photovoltaic electrical installations (Solar Panels)

[The Colonel]

Has anyone any experience of the electrical installations around photovoltaic panels (solar Panels) and fires therein. A client has had two fires in separate installations involving the electrical equipment in  houses that were incorrectly wired and resulted in the fires. A new company was brought in to put the wiring right and as a belt and braces move smoke detectors were installed in the cupboard with the equipment. Instead of using mains powered battery back up detectors they just installed battery operated detectors which are now needing new batteries and other problems so they are considering removing them.

Has any one come across detectors being installed or not in domestic installations of this kind, is there any guidance on this? I am aware that the overall risk from these installations is no greater that normal electrical installations if correctly installed, serviced and maintained.

In short do you need detectors in with the installation or not? can they take out the existing detectors or should they go for mains with battery backup

[Dinnertime Dave]

There is no "requirement" as such, but a bit worrying that your client has had separate incidents. I assume that the same company installed both systems using the same components.

I have a panels on my roof, the inverter in the loft(I assume this is were the fire started) and isolation switch and meter in the garage. By their nature the risk is in the day when it is generating power. The risk is pretty low, I ve not heard of many fires involving them although I did see this -

http://www.birminghammail.co.uk/news/600-shoppers-staff-flee-longbridge-8115494

For the sake of a ?5 smoke alarm in a house not unreasonable but not a requirement.

PS - happy to recommend a company if your thinking of having them. Knocked ?50 a month off my electric bill + fed in tariff

[The Colonel]

Dave, your right it was the same company that carried out the installation which has since been found to be faulty with the wiring connections in the house and not the panels on the roof. Another company has examined and certified all the installations and carried out remedial work where required.

A look at a BRE article indicates that there is no additional risk from the electrics compared with other electrical installations provided they have been installed correctly, serviced and correctly maintained. The installation of the detectors looks to have been a half hearted job with poor batteries and not mains connected.The legal beagles are involved now so look out.

I agree with you there is no requirement and as there should be no additional risk if installed and maintained where is the need for additional detection and if they do put it in at least use decent kit and installations. Cowboys springs to mind

[colin todd]

See BS 5839-6:2013.

[Fishy]

Interesting article on PVs plus a comprehensive list of references can be found here: http://www.bre.co.uk/page.jsp?id=3211

[SamFIRT]

Dear all

I am currently carrying out MSc- research at the University of Kent into whether PV systems are a recognised fire risk. My research is scheduled to be completed by the end of next year. (I am one of the references quoted on the BRE link).

I would be very interested in any information appertaining to any PV systems that any of you guys come across which have failed in any way to cause a risk of fire, whether just over heating (and specifically which components), to full ignition.

Thanks in advance
Sam

[The Colonel]

Colin, thanks for the pointer, the BS is a little non committal but helpful.

Sam, if I get any more info will pass it on.

[colin todd]

Corporal, did I buy you a dog???  If so please look after it well.

[The Colonel]

Colin, passed the pointer onto a colleague our cat wasn't happy but thanks anyway.

[Daffodil]

I had to do a little research on this a few years ago in an operational role when there was a panic that they were very dangerous.

After much google searching and reading around the subject it would seem that in America there had been some instances of PV cells malfuntioning and due to a build up of debris such as leaves under and around the PV cells these were ignited and this led to the subsequent fire.  How much damage was attributed to the standard american timber construction is a question for someone with far more knowledge than I.

The main issue I had was how to isloate the power.  The isolation switch terminates the power at that point but the PV cells can still produce electricity whilst exposed to light.  The best solution I could come up with was to cover the PV cells to prevent light getting to them.

There were very few examples of the converters being the issue. From what you have described the people that installed the original system were not really competent.  I do agree with Dinertime Dave, for the cost of a detector why not have something to cover a specific risk, I have one in my downstairs toilet where the fuse box is.

[col10]

The battery in my smoke detector at home is mains wired, with a battery and an energy cell,  it gives out its annoying beep, to say that the battery needs replacing when the battery is affected by the temperature drop i.e. at night time, when the central heating has gone off.  If you turn it off at the consumer unit it still beeps.  If you take the battery out it still beeps due the little cell inside it.  If you dont have a replacement battery you have to detach the detector from its base and put the detector in the freezer.  that's the only place where  you cant hear it so you can go back to bed.
I would never have a detector with a battery fitted in a cold roof space. Below a thatched roof ok and in a  roof where the insulation is at rafter level, but not practical on the cold side of the insulation.  I'm a patient man but going into the loft at midnight to sort out the smoke detector, before I'm allowed back to bed, is a step too far.

[Mike Buckley]

The rest of us would turn the central heating on.

[colin todd]

I

The main issue I had was how to isloate the power.  

Surely, this is quite simple.  You just turn the Sun off.  I am confident that LFB would have someone capable of doing that, though it might need authorisation from a group manager or above (or a watch manager elsewhere in the England, but a crew manager in Scotland).

[Mr. P]

Ah! So thats what those big ladders are for then?

[colin todd]

Nah, LFB dont need ladders to switch the sun off.  They just shout loud at their man-servant, God Almighty, and get Him to do the job for them.