Tasmania powers up again
The BassLink undersea cable that enables electricity to be traded across Bass Strait was returned to service on 12 June, ending Tasmania’s prolonged and expensive energy crisis.
Energy exports began immediately at 100 megawatt/hours or about one-fifth of the cable’s capacity, utilising generation from full or spilling dams.
An outage of the cable in late December, followed by record low rainfall in the following months, had precipitated the crisis.
Hydro Tasmania saw its total storage fall to a low of 12.8 per cent in April as it was forced to draw on water for generation because of the unavailability of imported energy.
The State-owned energy business now expects to record a loss of $90 million for the year after spending between $140 and $180 million on a multi-faceted response to the crisis.
Following the outage, major industries took a Team Tasmania approach, cutting production in order to reduce energy consumption.
With water resources at an all-time low, diesel generators had to be hired to head off a shortage of power for small business and domestic use.
Hydro Tasmania had spent about $50.5 million on installation and lease costs and about $8.5 million on operating the temporary generators by the start of June.
On 8 June, BassLink announced the third and final joint of the cable repair had been completed and successfully tested.
The 100-strong BassLink team then conducted land-based tests on both the electricity inter-connector and its accompanying fibre-optic communications cable, as well as all associated equipment on either side of Bass Strait.
The cables were then reburied in the seabed and fibre-optic transmission resumed on 10 June, two days before the resumption of power transmissions.
BassLink’s Chief Executive, Malcolm Eccles, said weather conditions had allowed the final part of the jointing work to be completed with minimal interruption.
Mr Eccles thanked his repair team, along with contractors who had helped in the fault-finding and repair efforts over nearly six months.
Investigations continue into the cause of the fault.
Hydro Tasmania began demobilising its temporary diesel generators in the first week of June, starting with the Catagunya and Meadowbank power stations and the George Town and Port Latta sub-stations.
This demobilisation delivered a $2 million saving on lease costs.
The Minister for Energy, Matthew Groom, said: “With storages now at 26 per cent and the major industrials returning to full load, Hydro Tasmania has advised the Government that it continues to be in a position to meet Tasmania’s electricity needs with a reduced reliance on supplementary generation.”
Approximately 135 MW of diesel generation remained available at Que River and Bell Bay.
“Hydro Tasmania will continue to monitor the situation and further judgments will be made about the balance of the diesel generation in the coming weeks,” Mr Groom said.
“I would like to take this opportunity to again thank all people across the energy businesses, Government and BassLink for the tireless effort, to date, to ensure energy security in Tasmania is maintained and the Tasmanian economy and jobs have been protected.”
Hydro Tasmania’s CEO, Steve Davy, said storages would now be re-built, with a focus on Lake Gordon, Great Lake and Lake Echo.
“The remainder of the storages are very full, many are spilling, which means these power stations need to run around the clock to create room to capture more winter rain,” Mr Davy said.
“With all of these generators running – and up to 300 megawatt hours of wind generation available – there is more than enough energy to meet all Tasmanian demand.
“This surplus … will exist for at least the next week without any more rain.
“As a result, Basslink will be used to export to the rest of the National Electricity Market.”
Exports were interrupted briefly in late June by an outage caused by a failure of plant in Victoria.
Hydro Tasmania’s storage levels were at 29.7 per cent on 4 July.
Footnote: During election campaigning, the coalition leader, Malcolm Turnbull, said a second Bass Strait cable was vital for Tasmania. “We have a lot of funds in the Clean Energy Finance Corporation to back investments infrastructure which supports renewable and clean energy,” Mr Turnbull said. “It too will not only provide energy security for Tasmania but it will drive more investment in renewable energy,” Mr Turnbull said. A second inter-connector has been estimated to cost $1.5 billion.
Image courtesy of the ABC
5 July 2016, Tasmania’s Stories Edition 173