On the twentieth of August, 2019, a retailer took a solar company to court in New York over the panels on its own roofs.
The complaint said fires had broken out on at least seven stores the previous year.
The arrays were not the retailer’s. It had leased the roof space, and the energy company owned, installed, ran and maintained what sat up there.
That arrangement covered more than 240 buildings.
The filing asked the court to have every one of those systems removed.
Fifteen months later the two sides settled instead.
Why 120 times a second matters
Start with the electricity, because a roof array behaves unlike anything else in a building.
Household current alternates. At 60 hertz the voltage passes through zero 120 times a second, and an arc struck across a loose joint is starved at each crossing. Many go out on their own.
Direct current does not cross zero. Once an arc is struck in a string of panels it has no natural interruption, so it can sit there and burn through insulation, through a connector shell, through whatever it is resting on.
The second difference is that you cannot switch it off from below. A panel in daylight is a live source, and opening a breaker downstream leaves the wiring between the modules energized.
Codes have since answered both points, with arc fault detection on the array circuits and rapid shutdown that drops the voltage at the panels rather than at the far end of the run.
The hazard is in the joints.
240 roofs owned by one company and run by another
The split of duties is the part most readers will not expect.
In a roof lease the building owner is not the system owner. Someone else selects the hardware, screws it down, inspects it and keeps it running, often for twenty years, on a roof the owner still insures.
So the people walking that roof every week work for a different company, and the records of what they found belong to that company too.
The retailer had pushed back before going to court. According to the filing it asked for every system to be de energized in May 2018, and the company complied.
The complaint alleged that a further fire broke out even after the systems were shut down.
Ownership and risk sat apart.
3.1 million dollars in repairs at one store
The specifics in the complaint are worth reading as what they are, which is one side’s account under oath rather than established fact.
For a store in Indio, California, the filing put repairs above 3.1 million dollars and merchandise destroyed above 6 million, with out of pocket costs including consultants and lawyers expected to pass 8.2 million.
On workmanship it alleged inspectors had seen negligent and dangerous wire connection practices that were readily apparent at many of the sites visited, and that personnel had in some cases used connectors that did not match the cable.
It further alleged the company routinely deployed individuals to inspect the solar systems who lacked basic solar training and knowledge.
The retailer also told the court that the company’s July response had conceded its inspections identified areas for improvement and opportunities for error correction. That characterization is the retailer’s, not a company statement.
The pleaded claims were breach of contract and gross negligence.
What no court ever decided
Here is the part that changes how all of the above should be read.
Nothing was tried. The two companies announced a settlement in early November 2019, the terms were not made public, and no court made any finding on the allegations, in the way that a solar site or an offshore project gets written up as a settled question.
Their joint statement said safety was a top priority for each company and that both looked forward to a safe re energization of the systems. It contains no admission by anyone.
The solar company did not publicly answer the specific allegations about wiring, connectors or inspectors, and the trade coverage at the time reported it had already reimbursed some of the losses.
Two details get flattened in retellings. The filing said at least seven fires, not exactly seven, and a second large customer separately alleged that a rooftop system had caused a fire at one of its California warehouses.
That second claim was also untested.
What a building owner can actually use
Strip out everything a court never ruled on and a short, dull list survives.
Ask who inspects the plug connectors and the cable management, how often, and whether those reports reach the building owner or stay with the system owner.
Ask whether the array has arc fault detection and rapid shutdown, because retrofits predating those requirements are still on roofs.
And treat the roof as live. The modules are a source whenever there is light on them, which is why firefighters approach them that way, and the settlement report left that physics where it was.
A dispute about rooftop solar ended quietly.
The wiring question did not.
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