Changes in diurnal wind generation during heatwave events

Australia’s National Electricity Market (NEM) is in a period of transition. Decarbonization pressures, regulatory incentives, and consumer preferences are driving up the share of renewable generation in the NEM. Concurrently, the nation faces pressure to adapt to a changing climate and the extreme weather that entails. As renewable penetration increases variability of electricity supply, climate change reduces the predictability of the weather that fuels renewables. Extreme weather events are changing; heatwaves are getting more severe, more frequent, and lasting longer.  While the physical processes caused by heat on generation technologies are well defined, quantifying and predicting the systemic impacts of extreme events is an ongoing line of inquiry. Modern electricity markets are relatively young and have evolved rapidly. Generally, market datasets are short in duration, poorly standardised, and have limited coverage relative to meteorological data. They are rarely publicly available, as data publication could be considered a risk to the interests of market participants. This presentation utilises Australia’s National Electricity Market’s (NEM) Market Management System Data Model, alongside the BARRA-R2 regional climate reanalysis, to analyse historical changes in the diurnal generation profiles of wind energy during heatwaves. By bootstrapping composite generation profiles of heatwave and baseline summer days, we present how heatwaves impact generation profiles. We then compare how these profiles vary through time and space. Impact curves (bootstrapped difference curves of heatwave and baseline generation) are calculated and used to analyse patterns of heatwave impact across the NEM using principal component analysis and timeseries clustering. Investigating the scales and patterns of heatwave impacts reveal the weather-scale drivers of generation variability. This allows us to identify how large-scale synoptic systems (such as heatwaves) have myriad localised impacts. We then discuss how these localised variations may contribute to larger shifts in generation dispatch and grid stability on heatwave days. This exploratory data analysis leverages a recent, unexplored dataset to develop methods that quantify the impact of heatwaves on wind generation. The primary contribution of this research is methodological; it also offers exploratory empirical findings, highlighting areas for further research.