Interconnector Watch: Friday 15 May 2026

At 07:35 AEST, the sole binding interconnector across the NEM is Murraylink (V-S-MNSP1), flowing 164 MW from Victoria into South Australia and sitting exactly at its export limit of 164.35 MW. That constraint is directly relevant to the SA1 price, which at $138/MWh is the highest on the mainland and sits $138.10 above Victoria's near-zero price of -$0.10/MWh. Murraylink is fully utilised in the SA direction and cannot carry additional Victorian surplus westward, leaving SA exposed to local supply conditions. Heywood (V-SA) is adding a further 33.6 MW into SA at its export limit of 33.59 MW — effectively also at ceiling — though it is not flagged as binding in dispatch. Combined, these two links are pushing just under 198 MW into a 1,266 MW SA market, yet the price spread confirms that westward transfer capacity is exhausted.

VIC-NSW (VIC1-NSW1) is flowing 359 MW northward from Victoria into NSW at its export limit of 359.15 MW, also effectively at ceiling, though not flagged binding. Victoria's -$0.10/MWh price against NSW's $81.12/MWh illustrates the arbitrage pressure driving that flow to its limit. QNI (NSW1-QLD1) carries a modest 34.9 MW from NSW into Queensland against an export limit of 135.23 MW, leaving around 100 MW of headroom; the NSW-QLD spread of $1.38/MWh is tight, consistent with the light utilisation. Basslink (T-V-MNSP1) is flowing 15.75 MW from Victoria into Tasmania — at its import limit of -15.75 MW — meaning Tasmania is receiving the maximum permitted flow from Victoria. With TAS1 at $104.51/MWh and VIC1 at -$0.10/MWh, the $104.61/MWh spread signals that Basslink's constrained capacity is the binding factor isolating Tasmanian prices from Victoria's current surplus. DirectLink (N-Q-MNSP1) carries just 9 MW northward into Queensland, well within its 78.9 MW export limit; a notice from 5 May remains active confirming that the No. 3 leg of Directlink is on unplanned outage, constraining the link's total capability via the N-MBTE_1 constraint set and the N-AR_TX set from the Armidale transformer outage on 8 May, both of which place equations on N-Q-MNSP1.

The active Victorian constraint notice is also worth noting: VicGrid updated the maximum generation contingency size in south-west Victoria from 600 MW to 750 MW on 13 May, implemented by AEMO in production. This relaxes the upper generation limits applicable during outage conditions in that area, which has relevance for how much Victorian surplus can be dispatched — and therefore how aggressively Victoria can export toward NSW and SA under contingency scenarios. The broader picture today is a Victoria awash with surplus at near-zero prices, with all available export paths running at or near their limits toward NSW, SA, and Tasmania, producing sharp price differentials at each border that reflect constrained transfer capacity rather than unconstrained arbitrage.