Around 100,000 WA households were plunged into darkness on Friday night, as a failure caused by a fire at a “baseload” gas-fired power station forced the market operator to cut power to homes to prevent a larger scale blackout across the state.

A turbine fire forced the shutdown of the 320MW NewGen gas-fired power station, owned by NewGen Power and located in Kwinana, which is a joint venture between Energy Infrastructure Trust and the Sumitomo Corporation.

As reported by the ABC, around 30 firefighters attended to the fire at the power station, which is believed to have started within one of the power station’s turbines. The fire caused the immediate loss of supply from the gas-fired generator, which caused the supply-demand balance within the Western Australian power grid to become unstable.

The Australian Energy Market Operator (AEMO) which oversees the operation of the Western Australian power grid, said the failure at the NewGen gas generator had a cascade effect on other parts of the grid, causing the subsequent trip of the 80MW Badgingarra Wind Farm and the 120MW Worsley Alumina Power Station.

The sudden loss of supply triggered an urgent need to shed load from the WA grid, with around 100,000 homes losing power across Perth, Kalgoorlie and Geraldton for around two hours on Friday night. Western Power estimated that around 8 per cent of WA customers were affected by the load shedding event.

Automated systems were triggered by the sudden outage at the NewGen gas generator, which intervened to cut supply to homes to restore balance within the electricity system.

With the loss of generation, the frequency of the WA fell dramatically from its standard operating frequency of 50 hertz. Utility Western Power said that the WA grid frequency fell to 48.75 Hertz, an unsafe level with in the grid, with customers needing to be disconnected to maintain stable supply and prevent further failures across the grid.

“In less than one second the automated systems assessed the entire network load and other real-time data to shed load throughout the network, creating a large number of emergency unplanned outages,” Western Power said in a statement.

“We immediately worked with the Australian Energy Market Operator (AEMO) who dispatched reserve and other online generators to make more generation available for us to return power back to impacted customers.”

Supply was restored to households once additional electricity generation was secured by AEMO, with the initial blackout impacting homes from around 8 pm (AWST) on Friday evening.

“AEMO immediately dispatched additional reserve generation to restore the system frequency back to the safe operating levels, and at 8:27 PM (AWST) AEMO advised Western Power it could begin restoring power to the affected consumers,” AEMO said in a statement.

“Approximately 98,000 consumers were impacted by this supply interruption, and a large majority of users had their power restored within the hour. The final 2,000 consumers were restored by 11:30 PM (AWST).”

Government-owned Western Power, which operates and maintains the state’s network infrastructure said that its control systems effectively managed the outage, and prevented a larger loss of power.

“This type of large generation loss is very rare, and, while impossible to predict, Western Power’s intelligent designs systems are prepared to meet these unusual events almost instantaneously while delivering power safely and effectively,” Western Power said in a statement.

Western Australia operates on a separate electricity system from the rest of Australia, and therefore no homes outside of WA were impacted by the outage.

AEMO will conduct an investigation to identify the “root cause” of the failure at the NewGen power station and subsequent load shedding event.

“[AEMO] has implemented temporary, special operational arrangements to protect the system while the investigation is underway. AEMO will publish the findings of this investigation once it is completed,” AEMO said.