Solar Energy Systems installation UK - lack of skills

As I researched Solar Energy systems for over a year now I discovered how little I understood the dangerous realities of Solar installations even though powered at ELV level <50Vdc.  The difference being that you are dealing with a constant current of 50 - 100's A dc.  Average Joe, maybe used to Auto/Truck 12/24Vdc  systems probably sees the system as safe - you dont get a shock (boat owners will disagree).  So the hazards of installing a dc distribution system  within a domestic house and the potential to cause disastrous fires are totally underestimated.  Even the average tradesman electrician will not have sufficient training in such matters in his CPD scheme.

To make matters worse, as a result of a question by a neighbour who want to suggest to his lad that he follow an Electrician apprenticeship, I discovered that my area (SE UK) has no regular Technical College Route pursuing CnG courses.  Apprenticeships are very rare and as a rule focus on training junior managers. 

In short, a young person cannot readily find his way in to becoming and electrical tradesman ( I have to make a distinction between the concept of a Technician here)

When you aggregate the complete installation identifying all physical components, the SLD suddenly becomes quite complex.  ie Going from Panel Arrays > optomisers > cables > marshalling boxes > Fuse links > Isolators > Master Circuit Breaker > Inverter (s) > Battery Bank > Domestic Consumer Unit > Grid resale meter > Master Isolator > standby generator > Auto Transfer Switch, Control and monitoring systems, Emergency shutdown scheme.

When you seen the numerous wannabee hopefuls going offgrid and often their lack of formal technical training they dont realise how dangerous their rough and ready installation is

I can post links to many sources of my concern here if there is sufficient interest


  • Are you thinking of ELV systems typically used in off-grid installs, or grid-tied systems on a house roof?  The latter may have the panels wired in series strings, giving relatively modest currents at more dangerous voltages..

  • Agreed - my PV system runs as several hundred volts d.c., but  only a handful of amps. There's no d.c. distribution system either - d.c. from the panels is converted to a.c. by the inverter (in the loft) - and then everything else is the usual a.c. arrangement that anyone with a copy of the OSG would recognise. It can be more complicated of course, especially with battery systems, but again these can be (and commonly are) self contained with a.c. connections.

       - Andy.

  • Yes ELVs <50Vdc.  IMHO its sheer madness to be involved with MV dc Panel strings - way too dangerous  IMHO in a domestic environment, and we dont have the skilled tradesmen to recognise this type of micro grid nor is there a recognised route to upgrade to this unfamiliar but hazardous system.  Way too many unschooled wannabees playing with fireworks.  It is utter negligence by our Political leaders to allow this to continue.  They only woke up to the hazards of amateur plumbers who didnt understand flammable atmospheres till a few houses were blown up flattened.  Then British gas had to step in a institute proper training courses with local tech colleges.  Where do our Electricians get proper upgrades?  A one man jobber cant afford an apprentice (with all the paperwork and oversight involved). He will only have a family member or friend involved.

  • I would hope that most domestic installs would be done by an MCS approved, qualified electrician.  If nothing else, you'd struggle to get export payments on a DIY system.

    I've checked the logs from my system today.  It has two series strings, and each produced up to about 4A at 350V.  Nothing that an ordinary electrician couldn't handle.  It's well within the limit for LV.

  • Where do our Electricians get proper upgrades?

    There seem to be quite a few courses available - e.g., or and lots of others many based on City & Guilds qualifications - e.g. C&G 2399. Try google.

       - Andy.

  • Octopus Energy recently updated their T&C’s to remove the requirement for an MCS Certificate, The SEG terms already had alternatives to MCS.

    I am aware of two installs without an MCS cert who do get Export payments.

    However, SEG and export are not worth the aggravation for the payback these days.

    In a good amount of cases you can get a far better installation by going to a good quality electrician rather than an MCS installer - the shocking statistics on poor installations would seem to support this. 

  • So, how many accidents and from how many installations? To be worth acting on it has to be a lot more dangerous than falling down stairs, or perhaps being run over, as for normal persons we consider that an acceptable risk.(*)

    I will point out that there are not enough accidents prevented to justify Part P, and I suspect there aren't really enough to justify gas-safe either, certainly when comparing with countries in which no such regulations exist but to suggest removing either would be political suicide, so we are stuck. I'm not sure we want another set.


