Micro tips for better solar safety

The recent isolator fires are a handy reminder to solar and electrical companies about the risks in using cheap, imported devices – and the benefit of micro inverters.

Like any other electrical product, solar systems can be dangerous, there is no denying that.

The recent case of yet another safety recall for solar isolators is a sad reflection on the challenges that everyone in our industry faces; whether you are a customer, importer, distributor or installer.

Rooftop DC isolators are required nationally in Australia as a result of very well intentioned evolution of our safety standards. Industry, utilities and fire safety bodies all contributed to the design and implementation of new standards over the last few years that made these devices mandatory with one intention: to make solar safer and reduce risk.

Although the current politically motivated media frenzy is focused on problems, the fact is that the vast majority of solar systems are safer than ever before and an absolutely tiny proportion of the 1.5 million systems installed have had serious problems.

Ironically, despite the best intentions of many, faulty DC isolators are arguably creating more problems than they are solving if press reports are accurate. The fire brigade wanted them installed so arrays could be isolated, de-energising DC cabling. Utilities wanted them so that they could potentially assess from ground level if an array was live or not. Industry wanted them so that we were contributing to safer deployment of solar and nationally consistent standards.

In the case of the recent Queensland case, between 50-70 fires have been reported on solar systems using the affected brand of isolator. Statistically, this represents 0.0001 to 0.0002 per cent of all installed solar systems in Queensland that have been affected although, importantly, total sales may represent as many as 5-10 per cent of total installed systems.

The root cause of this issue lies squarely at the feet of the manufacturers of these devices and the real tragedy is that often well-meaning importers are 100 per cent exposed and offshore manufacturers are immune from the whole issue. Sadly, it has become a salient reminder to solar and electrical companies who buy components that there are huge risks that could send you bankrupt in devices worth less than $20. A longstanding Queensland company has gone under as a result of this debacle and now consumers and installers are left to bear the brunt of recall costs.

Having said all this, the hysteria being whipped up around this has now become a political and media feeding frenzy. Queensland senator Ron Boswell’s attack on the industry in mainstream media accompanied by alarmist headlines is a thinly veiled attack on the industry, nothing more nothing less.

Solar arrays are not immune from risk, but the majority are safe, are not “ticking time bombs” and technological and standards development are constantly improving safety.

I’ll be frank: it’s one of the things that I just love about micro inverters. If mains power isn’t present, micro inverters automatically shut off the output of panels at low voltage (24-45V DC nom). For fire brigades, solar owners and installers, array isolation is as simple as flicking the main AC fuse (in an emergency, it could be cutting power to the street). In such a case, AC voltage is removed from the roof, DC system voltage is reduced to safe levels and the brigade can attack the rook with their axes’ safely, if that’s what they need to do.

Now, I’m not suggesting we should mandate micro inverters but one thing’s is clear, they eliminate the risk of high voltage DC fires and the potential for DC isolator failure. Until their quality is assured and manufacturers are brought to account, I know what I’d be choosing.

Data

Interestingly, safety can also be related to the ease of access to data.

Great data is like a roadmap, it tells you what’s going on, where you have been and, potentially, what’s coming up. If you have a fault condition or emergency, access to good data can potentially help.

Not a day goes by when I don’t consider data in relation to solar. Whether it’s monitoring my own solar system, analysing a client’s system performance or some other aspect, data saves me time and money. It empowers me.

However, you can also drown in data. It needs to be filtered, accurate, manageable and meaningful. Well managed data leads you to powerful insights and outcomes, and that’s where evolution gets exciting (in a geeky kind of way).

Data can describe the increasingly important relationships between consumption and generation, essential for designing financial outcomes. It can be used to drill down into solar generation, to understand what’s happening and, potentially, why – before mobilising a fleet of crews.

With the emergence of PPAs, data can become more than ones and zeroes and can become a financial auditing tool, a billing tool and a proof that you are meeting your contractual obligations. It can help you manage new business models and forecast cash flows, for goodness sakes, based on annuities rather than a cash sale upfront.

If you don’t have great data and powerful insights into what it’s telling you in efficient ways, you’re cactus my friend, compared to those who do.

I nearly abandoned school when they tried to tech me algebra and advanced maths, but now I get it. Data and mathematics can become insights that save time, money and tell stories. And that’s kinda cool.

Nigel Morris is the director of Solar Business Services. 

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