The Western Australian government has announced that two of four operating units at Synergy’s Muja Power Station will be retired from October 2022, a move which it says will protect against higher power bills for households and ensure the state’s electricity supply remains stable.

According to WA premier Mark McGowan, keeping the two units operating at Muja C beyond these dates would cost Western Australian taxpayers in excess of an additional $350 million.

“It no longer makes sense to keep the Muja C units operational. They are expensive to run, and demand for electricity from the units is declining dramaticall,” McGowan said.

“Keeping them open will lead to higher power bills for Western Australians and put our stable electricity supply at risk.”

The two Muja D units, Collie Power Station and Bluewaters will continue to operate. The retirement of Muja C will ensure Muja D units operate more frequently, increasing their stability and long term viability.

Increasing levels of residential rooftop solar power has reduced the demand for traditional coal-fired baseload power generation in the South West Interconnected System.

Synergy’s Muja Power Station is the oldest power station in WA, and the generation output for units 5 and 6 within Muja C continues to decline they are only being used around 35 per cent of the time.

The reduced demand means the 40 year-old units are not being deployed as designed. Closing the two C units will allow the two D units to work more often, more efficiently and more cost-effectively.

The high operating costs of Muja C, plus increased maintenance requirements due to the additional cycling of the plant, will force power prices up if it remains open.

It is expected around 30 workers will be affected by the closure of the first Muja C Unit 5 on October 1, 2022. The closure of this unit is expected to have minimal impact on coal production.

A further 40-50 workers will be potentially impacted by the Muja C Unit 6 closing on October 1, 2024.