The slowest wind conditions on record in some places of South Australia have slashed east coast wind generation in the June quarter, pushing up electricity prices, cutting wind farm profits and spurring concerns about future energy market planning.
The trend, spurred by unusually high pressure systems in the Great Australian Bight that are becoming more prevalent as the globe warms, is forecast to continue in July and August, the weather bureau says.
The so-called wind drought has meant National Electricity Market wind generation in the June quarter, the first quarter after this year’s closure of the Hazelwood brown coal-fired power station, was its lowest in five years, despite rapid growth in the number of wind turbines.
It has added pressure to a power market already experiencing widespread retail and industrial price increases because of the closure of Hazelwood and struggling to deal with the growing presence of intermittent wind and solar power.
The drop in wind supply pushed average South Australian prices for the June quarter to $116 per MWh, up from $81 in the previous June quarter.
Last week, New Zealand wind power company Tilt Energy, which owns the Snowtown 1 and Snowtown 2 wind farms in South Australia, issued a $10 million-$12m pre-tax profit downgrade because of the lack of wind.
It followed a $9m-$12m downgrade for the same reason the previous week by Sydney-based Infigen Energy.
“Production from Australian assets for June will represent the lowest month of production since the full commissioning of these assets in 2008 and 2014 respectively,” Tilt said, adding that April and May had also been below expectations.
It said a below-average quarter of this magnitude was expected to occur over every three to four years.
NEM analysts WattClarity says June had the lowest wind speed at Adelaide airport and the city for any month in the past 10 years. WattClarity analyst Paul McArdle said NEM wind power in June was its lowest in five years, despite increased generation capacity.
Mr McArdle said this was “truly astonishing” and demanded attention, given the NEM was becoming heavily dependent on wind power.
“This indicates we, as an industry, need to be far more sophisticated in our approach to planning, business, development and operations than has been the case to date, and that the mechanism that have got us where we are, including the Renewable Energy Target, are not going to be good enough to get us where we need to go,” Mr McArdle said.
The weather bureau said it was the lowest wind at multiple South Australian weather stations for any June since measurements across the day began in 1995.
This included Adelaide airport, where the wind was 39 per cent below average.
Darren Ray, a senior climatologist at the Bureau of Meteorology, said the low winds had been caused by a high pressure system over the Bight.
While this had eased, and wind had picked up, it was expected to return.
“Modelling of weather patterns is keeping the high pressure systems a bit stronger than average, with lower than average winds, over July and August,” he said, adding it was probably not going to be as extreme as June.
Global warming was making the high pressure systems more common.
“There is a long-term trend linking it (high pressure systems in the Bight) to climate change,” Mr Ray said.
“The tropics expand as the planet warms and that sees high pressure systems staying throughout the south longer than they used to.”
Infigen said its June quarter wind output was 40 per cent below the previous June quarter and 30 per cent below its previous June average.
“Infigen had expected its east coast wind farms to benefit from weather patterns that typically result in high wind speeds and solid production in the second of June,” the company said.
“These customary seasonal weather patterns have passed to south of mainland Australia resulting in below average wind conditions.”
Source: The Australian