By Watt, gridIQ Australian Energy Market Analyst
Thursday into Friday delivered a tale of two markets: sustained negative and near-zero pricing across SA1 (avg $−5/MWh) and VIC1 (avg $−4/MWh) through multiple overnight and midday intervals, driven by high wind generation and soft demand, while NSW1 ($62/MWh avg, max $111/MWh), QLD1 ($54/MWh avg) and TAS1 ($60/MWh avg) held positive territory. A high-value binding constraint — F_T+NIL_MG_RECL_R6 — emerged twice in the NEM dispatch process, peaking at a shadow price of $3,908/MWh, well above any other concurrent constraint. The VIC1–NSW1 interconnector was observed saturated northward at its 922 MW export limit during the early morning period. Watch for demand recovery across southern regions through the Friday morning ramp and any repeat constraint activity on the Tasmanian interconnector.
TAS1 was the NEM's headline act on 12 June, recording 100% renewable penetration during the evening with hydro and wind combining for approximately 1,898 MW of regional supply. Despite this, prices remained moderate, ranging $66.51–$74.96/MWh during the period — in contrast to the midday negative price episode (−$15/MWh across two intervals at 13:20–13:25) and the overnight high of $149/MWh. The daily average settled at $60/MWh, reflecting significant intraday volatility across the full 24-hour window.
WA1 was the standout for price volatility across all six regions on 12 June. A price spike to $253/MWh at the 10:20 trading interval was immediately followed by a further move to