NEM local temperature alerts

High ambient temperatures reduce the efficiency and the reliability of thermal power stations, wind farms and solar farms, hence their available capacity. The power transfer capability of market network services (MNSP) also reduces at high temperatures. Hence, basing available capacities of plant on forecast local ambient temperatures provides a better representation of supply availability in the NEM.

AEMO has been advising participants via market notices when high temperatures are forecast in NEM regions using a single weather station for each region. AEMO has improved this process by selecting several weather stations (16 weather stations across the NEM) that are close to or have similar weather characteristics to locations where generation clusters are located. A suitable set of alert levels called NEM Local Temperature Alert Levels have been determined for these weather stations.^[1]

Participant communication

When forecast temperatures for these weather stations are equal to or greater than the NEM Local Temperature Alert Levels, AEMO will publish a market notice reminding Generators and/or the MNSP to review the available capacities in their dispatch offers or availability submissions consistent with the forecast temperatures.

Selected weather stations and their Local Temperature Alert Levels are listed in Table 1.

NEM Local Temperature Alert Levels

The market notice includes the following information:

• Period and the Region/s where Local Temperature Alert Levels are reached or exceeded
• Weather station
• Forecast temperature
• Request participants for a review of the weather forecast in the local area where their generating plant are located and if required, update their available capacities consistent with the forecast temperature.

[1] This has reference to AEMO power system operating procedure SO_OP_3703 – Short Term Reserve Management.