Commodity Demand — SA1: Saturday 16 May 2026

South Australia is sitting at 1,226 MW and $168.88/MWh at 6:00 AEST, a price that reflects a structurally tighter supply picture rather than elevated demand. Today's demand trajectory tells the real story: the overnight trough bottomed at around 827 MW near 3:10 AEST before climbing steadily through the morning ramp. The day's peak demand of 1,628 MW landed at approximately 8:20 AEST at $138.04/MWh — notably, the highest prices of the day are not coinciding with peak demand. The most elevated prices, including spikes to $175.97–$189.17/MWh, occurred in the 1,240–1,390 MW range during the afternoon and evening periods, pointing to a supply-side constraint rather than a demand-driven squeeze.

The key structural factor driving this price behaviour is the unplanned outage of Murraylink, confirmed active under constraint set I-ML_ZERO. With the SA–Victoria interconnector zeroed out, SA is effectively islanded from Victorian imports, meaning local gas generation is carrying the load that interconnector flows would normally supplement. At 6:00 AEST, gas OCGT contributes 401.79 MW and gas CCGT 230.72 MW — together accounting for roughly 74% of local generation — while wind sits at 209.07 MW (25.25% renewables). With Murraylink offline, the marginal price is set entirely by SA's own gas plant stack, which explains why prices remain elevated even at moderate demand levels well below today's peak.

Forecast pricing for the remainder of today points to a gradual easing from current levels. The 7:00 AEST half-hour (21:00 UTC) is forecast at $138/MWh, stepping down toward $115–$125/MWh for the 07:30–08:30 AEST window, before lifting again into the $140–$152/MWh range through the 10:00–11:30 AEST period as demand builds toward the morning commercial peak. Sunday demand will likely remain below weekday peaks — today's forecast daily maximum sits around 1,600 MW — but with Murraylink still constrained under I-ML_ZERO, price floors will remain sticky around the $138/MWh gas marginal cost band regardless of where demand lands. Demand-side managers with interruptible loads should note that the overnight window between roughly 11:30 AEST and 03:30 AEST remains the structural low-price opportunity, where forecast RRPs drop into the $60–$103/MWh range as demand retreats and wind output has more influence on price setting.