification deployment boundary.
Under this boundary, devices are assessed in a form intended to reflect the core consumer
proposition associated with plug-in PV: connection to an existing socket-outlet without changes
to fixed wiring, dedicated generation circuits, replacement protective devices, or consumer unit
alterations.

This boundary is important because it directly reflects the policy question under examination.
The study is not asking whether socket connected PV could be made acceptable if
accompanied by conventional electrical installation works or bespoke protective arrangements.
It is asking whether a consumer plug-in model can operate safely and coherently within
representative domestic installations as they are commonly found.

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Products should be accompanied by operationally specific consumer guidance covering
acceptable socket types and minimum condition expectations; the distinction between straight
and coiled extension lead use; the unsuitability of travel adaptors and multi-way extension
leads not rated for continuous generation loads; recommended circuit loading practices; and
the distinction between plug-in PV and permanently installed microgeneration. This guidance
should be prominent at point of sale and within product documentation.

The study does not identify a technical basis for requiring full conventional installer led
microgeneration procedures for all low power plug-in PV systems. However, it does support
the value of clearly defined minimum installation expectations and, in some circumstances,
optional advisory checks where the age, condition, or protective arrangements of the
installation are uncertain.

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The central implementation implication of the study is that plug-in PV systems are compatible
with UK domestic electrical systems when operated within the tested no-modification boundary
and when products meet appropriate technical requirements. The empirical evidence supports
technical feasibility within that boundary, and the relevant implementation question is therefore
not whether plug-in PV can be deployed, but how a proportionate and enforceable product and
notification framework should be designed.

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The study also notes that the position of plug-in PV under Permitted Development Regulations
is not currently clear.40 It is uncertain whether socket connected generation installed on
balconies or external walls falls within existing PDR provisions or requires separate planning
consideration. Resolving this question should form part of the implementation framework, as
ambiguity in planning status could create uncertainty for both consumers and enforcement
authorities.

----------------------

The study findings do not support a blanket requirement for electrician installation within the
assessed no-modification deployment model. However, it does indicate that some households
may benefit from optional professional support where installation condition is uncertain, socket
quality is visibly degraded, protective device arrangements are unclear, or the intended
connection point is not obviously suitable.
A proportionate model could therefore combine a primarily consumer led pathway with optional
or targeted advisory support. This would help preserve the accessibility benefits of plug-in PV,
particularly for renters and households unable to pursue rooftop solar, while still recognising
that not all domestic environments offer an identical deployment scenario.

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The evidence generated during this study indicates that plug-in PV systems can demonstrate
broadly safe and technically coherent behaviour within the strict no-modification boundary
tested. Across the representative domestic circuits, devices generally maintained stable
operation, disconnected appropriately under loss-of-mains and fault conditions, and did not
exhibit sustained unsafe energisation or uncontrolled thermal behaviour in the tested
scenarios.
However, the study does not support the conclusion that all plug-in PV products can be treated
as a fully uniform or universally suitable consumer appliance category for unrestricted
deployment. Product specific variation from existing technical standards was observed in areas
including export limitation behaviour, threshold response under voltage and frequency
excursions, and electromagnetic compatibility performance under the applied conditions.
The overall conclusion is therefore conditional on excluding devices from the market that don’t
meet the defined technical standards for the product category. Safe operation is technically
feasible for suitably certified devices and within stated usage conditions, but not all devices
currently being sold in the UK meet the required technical standards they claim to be certified
against.

------------------------------------

The central question for DESNZ was whether plug-in PV can be safely deployed in the United
Kingdom without modification to sockets or fixed building wiring. Based on the evidence,
deployment appears technically feasible within a clearly defined and controlled framework.
Appropriate product standards and safeguards would therefore be needed to support
deployment.
Those conditions are the no-modification boundary, qualifying product standards, defined
export limitations, and the consumer guidance and notification arrangements described in
Chapter 5

The paragraph above effectively gives conditional go-ahead, at least in my interpretation.

The detailed recommendations do suggest some things that would imply delay 'Further work would be beneficia', I guess it will be a government priority call whether to delay further to do these or just get going as soon as the product standards are sorted.

Posted by: @etchedpixels

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I read through they had found one possible example which was not caused by plug in solar and which doesn't appear possible with plug in solar (as it cuts so fast when grid power is lost).

That misses the point.

There are already tens of thousands of plug-in solar kits installed in UK...
... very often bought illegally from a UK-based supplier.

None of those have certification, and we can't tell how fast they may disengage from the grid when there is a power cut.
Perhaps they might not do so at all if there's more than one unit on the same phase.

Posted by: @jamespa

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The conclusion reads as follows:

• 'The overall conclusion is therefore conditional on excluding devices from the market that don’t meet the defined technical standards for the product category. Safe operation is technically feasible for suitably certified devices and within stated usage conditions, but not all devices currently being sold in the UK meet the required technical standards they claim to be certified against.'

Quite.

And I don't think that's now achievable. It's too late to be excluding devices from the market that don’t meet the defined technical standards.

Posted by: @transparent

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And I don't think that's now achievable. It's too late to be excluding devices from the market that don’t meet the defined technical standards.

Well perhaps if the industry had got on board rather than trying to block it then it would have been achievable. 

But oh no, the established industry wittered on about spurious risks and the market took over. 

Serves them right.  Sorry but I have not one iota of sympathy for protectionism of the kind the established industry has exhibited.

Posted by: @transparent

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There are already tens of thousands of plug-in solar kits installed in UK...
... very often bought illegally from a UK-based supplier.