    (*) most adults approaching middle age will know of at least one person lost in a car crash or similar. Some will know more than one. less than 1% will personally have known someone electrocuted or killed in a gas explosion - it is just so rare it ends up as headline news.

  • Pandora's box has been opened here

    Microgeneration Certification Scheme (MCS)

    Just when you thought that the summary dumping of Part P responsibilities on to the LABC (who had no historical involvement in electrical installations) was a complete dog's breakfast, and IMHO remains so to this day and from experiences of Landlords, widely open to brown envelopes.

    Remember gentlepersons that the domestic electrician's primary skill involves "house bashing - that's a trade term and needs years of experience" - this is not to be deprecated in anyway. The industrial electrician is an elite class holding authentic credentials in order to be allowed on site or employed by a Company.  These persons wouldnt trade their coveted positions for the Solar Wild West country.

    The average domestic electrician is a sole trader operating from home and he has to weigh the costs of trading legitimately against competing with rogue chancers who abound.  You can be a hairdresser today, slap some stick on vinyl flashy advert on the side of your van and carry on as "Instant Electrics".  Here today, gone tomorrow Strawman.

    Given that over half the cost of a Roof Panel installation comes from labour and scaffolding (mandatory ???) you can see that installation persons dont need any electrical certification (maybe half day course on how to use a ladder) and can plug in MC4s (even crimp them up).  We have the dubious practice of a young persons finishing tails under supervision of a "Competent Person"  You get the picture?

    Nowhere in any of this labyrinth of obfuscation is there any requirement for anyone to be properly trained in dc power systems. As a certified and authentic EE (not Power btw) I have spent a year looking at the problems of domestic DIY Solar systems on most of the relevant Forums covering USA/CA OZ EU and the Leisure craft/RV.

    If you want a good example of the kind of hazards you can face then the widely acclaimed site  will surely open your eyes.  Ignore all the bells and whistles of batteries and BMS just look behind at the electrical installation behind it all  and think about kids playing with fireworks with a can of petrol nearby.  The guy is a former IT technician and it shows a superficial grasp of dc power systems  (think of MCBs for solar panel disconnect under full sunshine  an OZ scandal since corrected when resulting in numerous alarming arc flash fires)

    (FYI the ABYC has a long history and wealth of experience  certifying electrical systems on boats, they have their own "Codes" and authorised inspectors to UL standards - if your craft is not signed off you dont get insurance and that limits where you can moor your boat - its quite draconian and there are numerous examples of fire aboard caused by electrical faults)

    There is no credible UK Solar forum to exchange User experience.  We cant even recognise the problem of highly publicised  Escooter fires from faulty products we blithely allow to be imported from Cheap Charlie  see YT  The CE mark is a treacherous joke (meaning China Export)

  • I will point out that there are not enough accidents prevented to justify

    IMHO you need to look at the fallacy of that statement - how do you measure the number of accidents prevented when they didnt happen?

  • I've been looking at this recently. I'm building a house in Scotland, part of the Planning requirement is to have PV panels. (I'd have them anyway). I've had one quote, and , asking around, its a typical, maybe low price, 4kW PV, 10kW battery, supplied and fitted for £8850.

    Now, money is getting tight, so looking around, the same materials, can be bought for £5500. That's some mark up to fit those for £8850, especially as the scaffold will already be up, and the Roofer is fitting the trays to mount them (in roof system). I can fit the panels/inverter etc myself, but need the MCS sign off. Except I no longer need that, as Octopus will allow PV export with just an electricians sign off, no need for the MCS requirement, hence now, I'll be DIYing.

    MCS is also changing this year, there are far too many complaints that their eligibility requirements are too tight, rumour has it that entrance to their scheme is going to be loosened a lot. It's a same scenario in the Heat Pump world, good sole traders are not bothering trying for MCS as the costs and paperwork requirements are far too stringent, so good Designers and Installers are not fitting heat pumps, as they are not allowed to apply for the £7500 grant, yet Octopus/BG et al are fitting them with an awful design (50 deg C flow temperature) that will be fitted cheaply, but will cost the customer a lot more in the long run with their poor performance and increased electric usage.