Wind resources of southeast Australia during peak electricity demand days

Abstract. Peaks in electricity demand are critical times when it is important to understand the contribution of wind energy to the supply of electricity. In southeast Australia, peaks in electricity demand may be caused by unusually hot or cold periods that correspond to increased cooling and heating loads, respectively. These peaks in demand tend to be centred in the morning and early-evening hours as a result of consumption patterns and behind-the-meter solar generation during the middle of the day. In this study, we examine the characteristics of the southeast Australian wind energy resource on days when the electricity demand is above the 80th percentile for heating and cooling days, respectively. We use a 29-year dataset of reanalysis over Australia. To correct for changes to the electricity system and consumption patterns in this period, a random forest model is fitted that relates the meteorological conditions to the electricity demand during a recent 4-year period. We find positive wind generation capacity factors over many offshore parts of the region during both high-demand hot days and high-demand cold days. Over land, areas of complex topography show positive capacity factor anomalies on high-demand cold days, while other areas show negative capacity factor anomalies. Reverse patterns are found on high-demand hot days. It is shown that high-demand hot days are associated with a blocking high in the Tasman Sea, while high-demand cold days can be split into cold, wet, and windy outbreaks and high-pressure systems associated with light winds. On high-demand hot days, the peak in the diurnal cycle of wind in the offshore declared development area in southeast Australia is aligned with the peak in electricity demand, while high-demand cold days show little systematic diurnal variability.