regional sa — SA1
The SA1 spot price sits at -$4.95/MWh at 18:15 AEST, with demand at 994.88 MW — a Sunday morning low typical of the region. Negative pricing has been persistent through the solar window, with prices bottoming at -$58.69/MWh around midday before recovering into the evening peak, where prices ran $50–$70/MWh between 18:00–22:00 AEST. The overnight period from 10:00 AEST yesterday through to early this morning has been overwhelmingly negative, reflecting rooftop and utility solar saturation overwhelming demand on a low-load weekend day. The current -$4.95/MWh reading confirms solar generation is now ramping as the morning progresses, suppressing grid-level prices despite demand still sitting below 1,000 MW.
The generation mix at 18:00 AEST shows wind carrying 312.78 MW and gas CCGT contributing 80 MW, with solar at zero MW — consistent with pre-dawn conditions at the time of that snapshot. No OCGT is online. With 91% cloud cover and solar potential rated at just 0.3, rooftop solar output will be materially constrained through the morning, limiting the depth of negative pricing compared to yesterday's solar-driven nadir. Wind potential is equally weak at 0.2, with wind speed at only 5.2 km/h, meaning the 312.78 MW wind figure is near current capacity ceiling and unlikely to expand significantly today.
Carbon intensity sits at 0.0566 tCO2/MWh with renewable penetration at 88.46% — a strong reading, though notably down from the 95%+ renewables share recorded overnight on Saturday when wind was dominating a very low demand base. The carbon intensity trajectory through the price history tells the story clearly: intensity peaked at 0.3588 tCO2/MWh during the afternoon when gas was carrying peak load in the $60–$70/MWh window, then compressed back as wind re-established overnight dominance. With gas CCGT still online at 80 MW providing inertia and system strength support, intensity is unlikely to reach the sub-0.025 tCO2/MWh floor seen overnight Saturday.
No market notices are active for SA1. With no predispatch forecast data available, price trajectory today will hinge on cloud cover persistence and wind recovery. The weather profile — high cloud, low wind, no cooling or heating demand — points to a relatively flat, low-demand Sunday profile. Expect prices to remain negative or near-zero through the solar window (09:00–15:00 AEST) if cloud breaks at all, then recover to the $40–$60/MWh range during the evening ramp as gas re-dispatches to meet rising residential demand. Grid stress score of 63 warrants monitoring given the low wind potential and CCGT dependency for system services.