South Australia (SA1) experienced very high renewable penetration of 96.8%, driven predominantly by wind generation of 1,943 MW, with minimal thermal generation from gas plants. Regional spot prices declined sharply from 17.4 $/MWh to 7.91 $/MWh over the 25-minute period, reflecting the abundant renewable supply.
The high renewable output and low prices were primarily driven by strong wind generation representing over 96% of the generation mix. The binding constraints with the highest marginal values—particularly the constraint with marginal value 27.41 $/MWh and the two constraints with marginal values 4.99 and 3.44 $/MWh—indicate that network or operational limits were restricting further dispatch and preventing prices from falling further, suggesting transmission or system strength constraints were active in managing the high renewable penetration.
Causal analysis generated by gridIQ's synthesis model from live AEMO market data: dispatch prices, generation mix, interconnector flows and market notices in the interval surrounding the event.