They were generally bought and supplied legally by a UK supplier. They were not supplied with a plug and were supplied with instructions that they must be wired in and are compliant if used in the way instructed. Only the original Powerstream products many years ago came with a lead with a plug and were recalled and reissued with a lead without a plug, and a lead with a plug in a box saying not to use it.

There is "illegal" stuff about. Lots of it but generally all via temu, amazon marketplace and the like - completely uncertified, unsafe, fake UKCA certs the works. That's because we neither check imports not have any laws to target market places who are taking the proverbial. Nothing to do with plug in solar. In fact just about anything illegal you want except for firearms can be found on most of those marketplaces - heavy crossbows, knives, medical drugs, you name it, as well as unsafe batteries, wire in inverters, solar panels everything.

None of those have certification, and we can't tell how fast they may disengage from the grid when there is a power cut.
Perhaps they might not do so at all if there's more than one unit on the same phase.

That has been extensively tested to EU standards. Because of the way they work and the EU requirements the stuff sold in the UK already meets it's not likely to be a problem.

Random object from Temu - who knows, but it's probably more at risk of simply going up in flames instead like the explody ebike kits.

And I don't think that's now achievable. It's too late to be excluding devices from the market that don’t meet the defined technical standards.

For the mainstream vendors it's easy as they won't want the fall out from a government notice alerting people that all their expensive say Ecoflow kit they bought before it was legalized is in fact a paperweight. There's plenty of leverage. Most likely any minor compliance issues can also be addressed in firmware.

The Temu junk crowd don't care either way and that won't be fixed until the law is changed to force Temu and Amazon and the like to be responsible for the safety of all products listed on the marketplace and to have confirmed the legal identity and qualifications of each seller.

As with the EU however we also botched the CE/UKCA marking scheme so there is no proper central register and process to make those doing certifications accountable if they make it all up. The US did this a lot better.

@etchedpixels @transparent 

To me this highlights the folly of believing you can defeat market forces, particularly when other countries not so far away have 'sorted' it.

If something is available and legal in Germany, most people (including me TBH) will feel more than comfortable using it in the UK provided they are not personally committing a crime.

The UK industry which, it seems, has sought to block this with scattergun scare stories, has ultimately done nobody any favours.  Furthermore the next time they try to block something similar, their credibility will (rightly) be reduced.

I do understand their fears.  Plug in solar will devastate the lower capacity end of the professionally installed market, probably taking out the market for up to twice the actual capacity sold as plug in.  That's how the market works guys, the gravy train which you have so far enjoyed is curtailed, and you will need to adapt accordingly.

Consultation is here https://energygovuk.citizenspace.com/energy-security/plug-in-solar/

Posted by: @transparent

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…. and we can't tell how fast they may disengage from the grid when there is a power cut.

Perhaps they might not do so at all if there's more than one unit on the same phase.

Curious how do g98/g99 inverters guarantee that they will not continue to work when there are multiple ones in the same phase (when the grid is off?)

Posted by: @transparent

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And I don't think that's now achievable. It's too late to be excluding devices from the market that don’t meet the defined technical standards.

I am looking forward to be able to lay down a token PV panel.

Apparently it is needed to be awarded an A epc? 

Posted by: @batpred

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Posted by: @transparent

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And I don't think that's now achievable. It's too late to be excluding devices from the market that don’t meet the defined technical standards.

I am looking forward to be able to lay down a token PV panel.

Apparently it is needed to be awarded an A epc? 

 

You could have a gigawatt of plug in solar, it's not counted on an EPC as it's not a fixed system. I don't believe that is going to change.

Posted by: @etchedpixels

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Posted by: @batpred

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Posted by: @transparent

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And I don't think that's now achievable. It's too late to be excluding devices from the market that don’t meet the defined technical standards.

I am looking forward to be able to lay down a token PV panel.

Apparently it is needed to be awarded an A epc? 

 

 

You could have a gigawatt of plug in solar, it's not counted on an EPC as it's not a fixed system. I don't believe that is going to change.

Ah ok, perhaps an expert will need to wire it? 

Or does anything make it illegal for a consumer to wire a few panels together to make it up to 90v (the minimum pv input of my inverter)? 

Posted by: @batpred

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Curious how do g98/g99 inverters guarantee that they will not continue to work when there are multiple ones in the same phase (when the grid is off?)

The reputable manufacturers basically "throw a stone in the water" and then take measurements to check for ripples.

If there's no ripples, then the stone ended up in the ocean, which is the equivalent of the massive size of the grid.

But if you detect a ripple coming back to you, then your stone must've hit a small pond, like another plug-in inverter.

The tricky bit with using that approach will be to distinguish between a ripple returning from another plug-in solar inverter, and one bouncing off a plug-in storage battery, such as the Indevolt ones.

I'm going to assume that a home with both a plug-in solar kit from Lidl and a plug-in storage battery from Asda should be legal,
whereas having two plug-in solar kits is to be made illegal.

Posted by: @transparent

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Posted by: @batpred

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Curious how do g98/g99 inverters guarantee that they will not continue to work when there are multiple ones in the same phase (when the grid is off?)

The reputable manufacturers basically "throw a stone in the water" and then take measurements to check for ripples.

…

i would have thought they would only put out ac current after they sense one that matches g99. 
When the grid goes off, if there are two on the same phase, i cannot see how they know it is off unless the other inverter (be it battery or solar fed) happens to go off…
It would be useful to examine the test condition and the result for one of those “reputable manufacturers“…