Interconnector Watch: Friday 29 May 2026

Across the NEM at 06:30 AEST, the dominant flow is Victoria pushing 929.96 MW north into NSW via VIC1-NSW1 (Loy Yang–Bannaby corridor), and this interconnector is binding at its export limit. That constraint is directly reflected in the $27.79/MWh price spread between Victoria ($10.72/MWh) and NSW ($38.51/MWh) — VIC has surplus generation it cannot fully export, keeping its price suppressed, while NSW prices sit materially higher due to constrained import capacity. The Koorangie–Wemen 220 kV line outage (constraint set V-KOWE, active since 25 May) is contributing to the binding condition on VIC1-NSW1 and is also limiting flows on T-V-MNSP1, V-SA, and V-S-MNSP1 simultaneously.

Basslink (T-V-MNSP1) is running at full capacity in both directions, binding at -144.07 MW — Tasmania is importing from Victoria at its limit. This aligns with TAS sitting at $90.94/MWh against Victoria's $10.72/MWh, a $80.22/MWh spread that reflects Basslink's inability to deliver any additional low-price Victorian energy into the island state. The active Murraylink dynamic rating constraint (VSML_RAT_LIM_DYN and SVML_RAT_LIM_DYN, enabled 27 May) is influencing Murraylink (V-S-MNSP1), which is flowing -133.75 MW from Victoria into SA at 89.2% of its current export limit of -150 MW — not binding but close. SA at $18.86/MWh sits below NSW and QLD, consistent with Victorian supply reaching SA with limited resistance at present.

QLD is the highest-priced mainland region at $92.56/MWh, yet QNI (NSW1-QLD1) is flowing only -48.86 MW southward from QLD into NSW — at its binding export limit of -48.86 MW. This means QLD cannot push any more energy south despite the substantial $54.05/MWh premium over NSW, and NSW cannot export north to relieve QLD either given the flow direction. The Northern Interconnector (N-Q-MNSP1) between SA and QLD registers zero flow, with its export limit also sitting at zero, so it provides no relief to QLD today. The Tailem Bend 275 kV East Bus outage (constraint set S-TB275_E_BUS, active since 24 May) remains active and continues to limit V-SA (Heywood), which is currently flowing at just -42.61 MW of a possible -235.56 MW import limit — well below capacity — meaning SA is not drawing heavily on Victoria via Heywood despite the price differential, likely a consequence of that constraint's ongoing impact on available transfer limits.

In summary, two binding interconnectors — VIC1-NSW1 at its export ceiling and Basslink at full import capacity into Tasmania — are the primary drivers of today's regional price divergence. The $82.22/MWh spread between Victoria and Queensland and the $80.22/MWh TAS-VIC gap are both hard against physical limits, with no short-term relief available absent constraint resolution or network restoration.