Remote Solar Panel Systems

I had an experience today that is quite frankly bugging me.
As some of you may know, I am a Volunteer Firefighter. Today My Brigade and I responded to a Structure Fire, which in itself is not an unusual occurrence and we were probably due one as it's been a while. Upon Arrival, we found the shed (where the batteries and inverter were located), next to the house totally involved and the dwelling was impacted on the wall next to the shed with smoke rolling out from under the eaves with obvious signs of fire in the roof space. After we had dealt with the fire and I was filling out the inevitable paperwork, it transpired that the most probable cause was an overheated inverter that was part of a remote solar installation as the house was totally off grid.
While I have a conceptual understanding of how remote solar works, I would not rate my knowledge as outstanding, but surely there would be some safeguards in the system to prevent catastrophic failure such as this? The electrical safety regulators will most probably inspect the site and investigate further ( a grey area contract wise that will be fought at a level way above a humble Volunteer Brigade Chief such as me).
I am posting this as I know some of our members are in remote areas, possibly relying on solar in some shape or form and I would hate to see anyone go through the massive loss that this couple did today. Please check your solar installations, in fact all electrical installations and if there is any doubt, please get it checked. What I do know is that it was a fairly warm day and that the inverter and battery bank was in a tin roof, timber walled shed, so it could have been quite a high ambient temperature and that the Inverter was a quality brand (not going to name it ). The system was designed and installed by the owner as this line of work is his 9 to 5 job.
Be safe and if I learn anything that I can share, I will.

Most electronics equipment can cope with 50c ambient temperatures. Quality equipment - 55 to 65c. It depends on who made it, and for what conditions. They tend to shut down in over-temperature situations.

My suspicion is a hot electrical joint in the system - panels and leads, inverter, or battery bank. That would cause a fire.
A ruptured (includes exploded) battery is another possibility.

The report into the fire would be interesting reading. Well for me anyway!

A long time ago I maintained remote solar systems in Papua New Guinea.

Hi Karl, Guys,

I agree with AJ, the electrical joints in a solar panel system need regular checking. The power inverter should be in a sealed fire retarding steel cabinet along with the battery charging system. High current joints expand and contract, that along with corrosion can quite easily cause a fire.

The biggest solar panel danger is the ones with the inverters for each panel mounted just underneath the panels themselves. There has been a number of instances where these have simply overheated and set fire to the building roof. Again bad wiring cannot be ruled out.

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Originally Posted by BaronJ

The biggest solar panel danger is the ones with the inverters for each panel mounted just underneath the panels themselves. There has been a number of instances where these have simply overheated and set fire to the building roof. Again bad wiring cannot be ruled out.

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We have these (Enphase) but the issues around inverter overheating have been over come. They also have the advantage of only moving 240V AC across a roof instead of up to 600VDC. There are ~20000 of these systems installed around the world and they are proving safer than the DC systems having fewer fires and a lover deaths /injury

I have something of an update. Following a more detailed investigation it was determined that the fire was not caused by an electrical malfunction. It appears that a petrol powered air compressor may have been placed too close to a timber wall and the hot exhaust gas has ignited the wall.
It was also noted that the 240V side of the installation was not wired to standard and that the installer did not have the appropriate licence.