Interconnector Watch: Sunday 28 June 2026

The dominant feature right now is VIC1-NSW1 (Heywood's northern cousin, the VIC–NSW interconnector). It is the only binding interconnector in the NEM at 06:30 AEST, flowing 507.77 MW northward from Victoria into NSW against an export limit of 527.11 MW — utilisation sits at 96.3% of that cap. That binding constraint is directly reflected in the price spread: Victoria clears at $71.09/MWh while NSW sits $9.01/MWh higher at $80.10/MWh. With the interconnector at its limit, additional low-cost Victorian generation cannot arbitrage across the border, sustaining the spread. Traders should note that the NRM_VIC1_NSW1 negative settlement residue constraint was active as recently as 23 June and is flagged as still active in market notices — a signal that the VIC-to-NSW direction has been accumulating residues under sustained northward flows.

On the QNI corridor, NSW1-QLD1 is carrying 921.85 MW southward from Queensland into NSW — 89.8% of its import limit of 1,026.61 MW. This flow is not binding but is substantial, and it is compressing the NSW–QLD spread: Queensland clears at $69.70/MWh against NSW's $80.10/MWh, a $10.40/MWh gap consistent with QLD exporting at volume to meet higher-priced NSW demand. Directlink (N-Q-MNSP1) adds a further 49 MW southward from QLD to NSW. Note that Directlink's output controls remain unavailable per the active market notice from 20 June (constraint set I-CTRL_ISSUE_TE), which constrains the operator's ability to vary that flow — it is locked near its current dispatch level until further notice.

Heywood (V-SA) is flowing 103.81 MW westward into SA at modest utilisation — the export limit sits at -64.35 MW (SA-to-VIC direction), meaning the current westward flow of -103.81 MW is beyond that limit in the import direction and sits well within the import limit of -607.30 MW at just 17.1% utilisation. SA at $67.41/MWh is the cheapest mainland region, consistent with net imports supplementing local supply at low cost. Murraylink (V-S-MNSP1) carries only 9 MW westward into SA and is not binding, but it remains subject to an active constraint (N-BU_7118) tied to the Buronga B Bus 7118 220kV isolator rating change from 23 June, which caps its headroom on the LHS of the constraint equation. The Murraylink outage notice from 22 June (I-MURRAYLINK) also remains active and affects both V-S-MNSP1 and VIC1-NSW1 equations simultaneously — operators should account for that interaction when modelling SA import scenarios today.

Basslink (T-V-MNSP1) sits at zero flow, with Tasmania clearing at $70.20/MWh — virtually flat to Victoria's $71.09/MWh, which removes the price incentive to push power in either direction at this interval. Tasmania's export limit to Victoria is 125 MW and import limit is -46.03 MW, so capacity exists in both directions but the near-zero spread offers no arbitrage signal. The