Interconnector Watch — Monday 4 May 2026

Interconnector conditions at 06:35 AEST are shaped by two binding links and a pair of active network constraints that are directly influencing regional price spreads. The Heywood interconnector (V-SA) is at full export capacity, flowing 508 MW from Victoria into South Australia against an export limit of 508 MW — it is binding. Murraylink (V-S-MNSP1) is simultaneously binding at 162 MW into SA, against an export limit of 163.9 MW. Together these two links are delivering close to their combined maximum into SA, yet SA still clears at $103.44/MWh — a $33/MWh premium to Victoria ($70.15/MWh) — indicating SA demand is not fully satisfied by available import capacity at current Victorian prices. The VIC-NSW interconnector (VIC1-NSW1) carries 416 MW northward into NSW at 66% of its 626 MW export limit and is not binding; this flow is consistent with Victoria clearing $7.59/MWh below NSW ($77.74/MWh). QNI (NSW1-QLD1) moves 215 MW northward into Queensland at 46% of its 463 MW export limit and is also non-binding, a modest spread reflecting the $4.75/MWh gap between NSW and QLD ($82.49/MWh).

Basslink (T-V-MNSP1) sits at zero flow. Two active constraint notices relating to the Sheffield–George Town 220 kV lines in Tasmania remain on the market notices register — a lightning-related reclassification to credible contingency was invoked and subsequently cancelled overnight, with the cancellation notice still listed as active. The net effect is that Basslink is currently unconstrained by the T-GTSH_N-2 set, but zero flow means Tasmania's $88.18/MWh price is disconnected from Victoria's lower $70.15/MWh. Traders should note the cancellation was issued at 00:04 AEST this morning; if conditions deteriorate and the constraint is re-invoked, Basslink export capacity would again be capped, reinforcing the TAS-VIC spread.

Directlink (N-Q-MNSP1) carries only 25 MW southbound into NSW against an export limit of 89.3 MW and is not binding, but an unplanned outage of Directlink's No. 3 leg is active, with constraint set N-MBTE_1 invoked at 02:30 AEST this morning. This has reduced the interconnector's effective transfer capability and is limiting the NSW1-QLD1 flow dynamic on the northern boundary. The legacy QNI export limit restriction (I-QN_550, related to the Armidale–Sapphire 330 kV outage) remains listed as active despite its scheduled return date of 2 May having passed — traders should verify with AEMO's NOS whether this constraint is still binding or has been superseded, as it formally caps northward QNI flows and may be masking available capacity on that corridor.

The dominant price story today is the SA premium driven by both Heywood and Murraylink binding simultaneously on export. With no headroom remaining on either Victorian-to-SA link, any uplift in SA demand or loss of local generation will not be absorbed by additional imports — SA price exposure to the upside is elevated for the remainder of the day. The VIC-NSW corridor has meaningful headroom (210