Commodity Demand — NSW1: Monday 18 May 2026

NSW spot price sits at $98.14/MWh with demand at 7,815 MW as of 06:30 AEST — well below the overnight peak of approximately 8,955 MW reached around 10:15 AEST yesterday and tracking upward from the mid-afternoon trough of around 6,588 MW at 03:25 AEST. The demand-price relationship across today's data is distinct: when demand was running above 8,500 MW overnight, spot prices consistently cleared in the $240–$340/MWh range, while the afternoon demand trough between roughly 6,600–6,900 MW produced prices in the $84–$98/MWh band. The current 7,815 MW level sits in a transitional zone where pricing remains anchored near the $98/MWh floor, consistent with the marginal cost stack at this load level.

The evening ramp is now underway. Demand has risen approximately 1,200 MW from its daily trough and price has responded modestly, climbing from lows near $84–$88/MWh recorded around 05:40–05:50 AEST to the current $98–$111/MWh range. Forecasts for the 07:00 AEST half-hour interval are priced at $110–$111/MWh, signalling the market expects a continued but measured demand build rather than any sharp spike. The most recent AEMO forecasts for the 21:00–21:30 AEST windows point to $110–$120/MWh, which implies the market is not pricing in a repeat of the $280–$340/MWh conditions seen when demand last cleared 8,800 MW.

One demand-side factor worth monitoring is the Upper Tumut hydro units (Units 1–4), which tripped as a non-credible contingency event at 23:17 AEST on 17 May and were returned to service at 13:27 AEST. That event coincided with the overnight period when NSW prices were running above $280/MWh with demand between 8,700–8,960 MW — the loss of dispatchable hydro capacity tightened the supply stack at an already elevated demand level. With those units confirmed back in service, tonight's demand build faces a more complete supply stack than was available during last night's elevated price period.

The weather outlook for today shows a maximum of 19.4°C with 75% average cloud cover, which constrains solar contribution and sustains heating demand. The current 2.4 heating degree of demand alongside 77% cloud cover means the evening peak demand tonight is likely to follow a similar profile to last night, with demand potentially reaching 8,500–9,000 MW by around 10:00–11:00 AEST. At that load level, and with the Upper Tumut units now available, the pricing corridor is expected to remain in the $110–$180/MWh range rather than the $280–$340/MWh outcomes seen overnight — assuming no further unplanned generation losses. Flexibility buyers and demand-response operators have a short window before the ramp steepens.