By Terence Lee, FM Global
Victor Hugo once said that all forces in the world are not so powerful as an idea whose time has come. He could have mused that all the forces in the world can’t stop businesses making investments that are profitable.
So it is with solar power in Australia – or so it seems. Despite the current debate around the technology, investment is growing exponentially. This has mostly been attributed to its increasingly obvious financial benefits.
Last year, the Australian Renewable Energy Agency said the cost of building large-scale solar energy generation had fallen to ‘extraordinary new lows’ of about $50 per megawatt-hour (MWh). This looks even more significant when set against the context of rising electricity costs.
In its Integrated System Plan, released in July 2018, the Australian Energy Market Operator (AEMO) shunned coal when forecasting how Australia could best meet its transmission requirements for the next 20 years. It pointed instead to solar and wind.
Queensland is leading the charge, with more than 1300 megawatts of renewable projects worth $2.6 billion. Its 21 solar farms include the APA Group’s Darling Downs Solar Farm with 138 MW and Stage One of Genex’s Kidston Solar Project with 126 MW. Another 13 solar farms are in the pipeline, according to The Australian Financial Review.
So far so good for the companies behind these plants, consumers and the environment. But all is not as it seems.
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Factoring in cyclone risk
What’s been overlooked is that there’s currently no standardised testing procedure to determine whether these solar farms will withstand cyclones. The only testing of Australian solar PV is to European standards. This considers resistance to snow loads, not tropical cyclones. In other words, the true cost of these economically advantageous solar investments hasn’t been factored in.
This is particularly problematic given such storms are hardly a rare occurrence. There have been 47 tropical cyclones in Australia since 2010, bringing gale-force winds, heavy rain and storm surges. Queensland is often in the eye of the storm.
Action is needed to ensure this potential boom doesn’t bust. Risk is reduced by introducing standardised, national testing of solar panel resilience. Fortunately, we’re now closer than we’ve ever been to knowing what that testing might look like.
We recently worked with Sun Metals Corporation near Townsville to test the resilience of its solar farm, the largest behind-the-meter facility in Australia (124 MW). It covers 120 hectares of land with more than a million ground-mounted solar panels connected to its existing 33/132 kV substation.
Within the expected design life of the solar farm, there is a 20 per cent chance of it being hit by a cyclone that would cause significant damage to the solar panels. While some other companies have taken on the risk of installing similar farms, and insurers may have taken on the risk of insuring them, we felt it was imperative to develop a better understanding of whether these fixed-tilt, ground-mounted solar panels could withstand the force of a cyclone.
Over four months in early 2018 we collaborated with James Cook University’s cyclone-testing station to develop an appropriate protocol for the Sun Metals solar farm. The plan was to determine the failure mode of the entire structural system such as, whether the framework would buckle, if the panels would crack and how their electricity output would be affected if the panels were subjected to cyclonic winds.
Using existing wind-tunnel data from the solar farm project and after conducting structural static tests, we subjected the solar panels to hydraulic pressure equivalent to 250 kilometre-per-hour cyclonic winds. We applied this pressure to the panels 10,000 times to simulate the reality of a powerful storm.
The results? The panels cracked at the clamps, but still produced electricity, allowing the issue of the cracked clamps to be addressed before an actual cyclone strikes. This test enabled FM Global to have a clear picture of the potential risk involved.
Because most large-scale solar farm projects are of bespoke design to best utilise the topography of the site and the needs of the owner, each solar farm project may need to undergo testing to determine whether the solar farm can withstand the impact of a cyclone.
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A more resilient industry
The next steps are for this type of testing to become a national standard, and for standardised testing for all types of panels and installation configurations to be implemented. We believe the Queensland Government’s recent announcement that it will restrict the installation and removal of solar panels to licensed electricians is a step in the direction of the recognition for the need for increased regulation to protect investment in renewable energy projects as well as ensuring solar farm installations are safer. But it leaves questions around what guidelines these professionals should be adhering to during the installation process. This is where attention should be turned to next.
New standards and regulations could slow investment in the short term, but in the long run it will make the industry itself more resilient. Without it, all solar stakeholders could be left vulnerable to an embarrassing black eye when the next major cyclone strikes.
The last thing we want is for this increasingly important energy source – and investments worth billions of dollars – to be written off unnecessarily. The time has come for a smarter approach to solar installation. Actions will speak louder than words.