Australian Energy Regular will not pursue further claims against wind farms, but AGL agrees to pay fine and court costs

The Energy Regulator will abandon the final case against wind farms over the 2016 blackout. But AGL has still agreed to pay for breaching some rules.

Claims that wind farms caused the statewide blackout will not be pursued by the Australian Energy Regulator.

However, energy company AGL has agreed to be fined $3.5m and pay court costs over breaching electricity rules.

In the fourth and final case against wind farms, the regulator and AGL on Friday presented an agreement to the Federal Court.

AGL admitted it breached rules of the National Electricity Market because it had not had received written approval on voltage protection settings on turbines at four wind farms in the Hallett region.

As a consequence, the Australian Energy Market Operator was compromised in being able to run the electricity system because it was not informed about the ability of the wind farms to ride through fluctuations if an unexpected event occurred.

The site of the damaged power towers near Melrose in the state’s Mid North.

However, AGL did not accept the wind farms tripping off were a “causative link”, Cameron Moore SC, appearing for AGL, told Justice Besanko.

The circumstances of the blackout – where three transmission lines were damaged by a storm – was an “almost unheard of possibility” and an event “unknown throughout the world”.

Appearing for the AER, Ruth Higgins SC said the regulator would not press allegations relating to the wind farms causing the blackout.

The case against AGL follows similar action against Pacific Hydro, Hornsdale and Snowtown farms – which also did not admit being the cause of the blackout despite breaching rules on settings. They were fined $1.1m, $550,000 and $1m respectively.

Dr Higgins said on September 28, 2016, there were four significant voltage fluctuations in the electricity grid within 90 seconds.

The wind farm turbines, which were set to ride through three fluctuations over 120 seconds, shut down to prevent damage to their equipment.

In turn, the Victorian interconnector and gas-fired power stations also tripped off for their own protection.

Mr Moore said AGL had not been aware of the settings which were put in place by turbine supplier Suzlon.

AGL had inadvertently breached a rule that these settings should have been approved by ElectraNet or the Australian Energy Market Operator.

The court heard there was no stated number of ride-throughs in the rules, but turbine settings had been changed to seven.

AGL agreed it should be fined $3.5m, pay $300,000 in court costs and pay for a review and compliance program.

Justice Besanko reserved his decision to a date to be determined.