Interconnector Watch: Saturday 20 June 2026

The single binding interconnector right now is QNI (NSW1-QLD1), sitting at -461.68 MW — exactly at its import limit of -461.68 MW, meaning Queensland is drawing maximum allowable flow from NSW and the constraint is fully active. This is the dominant price-shaping dynamic across the NEM at 06:30 AEST. Despite QLD importing at the interconnector ceiling, its price of $82.88/MWh sits $7.20/MWh below NSW at $90.08/MWh — a spread that reflects the binding constraint preventing further arbitrage from closing the gap. Directlink (N-Q-MNSP1) is simultaneously affected by an active AEMO market notice: controls to vary its output have been unavailable since 18:40 AEST yesterday, with constraint set I-CTRL_ISSUE_TE invoked and remaining active. At -33 MW, Directlink is flowing NSW-to-QLD but is effectively locked at its current position until the control issue is resolved.

On the Victoria-centred interconnectors, Heywood (V-SA) is carrying 516.9 MW from VIC to SA against an export limit of 556.72 MW — utilisation at roughly 93% — and while not technically binding, it is operating close to its ceiling. This partially explains SA's $90.58/MWh price sitting above VIC's $80.50/MWh; Heywood is transferring near capacity but cannot fully close the $10.08/MWh spread. Murraylink (V-S-MNSP1) adds a further 54 MW VIC-to-SA, well within its 84.81 MW export limit. Importantly, both V-SA and V-S-MNSP1 remain subject to an active constraint (CA_SYDS_594882A3) triggered by a rating change on the X3 Balranald–Buronga 220 kV line, which continues to limit transfer capacity on those paths. VIC-NSW is carrying 481.35 MW northward from Victoria into NSW, utilising around 41% of its 1,179.56 MW export limit — ample headroom — and the $9.58/MWh VIC-to-NSW price differential is consistent with unconstrained but directional flow.

Basslink (T-V-MNSP1) is at zero flow. Tasmania's $70.24/MWh — the lowest regional price in the NEM — would ordinarily incentivise exports to Victoria at $80.50/MWh, but the ongoing outage of the APD A2 500/220 kV transformer in Victoria (constraint set F-I_ML_APD_LOAD, active since 10 June) continues to limit Basslink's transfer capability, keeping that $10.26/MWh spread unresolved. The long-running Kerang–Koorangie 220 kV line outage (constraint set V-KGKO, active since 9 June) also remains in force, with equations referencing V-S-MNSP1, T-V-MNSP1, V-SA, and VIC1-NSW1 — meaning multiple interconnector limits on the Victorian network are simultaneously shaped by this unplanned outage. The net effect today is that Victoria is acting as the NEM's central dispatch hub, exporting in three directions while subject to compounding network constraints on both its SA-facing and Tasmania-facing paths.