Ergon denies load shedding

A SYSTEM fault led to a lowcost electricity tariff supplying power throughout regional Queensland being inadvertently switched off, distributor and retailer Ergon Energy says.

Ergon was commenting after consumers raised concern about the outage, which lasted for about eight hours on Sunday.

The residential Tariff 33 is an interruptible supply used by consumers to cut the cost of their electricity bills but which is normally available for a minimum of 18 hours each day.

It is commonly used for pool pumps, hot water systems and airconditioners.

On Sunday, consumers complained in Facebook posts about not being able to use their airconditioners at a time when the air was thick with smoke from fires.

Some also questioned whether authorities were load shedding – cutting power to protect system security or mitigate damage to infrastructure.

But a spokeswoman for Ergon said the cutting of Tariff 33 was a system fault and not load shedding.

“For customers connected to Tariff 33 in regional Queensland, a system fault led to the tariff being inadvertently switched off for a number of hours,” an Ergon spokeswoman said.

“Tariff 33 channels were progressively restored throughout the day, with all channels returned to normal by 3.30pm.”

The spokeswoman said technical experts were investigating the cause of the fault, which had not occurred before.

Consumers on Facebook said the failure seemed odd at a time when demand on the system was low.

An independent candidate for the state seat of Hill, Tolga resident Peter Campion, said generation records showed the outputs of the Mount Emerald wind farm and the Sun Metals solar farm in North Queensland had been curtailed this month well below capacity.

Mr Campion said the reason for this was that one of the units of Rockhampton’s Stanwell coal-fired power station was offline and the level of intermittent power needed to be cut to maintain system stability.

A spokeswoman for regulator the Australian Energy Market Operator confirmed the reliance on coal-fired power but not Stanwell’s role.

“In order for inverter-based generation to be able to generate at full capacity in central and North Queensland – wind and solar farms including Sun Metals solar farm – a minimum amount synchronous generation – typically coal, hydro and gas power stations – must be online,” the spokeswoman said.

“The limits for inverterbased generation depend on the specific combination of synchronous generators online at the time.”