Interconnector Watch

VIC1-NSW1 (Heywood's northern counterpart, the VIC–NSW interconnector) is the standout story this morning, flowing 785.73 MW from Victoria into NSW and sitting exactly at its export limit — it is binding. That hard ceiling is directly reflected in the price spread: Victoria clears at just $11/MWh while NSW sits at $86.47/MWh, an $75.47/MWh differential that cannot be arbitraged away while the constraint holds. The negative settlement residue notices from 4 April — where the NRM_NSW1_VIC1 constraint was briefly invoked and then cancelled — indicate this corridor has been under sustained pressure, and today's binding condition confirms the export limit continues to cap northward flows. Traders holding NSW–VIC settlement residues should note the accumulation risk flagged in those notices remains a live consideration.

Elsewhere, flows are well within limits and price spreads are more contained. Heywood (V-SA) is exporting 269.24 MW from Victoria into South Australia, at its export limit of 269.24 MW — this is technically at-limit but not flagged as binding in the dispatch solution, and the $34/MWh spread between Victoria ($11) and SA ($45.10) is consistent with this transfer volume. Murraylink (V-S-MNSP1) adds a nominal 9 MW into SA, essentially at its export limit of 9 MW but non-binding. QNI (NSW1-QLD1) is flowing 143.82 MW northbound from NSW into Queensland — a modest volume well within the 756.94 MW export limit — and the near-parity between NSW ($86.47) and QLD ($85.83) explains why there is little dispatch incentive to push harder in either direction. The active constraint notice Q-LCCP_8859, triggered by the unplanned outage of the Larcom Creek–Calliope River 275kV line on 5 April, remains in force and is constraining both QNI and the Terranora DC link (N-Q-MNSP1); Terranora is currently at zero flow, consistent with that constraint set being active on both interconnectors.

Basslink (T-V-MNSP1) is at zero MW in both directions. With Tasmania priced at $96.18/MWh — the highest mainland-connected region — and Victoria at $11/MWh, the absence of southbound flow into Victoria is notable; the import limit is set to zero in this interval, indicating a scheduled or operational restriction is preventing any Tasmanian export across the link right now. Grid engineers should monitor whether that limit relaxes in coming intervals, as the price incentive to flow south is significant. Overall, the binding VIC–NSW constraint is the primary price-shaping mechanism across the NEM this morning, with the Larcom Creek outage a secondary factor capping northern Queensland transfer capability.