Interconnector Watch

Across the NEM at 06:30 AEST, interconnector flows are moderate and no link is currently binding against its limit. The most significant flow is on QNI (NSW1-QLD1), which is carrying 534.77 MW northward from NSW into QLD — roughly 53% of its 1,012.81 MW import limit in that direction — consistent with QLD's $64.83/MWh price sitting $6.47 below NSW's $71.30/MWh. VIC-NSW (VIC1-NSW1) is exporting 423.63 MW from Victoria into NSW, utilising 55% of its 771.67 MW export capacity; with Victoria at $64.29/MWh against NSW's $71.30/MWh, the $7.01 spread is drawing supply northward. Heywood (V-SA) is pushing 339.2 MW from Victoria into South Australia — 66% of its 512.46 MW export limit — with SA at $68.84/MWh sitting above Victoria's $64.29/MWh, a $4.55 spread that is pulling Victorian generation across. Murraylink (V-S-MNSP1) adds a further 36 MW in the same VIC-to-SA direction, at 31% of its 115 MW export capacity. Basslink (T-V-MNSP1) is at zero flow, with Tasmania standing alone at $96.79/MWh — the highest price in the NEM — despite having headroom of 125 MW in either direction; the absence of any southward Tasmanian export is notable given the price premium.

Two constraint-related market notices are active and relevant to today's trading. An unplanned outage of the Larcom Creek–Calliope River 8859 275kV line in Queensland occurred at 02:32 AEST this morning, invoking constraint set Q-LCCP_8859 at 02:40 AEST. This constraint has equations bearing on both NSW1-QLD1 and N-Q-MNSP1, meaning the northward flow on QNI may face tighter transfer limits than the raw import limit of 1,012.81 MW suggests — traders should not assume full QNI capacity is available into QLD today until the outage is resolved. Directlink (N-Q-MNSP1) is currently carrying 33 MW southward from QLD into NSW, at 32% of its 104.6 MW import limit in that direction, and is also named in the active constraint set.

The negative settlement residue constraint NRM_NSW1_VIC1 on the VIC-to-NSW directional flow was invoked yesterday afternoon and officially ceased at 15:00 AEST yesterday, but the market notice remains active in the system. The prior accumulation of negative residues on that direction reflects periods where VIC prices exceeded NSW prices while flow was still moving south-to-north — an outcome that can arise from network constraints or dispatch sequencing. With VIC now $7.01 below NSW and 423.63 MW flowing north, residue accumulation risk on that direction is low under current conditions, but participants holding settlement residue auction contracts on VIC1-NSW1 should monitor for any recurrence if the price relationship inverts intraday.

Tasmania's price isolation at $96.79/MWh with Basslink sitting idle is the standout anomaly this morning. With 965.78