And we have it:

DESNZ are now investigating the feasibility of balcony solar.  Good start but please ignore some of the utterly stupid comments ("we don't have plugs on UK balconies" 🤦🏻‍♀️) 

Offstage: [we don't even know how to build balconies in this profiteering, cheapskate country but hey...]

Maybe for 'proper plug-and-play' (as opposed to how we currently wire mini systems into CUs) the answer is not to copy but adapt - find a way to have an interface between mini inverter and distribution grid (I'm being deliberately broad here before y'all jump 😁).

Anyway, it is a necessary step forward - we must find ways to bring tenants and flat dwellers into decarbonisation. And... maybe it will inspire smart designers and entrepreneurs to design a simple system or interface.

As for the £2000 suggestion..... if you are a home owner you can do it much cheaper already including paying a qualified spark for wiring to satisfy building regs . But never mind, it's a step in the right direction. 

Posted by: @lucia

↑

...

Maybe for 'proper plug-and-play' (as opposed to how we currently wire mini systems into CUs) the answer is not to copy but adapt - find a way to have an interface between mini inverter and distribution grid (I'm being deliberately broad here before y'all jump ).

...

Actually I'm going to jump but in the same direction as you, @lucia.

It is an inescapable fact that, on the Continent, it is possible to buy a small, cheap solar PV system, plug it in and supplement one's home electricity supply with the power it generates. It is not, however, possible to do the same thing in the UK. That fundamental inequality is all that really matters; anything else is just fluff. Removing that gap is not going to be achieved by focusing on why it's impossible in this country and I believe we need instead to do what an old boss of mine used to call "taking away someone's reasons to fail" - steadily providing answers to what "can't" be done until all that is left is a pathway to success. Precisely what you're suggesting, of course, by highlighting a bit of judicious adaptation instead of copying.

Ultimately, I find it hard to believe that the collective technological knowhow in the UK cannot come up with a simple way to achieve what's already being done in other countries. Yes, there are differences and therefore different obstacles to tackle but it's not rocket science. And I wholeheartedly agree that all those who don't own a physical roof and/or the wherewithall to equip a roof with solar panels should be offered realistic and affordable ways to live more sustainably.

@majordennisbloodnok 

balcony solar panels are available in UK, search Amazon for them, here’s a site specialising in them

https://solarplanet.uk/the-complete-guide-to-balcony-solar-panels/#IV.%20Installation%20and%20Setup

Posted by: @agentgeorge

↑

@majordennisbloodnok 

balcony solar panels are available in UK, search Amazon for them, here’s a site specialising in them

https://solarplanet.uk/the-complete-guide-to-balcony-solar-panels/#IV.%20Installation%20and%20Setup

Have a read of my previous posts on so-called Balcony Solar (there’s a sum up of the state of play in my older post just above my post today). 

There’s a huge difference between the small UK micro systems that by law still have to be wired in to a Consumer Unit (no big deal not like rooftop solar) and the plug-and-play systems sold in Germany and elsewhere in Europe. 

It’s the latter that DESNZ is now investigating. 

Time to reawaken this topic.

My thoughts are that, so long as it can be made technically safe, it should be legal, not require planning permission and not require MCS.  Basically you should be able to buy it at B&Q (other DIY outlets are available) and install and connect yourself that same afternoon.

I basically can't see what the objection would be provided it can be made safe, which doubtless it can.

@jamespa, I agree but it's looking unlikely that it'll be plug and play in the UK in many homes. 

I think it needs at least five MCS certificates to make it really, really safe! 😉 

Posted by: @jamespa

↑

I basically can't see what the objection would be provided it can be made safe, which doubtless it can

Yes, in theory it can be installed safely...
... but how would you enable Joe Public to know whether the socket it's being plugged into is supplied from an RCD or an RCBO, and whether that RCBO is bi-directional?

There's not even an agreed symbol for a bi-directional RCBO, and mine have no such marking visible, because the information is printed on the side of the unit.

As with so many components in the quest to attain Net Zero, it's the knowledge-gap which is significant.

If such issues can be resolved, then we should be able to come up with a solution within this Forum discussion.

So please don't hold back from making suggestions...
... but they need to be technically sound, and not reduce the safety levels currently enshrined in the IET Regs.

You cant expect Joe Public to know anything about the matters you mention.  So the unit itself must protect

a) Joe Public

b) Grid workers

c) the cable

against risks caused by the unit without degrading (but without any requirement to enhance) the protection provided at the CU.

It would need to work with RCB, RCDs, RCBOs and indeed fuses. 

I don't design this stuff so I don't know if thats possible, but a 13A max output or less, a 30ms trip on earth leakage, together with cut out on absence of grid signal, all provided at the unit, would seem like a good start.  I don't know if this would somehow conflict with the CU protection but can't immediately see why it would.

I don't think that is possible, which is why I described the problem in my post.

The Plug'n'Play inverter could operate ok if plugged into a circuit which has MCBs, fuses protecting it, whether or not there was an overall RCD.

However, if the householder has had an RCBO installed on that particular power circuit, then there's nothing that the inverter can do to detect if it's a bi-directional device.
Thus there remains the risk that the trip-coil will burn out, leaving the sockets unprotected against an earth leakage fault.

a: That's a breach of the regulations

b: the householder won't know that the safety feature isn't operational

All other possible faults I've considered thus far could be detected by tests undertaken by the micro-inverter...
... but I might yet think of a scenario where that isn't the case of course!

Posted by: @transparent

↑

However, if the householder has had an RCBO installed on that particular power circuit, then there's nothing that the inverter can do to detect if it's a bi-directional device.

Does anyone put a bidirectional device other than on a generator circuit (and if so why?), or is it the more usual case of a regular rcbo that bothers you?

If not then the risk doesn't exist in practice only in theory.

Do you happen to know how other countries deal with the risk.  I realise they have different regs but the risks are the same unless the difference in circuit topology is material?

BTW I don't understand how bidirectional rcbos differ physically, as opposed to functionally, from unidirectional ones, perhaps you could explain if you happen to know.

It's only in the past couple of years that bi-directional RCBOs have been available...
... and only a year since it became illegal to fit a standard (uni-directional) RCBO on a circuit which generates/stores.

That means the great majority of RCBOs presently installed are uni-directional, and have been installed in order to provide the earth-leakage protection.
Otherwise, an MCB could've been used.

The risk is genuine, rather than theoretical.

Homeowners who've agreed to have RCBOs installed by their electrician will have done so because they're prepared to pay more for the additional safety it offers.
That will particularly be the case in households with small children or elderly people, who may try to push something into the socket when they shouldn't!

If a 13A socket on that circuit is used for plug-in-solar, then there's a reasonable chance that the RCBO solonoid coil will burn out at some stage.

The householder will have no indication that the 30mA trip system isn't operational.

I have no idea what other countries do about this issue.

The explanation and diagrams which illustrate the problem are over on this topic.