Plug-in Solar supposedly going to be 'easier'?

Steve Nixon76 said:

connect solar PV panel inverter directly to the mains using a 3 pin plug and socket arrangement

Welcome to the forum.

The obvious difficulty with this idea is the plug and socket. Would you want a BS 1363 plug with 230 V between the pins?

a BS 1363 plug with 230 V between the pins
When its plugged in of course, that's normal and fine from a touch perspective, but if it adds significantly to the available current on the load side of a 32A MCB, now you have all your other loads plugged in to what is effectively a higher rated circuit than originally, but more importantly quite likely with a longer disconnection time 

I'm assuming like the hard wired units, the inverter has to curl up and stop if it detects a total loss of mains, but this may not be as fast as the supply RCD tripping on its own would have been.

I can see the attraction, and as a plug in gadget, its strictly  outside the reach of BS7671, but I agree there is scope for a few unpleasant unintended consequences.
DIY plug-in kits are  already on sale so I am not too sure what the govt is planning to change or why it thinks it has any levers to control this, as I see it, what folk hang out of a window and plug in is pretty much unenforceable.

And in the UK very few buildings have balconies, unless perhaps its a tower block, which is the very sort of place it would not be a good idea to have too much of it as all the problems of reversal of street main voltage drop and voltage rise still apply, 

Anyway, technical wisdom aside, the govt, position seems to be 'Action 2' on this long list.

https://www.gov.uk/government/publications/solar-roadmap/solar-roadmap-united-kingdom-powered-by-solar-accessible-webpage#part-2-actions-to-address-key-challenges

" Plug-in solar ^{[footnote 28]} can provide opportunities for households to adopt solar more cheaply, particularly for those in rented accommodation or flats. Currently, UK regulations do not allow plug-in solar to be used in the UK, but the government is working to explore its potential.

Action 2: Government will conduct a safety study this year with the aim of unlocking opportunities for plug-in solar over the next few years.

Alongside lower electricity bills, there are many extra benefits for householders that invest in rooftop solar. These include improved Energy Performance Certificate (EPC) scores and property valuation. ^{[footnote 29]} But barriers remain."

Personally I think it would be far more to the point to increase (deregulate) the scope of who is allowed to do a properly wired installation and perhaps see if the various processes can be streamlined a bit. This should try to encourage better engineered solutions and discourage this sort of thing by making the savings of the DIY one insignificant rather than by creating new and unenforceable rules.

Mike

PS my German colleagues tell me that the usual Balkonkraftwerk is limited to 800W per socket plugged in, but putting more than one in the same house spread across the 3 phases is "not unknown" ;-) 

Edit.

There are historical reasons we don't usually build houses like this, and I fear planning permission would be an issue.

This sort of thing might be possible on ex-council blocks.

I agree

A commando style socket with recessed connectors would be better then a BS 1363 plug.  There are also the other factors to consider like if this is a DIY job will some of the following be checked first (Not an exhaustive list)

Is it a ring final circuit or Radial

What is the Earth and bonding at origin of install, is the CPC functional

What size cable is being used eg 2.5mm2 CSA or 4mm2 CSA

What is the cable type T&E, VIR or LS0H (Low Smoke Zero Halogen)

Is it a spur of a spur

Does the CU/DB have an MCB making it bi-directional

Does the CU/DB have an RCBO which is bi-directional

If there is a Split load board is the RCD type AC or Type A

Will sticker/label be fitted on the CU/DB and at the point of orig stating secondary source of energy

Will smoke/heat alarm be fitted in that room that is interlinked to the rest of the dwelling

Does the insurance policy for dwelling cover the inverter

Does the Solar PV / inverter have rapid shutdown

Does the Solar PV / inverter addition count as a new circuit or an addition or alteration

Should an SPD Type 2 be fitted in the CU/DB

An interesting debate so far. It cannot be beyond the wit of man to design a plug and socket arrangement which prevents contact from live conductors on both sides, either purely mechanically, or by having an interlock which opens only when the inverter has powered down.

Of course, if they really are intended for balconies, it assumes that there is a socket on the balcony. Failing that, do you trail the cable in through a door, which being ajar, lets all the warm air out and defeats the purpose? Not today, thank you very much!

Now then, do you need to get a pass on an EICR before an MCS contractor will fit solar PV? If not, how do they ensure that the installation is fit to take PV?

The one thing which seems obvious is that these 'balcony' systems are easier than conventional roof systems. Although a limit of 800 W may not be much, it could be a significant proportion of a small flat's consumption and I like the idea that a tenant can take the system with them on moving house.

Leaving aside safety issues, what do you do when you want to sit out on your balcony? Fold them away? Their use must be limited on east and west sides of a building where they will be in shade most of the time, and no use at all on the north side.

An interesting debate so far. It cannot be beyond the wit of man to design a plug and socket arrangement which prevents contact from live conductors on both sides, either purely mechanically, or by having an interlock which opens only when the inverter has powered down.

Of course, if they really are intended for balconies, it assumes that there is a socket on the balcony. Failing that, do you trail the cable in through a door, which being ajar, lets all the warm air out and defeats the purpose? Not today, thank you very much!

Now then, do you need to get a pass on an EICR before an MCS contractor will fit solar PV? If not, how do they ensure that the installation is fit to take PV?

The one thing which seems obvious is that these 'balcony' systems are easier than conventional roof systems. Although a limit of 800 W may not be much, it could be a significant proportion of a small flat's consumption and I like the idea that a tenant can take the system with them on moving house.

Leaving aside safety issues, what do you do when you want to sit out on your balcony? Fold them away? Their use must be limited on east and west sides of a building where they will be in shade most of the time, and no use at all on the north side.

Chris Pearson said:

An interesting debate so far. It cannot be beyond the wit of man to design a plug and socket arrangement which prevents contact from live conductors on both sides, either purely mechanically, or by having an interlock which opens only when the inverter has powered down.

Yes it's already been done, in Germany they have 'Wieland' socket and plugs which do exactly what you describe, covering the connections to prevent contact with exposed conductors and the wall plates have clips to prevent unintended disconnection.

www.wieland-electric.com/.../