SWIS Observatory

Stress days make the transition legible.

The operating days where rooftop solar, minimum demand and the evening ramp expose what an isolated grid must still hold together.

Record: 90 operating days
Lens: Demand, solar and ramp
Source: AEMO WEM

Lowest operational demand

The registered-generation floor, before rooftop solar is added back.

013 Oct 2026890 MW
0213 Oct 2026937 MW
0312 Oct 2026967 MW
044 Oct 2026974 MW
052 Oct 2026982 MW

Highest rooftop PV share

Reading the record

A stress day is a system question, not a score.

A low registered-demand day can still carry high underlying demand once rooftop PV is restored. A steep ramp is not automatically a failure. The point is to see which resources stayed online and what operating capability the system was using.

Open daily record

Behind-the-meter solar as a share of the underlying-demand proxy at its daily peak.

013 Oct 202666.8 %
022 Oct 202666.8 %
0312 Oct 202666.1 %
044 Oct 202665.5 %
059 Sept 202664.9 %

Steepest evening ramp

The rise from the daily operational-demand minimum to the evening operating peak.

0116 Sept 20261742 MW
029 Aug 20261697 MW
0328 July 20261685 MW
041 Sept 20261677 MW
0529 July 20261656 MW