Australia’s Solar Generation Set to Endure Severe Disruptions Caused by Cyclone Alfred

According to the analysis conducted via the Solcast API and the forecasts released on Friday morning, the photovoltaic power generation in eastern Australia is on the verge of encountering substantial disruptions as tropical Cyclone Alfred approaches its landfall in the southeast region of Queensland. The cyclone's predicted path is anticipated to bring about extensive cloud cover and heavy rainfall to the crucial solar power-producing regions, particularly in southeast Queensland and the coastal areas of New South Wales (NSW). The brunt of the impact on solar energy generation will be felt in the vicinity of the cyclone's core. Conversely, areas that are farther away might actually benefit from increased solar irradiance, thanks to the stabilizing atmospheric conditions on the periphery of the cyclone. Nevertheless, the inherently unpredictable nature of tropical cyclones implies that the forecasts and the potential impacts can shift as the situation evolves.

As of the moment of writing, tropical Cyclone Alfred, which is currently classified as a category 2 system, is forecasted to make landfall between Double Island Point and Noosa, located just south of Brisbane's central business district, on Saturday morning. As it moves further inland, the cyclone is expected to lose some of its strength but will continue to bring about significant cloud cover and rainfall across southeast Queensland and the coastal regions of NSW in the upcoming days. With the storm advancing inland, the irradiance levels are projected to be 30% to 50% lower than the long-term average for the period spanning from March 7th to 12th. In the areas most severely affected, the mean daily irradiance is expected to drop below 2.5 kWh during this five-day period.

The diminished irradiance resulting from this storm will lead to a decrease in photovoltaic (PV) power production across the most densely populated areas of the country. For example, the aggregated behind-the-meter power for Energex, the electricity distributor serving the greater Brisbane area, is forecasted to be 46% lower than the average over the next five days. Moreover, the potential damage to solar energy assets and power infrastructure caused by strong winds and flooding could have an impact on power production in the short to medium term. On a more comprehensive scale, the total aggregated solar power generation for Queensland and NSW is expected to be roughly 30% lower than the average for this time of the year. This is especially significant considering the large proportion of PV generation capacity within the affected regions. Sydney is also likely to be affected by the cloud cover associated with the cyclone after its landfall, with the behind-the-meter power production expected to be 33% below the average.

In sharp contrast, certain areas that are farther from the path of Cyclone Alfred are predicted to experience favorable conditions for PV power production. Parts of southeast Australia may witness irradiance levels that are more than 10% higher than the average from March 7th to 12th. Notably, some regions in Victoria and Tasmania could see irradiance levels that are 20% above the average, and the PV power generation in Victoria is projected to be 14% higher than the average. This phenomenon occurs because a tropical cyclone lifts a substantial amount of air into the upper atmosphere within the clouds at its core. This air then descends outside the cyclone, which suppresses cloud formation and boosts the solar irradiance around the cyclone system.

It is crucial to bear in mind that forecasting tropical cyclones comes with a high degree of uncertainty due to the intricate interactions within these weather systems. Despite the progress made in weather prediction technology, there is still a wide range of possible outcomes, and the forecasts are subject to change. For instance, the ensemble forecasts from the European Centre for Medium-Range Weather Forecasts (ECMWF) present a variety of scenarios for the coming week, ranging from tracks that curve back into the Tasman Sea to paths that extend into the interior of Australia. This variability emphasizes the importance for individuals and organizations in the areas at risk to keep themselves updated with the latest weather information and follow the advice provided by the local emergency services. While the impacts of irradiance at specific locations are highly uncertain, the forecasts that are aggregated over larger areas, such as entire states, are less affected by the exact locations of cloud cover, thus offering a more reliable prediction for the overall PV power production.