The world’s second-most powerful battery could be built in the Top End as part of a plan to produce more renewable energy for the Northern Territory.
Territory Generation, the NT Government-owned corporation that runs power plants in the jurisdiction, wants to build a large-scale renewable energy storage system for Darwin and Katherine.
It has released an expression of interest for a 25 to 45 megawatt battery.
By comparison, the new Tesla battery in South Australia — the world’s largest — is 100 megawatts, said Dr Ariel Liebman, from Monash University’s Energy Materials and Systems Institute.
“‘Until the Tesla battery went in, the largest lithium ion battery in the world was around 30 megawatts, so this would be the second-largest,” Dr Liebman said.
“[It’s] just less than half the size of the Tesla battery in South Australia, but relative to the size of the system it would be going into it’s actually quite large, it’s a very significant piece of kit.
“The system itself is only a couple of hundreds of megawatts or so, so it’s going to have a significant impact if it’s operated in the way that it’s needed.”
As the NT Government moves to a 50 per cent renewable energy target for 2030, the battery would be able to help balance the power system on cloudy days or if another generator tripped, which often happens with thermal generators that burn coal or gas, Dr Liebman said.
“Now that batteries are coming into their own, they’re cheaper than they used to be and they’re actually much faster-responding than thermal generators, so it would add an additional tool to the toolkit of the power system operator,” he said.
He estimated the cost of such a battery to be about $7 million.
Growing number of large-scale solar power systems in NT
In its expression of interest document, Territory Generation is seeking design parameters of 25MW, 35MW, and 45MW power outputs, with an energy storage of 30 minutes — and alternatives of up to an extra hour — at the rated capacity.
Territory Generation anticipates that the number of residences with rooftop solar PV systems in the NT will increase from one in 10 homes in 2015-16 to almost one in three over the next eight years.
It also stated that there are a “growing number” of large-scale solar PV systems connected to the Darwin-Katherine power network, with eight systems that currently have a capacity of more than 100MW.
The battery would need to be able to supply power during periods of large solar PV capacity loss, such as on cloudy days.
Darwin International Airport’s solar plant has a capacity of 5,524kW, and Darwin’s main shopping centre at Casuarina Square has a solar capacity of 1,252.9kW.
In the NT, peak usage is during the wet season from September to April, while the lowest usage is during the dry season, from May until September.
NT Government injected $20m to keep Territory Generation afloat
Just before Christmas, Territory Generation revealed it was broke, and the NT Government injected $20 million into the ailing utilities corporation to keep it running, as it replaced the board and released a heavily-redacted and damning report.
The report revealed at least $43 million in budget blowouts caused by soaring fees, bloated staffing levels, and over-spending on projects.
The NT Government had to approve an unplanned $20 million loan in the last financial year to help fund capital projects, and doubled Territory Generation’s overdraft facility from $10 million to $20 million.
Despite doing this, it will still not be enough to pay costs this year “if corrective action is not taken”, the report said.
While Territory Generation indicated it would push for power price increases from July 1, the Labor NT Government insists that prices will only rise with CPI during its first term, which runs until August 2020.