Interconnector Watch: Monday 22 June 2026

At 06:30 AEST, two interconnectors are binding and together they are the dominant force shaping today's NEM price landscape. Heywood (V-SA) is at its export limit of 479 MW, carrying power from Victoria into South Australia at full capacity — this hard constraint is directly reflected in SA's price of $230/MWh sitting $82.64/MWh above Victoria's $147.36/MWh. With no additional import headroom available into SA and demand sitting at 1,698 MW, the region is price-isolated at the margin. QNI (NSW1-QLD1) is simultaneously binding on the northward flow at 504 MW into Queensland, pinning QLD's price at $121.11/MWh — $12.30/MWh below NSW's $133.41/MWh — consistent with constrained export capacity preventing further Queensland price convergence with the south.

VIC-NSW is carrying 351 MW southbound from NSW into Victoria, sitting at its import limit of 351 MW and therefore also effectively binding in that direction, which helps explain why Victoria prices ($147.36/MWh) remain elevated above NSW ($133.41/MWh) despite the flow. Basslink (T-V-MNSP1) is exporting 119 MW from Tasmania into Victoria, near its import limit of 119 MW, with Tasmania's $70.20/MWh price — the lowest in the NEM — reflecting ample Tasmanian generation relative to what the interconnector can physically shift northbound. Directlink (N-Q-MNSP1) is carrying 33 MW southbound from QLD into NSW, well within its 132 MW import limit, but remains subject to the active I-CTRL_ISSUE_TE constraint set following loss of control availability notified on 20 June — its dispatch is effectively locked and cannot be varied until that fault is resolved.

Murraylink (V-S-MNSP1) is carrying just 4 MW from SA into Victoria, and is non-binding, but is operating under two active constraint notices. The planned outage constraint set I-MURRAYLINK invoked at 12:30 yesterday has curtailed the link's normal capacity, and the active S-TPRS constraint set — stemming from the 21 June outage of the Roseworthy–Templers 132 kV line — continues to limit transfer into SA across both V-SA and V-S-MNSP1. The combination of these SA network constraints is the structural reason Heywood is binding at its reduced export limit and SA's price premium is as wide as it is today. Additionally, the NRM_SA1_VIC1 negative settlement residue constraint, which fired multiple times during yesterday morning's trading session before being cancelled at 07:50, remains listed as active in the market notices — traders should monitor whether residue accumulation resumes on the SA-to-VIC direction given the ongoing Murraylink and Roseworthy–Templers outages continue to squeeze import capacity into SA.