More than 2.68 million rooftop solar PV systems have now been installed in Australia. But REA Global Director Michael Mrowka has declared that changes to national installation standards are urgently needed in order to defuse a “ticking time-bomb” created by unsafe and poorly designed solar installations.
Mrowka said rooftop solar safety standards, particularly those relating to the controversial DC isolators that were mandated in Australia in 2012, have not kept pace with technology and industry changes.
“One example is the AS/NZS 5033 standard that mandates rooftop solar isolators, which have become the largest single cause of solar fires in recent years,” he said. “Combine that with low-cost Chinese products that can be quite dangerous as they age, especially when poorly installed, and you have a ticking time-bomb that can cause electrical shorts and fires.”
Standards Australia has launched a review of AS/NZS 5033. The draft standard has received more than 680 submissions during the public comments stage, which closed last month.
Mrowka told pv magazine that an update on the installation and safety requirements standard is expected in December. But he is far from confident it will deliver the changes the industry is seeking.
“The safety issue is very difficult because governments have given out so many rebates for what may be potential fire hazards that this could be another pink batts installation debacle,” he said, referring to a government-funded insulation scheme that was abandoned in 2010, following the death of four workers and a string of house fires.
Founded in 2006, REA Global designs and installs solar PV energy generation and storage systems for residential and commercial customers. It installs an estimated 15,000 modules per year. The Brisbane-based company also designs and manufactures solar modules and is progressing plans to establish offices in New South Wales and Victoria.
“We’ve been part of the industry for 14 years and 10 years of that as an EPC company designing, installing and maintaining solar systems,” Mrowka said. “We’ve seen a lot of industry changes and one of the biggest issues in the industry is the application of the current technology which is critical. We’ve got a fundamental flaw where higher voltage systems are being installed with DC rooftop isolators that are not fit for purpose.”
Data provided by the Clean Energy Regulator (CER) shows that more than one in four Australian homes have rooftop solar modules. The market is now on track to eclipse all previous records in 2021. However, that uptake has delivered unintended consequences, with Fire and Rescue NSW statistics showing that PV-related fires have increased fivefold over the past five years.
Isolation switches have been blamed for causing almost half of solar module fires. Mrowka is one of many in the industry who is lobbying against their mandated installation, declaring that the safety mechanism has caused more harm than good.
“They’re not designed to be sitting on people’s roofs,” he said. “If we could change one thing to improve this situation, it would be to mandate rapid shutdown and panel-level monitoring and communication.”
The United States is among nations that are pursuing rapid shutdown capabilities for rooftop solar. Mrowka said it is something that also needs to happen in Australia to avoid the situation in the United States, where some first responders won’t respond to fires at homes with solar on the roof until after dark.
“They understand the risks and they’re not putting themselves at risk, to the detriment of the homeowner whose house is burning down,” he said.
Mrowka said the simple solution is to install a micro-inverter system that does not use high voltage DC. He noted that REA Solar exclusively uses technology manufactured by California-based Enphase, which has rapid shutdown capabilities built in.
“The problem with current solar systems is that when you pull the fuse in the street or you cut power to home, energy flowing from the solar system to the inverter is still live and can’t be circuit-protected,” he said. “We install our solar panels with Enphase micro-inverters which let us circuit-protect the system because it runs 240 volts alternating current from the panels, so the homeowner can shut them down, just as with lights and power in the home.”
Mrowka said it is also important that the industry addresses the lack of education and information provided to consumers regarding the costs associated with micro-inverters and DC isolators, which require ongoing maintenance.
“It’s not us versus them, of AC versus DC, it’s an education thing. If you get a DC system, we’re not saying the thing will catch on fire, we’re just saying that if it’s not maintained, over time you’re at a greater threat of it catching on fire. If you maintain the system, there shouldn’t be a problem but because companies are selling low-cost systems, they’re not providing that awareness to customers that there are maintenance costs involved,” he said. “They’re not telling them the rooftop isolators need to be maintained each year. They are failing to educate the customers. They either don’t understand it themselves or they don’t want to disclose it to the customer for fear of losing a sale. It’s really frustrating the lack of education that’s being provided in the industry.”
In addition to its rooftop solar focus, REA Global is also pursuing projects in the electric vehicle space. Mrowka recently took delivery of a new Porsche Taycan, for example. As an experienced driver, he said he plans to race the car, which will be powered entirely by solar.
“It can do a quarter mile in 10 seconds,” he said. “It blows everything away. We plan to do some promotional events and racing to raise general awareness that the future of motorsport will be green and electric.”
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People could benefit from a schematic drawing. How does the concept of a isolation switch differ from the alternative. The fire department should be able to isolate each individual panel from it’s generating capacity, like a kill switch to ground. This would eliminate any presence of DC voltage. This feature will increase the manufacturing cost, the safeguard of physical injury is mandatory and not negotiable.
Where would installer get training to install the PV system in accordance with the safety standards mentioned in this article?
I just had Soler installed on my roof I asked for German panels and inverted Controls from Germany when wind blew down powerlines my investor went dead after a few hours it came back on again but on the app I monitor power input only gives 4kw per hour how do I get it above this I have found battery which will last 10 hrs
DC isolators are an issue, I’ve had a friend that had a gen3 isolator (that was part of a 201 recall (https://www.cleanenergycouncil.org.au/industry/products/product-recalls) and melt down, lucky it didn’t cause damage to the panels, invertor or home, the system was installed in 2014 and the catastrophic fail happened the beginning of this year. I’m an electrician and can say those things get hot from the electric current that flows through them plus they bake in the Australian sun year after year with minimal protection they are a hazard!.. And are you really are you going to climb onto a fireball roof to isolate the hazard in the event of a fire??? Try doing that, especially on a double story house. I understand they need to be close proximity to the rooftop system, but I would see a better solution if they were mounted as close as possible on a wall, shaded if possible
The article about unsafe solar systems would be much more valuable if it described, with photos, the elements that are the danger. Alternatively, if the author could offer more detailed information so everyone could be more certain that any maintenance organisation they engage were effectively and correctly identifying/fixing a problem on the roof and not just taking your money. Otherwise, greatly appreciate you publishing the article.
Knowing several 20+ year service firies – I asked them about this.
All of them said that they will virtually never walk on a roof with a residential fire due to the risk of the roof giving way. About the only activity they do with the roof is to sometimes vent the smoke by making a hole close to the edge.
Apparently too many roofs are of such poor design or maintenance (or both) that walking on them with the extra 20-30kg of air tank/breathing apparatus plus body weight is a risk without a fire.
Add in a fire that can have already weaken say the small timber battens 10-20mm x 20-25mm holding up the terracotta tiles – is not worth the risk. Then there is the age of the tiles, many of which just shatter when stepped on due to their age.
As one firie said, “Nobody wants to drop through the roof, that’s why we have aerial appliances available if necessary.
On commercial structures with steel girders etc holding up the corrugated iron roofing sheets – they rarely walk on those.
None of the firies I spoke with have EVER gone on a roof & turned off the roof top isolators ever.
This article is overstating the issue. I have been installing solar rooftop PV for 10 years. Yes rooftop DC isolators are mostly probably a stupid idea. They are good when maintenance work on a solar array is warranted. As to module level shut-down, that can also be accomplished with DC systems such as Tigo and SolarEdge. These days DC isolators have to be installed with very good weather coverings. And not cool singling out Chinese products as the culprit – ‘you get what you pay for’. Australian standards are strong now with regard to DC isolators.