The results of a public tender for 5MW and up to one hour of battery storage to help lower the use of gas fired generation and integrate a higher level of solar power in Alice Springs is expected to be announced soon.
The tender, the largest of its type in Australia before being overshadowed by larger tenders in South Australia and Victoria in recent months, was launched last October with the short-listed candidates invited to submit final bids earlier this year.
The battery storage is needed to help integrate the high penetration of solar PV in Alice Springs, and reduce the amount of “spinning reserve” in the town’s gas generators.
The Alice Springs network features the 4.1MW Uterne solar power project, and an estimated 7.4MW of distributed solar PV. Its average load is around 25MW, its peak load can hit 55MW, but its minimum can drop to 13MW.
The geographical dispersion of the distributed PV has the effect of dampening sudden step changes in its generation due to cloud cover. The output from Uterne however can fluctuate rapidly under conditions of highly intermittent cloud cover
The state-owned Territory Generation says it has experienced a number of issues with the highly variable load profile from the town, and the impact of cloud cover on solar output and then on the thermal plant.
“The geographical dispersion of the distributed PV has the effect of dampening sudden step changes in its generation due to cloud cover,” it says.
“The output from Uterne however can fluctuate rapidly under conditions of highly intermittent cloud cover.
“Relatively large amounts of thermal spinning reserve is required to counter the solar intermittency and to provide backup for other contingency events which is inefficient, consumes fossil fuels and is expensive.
It said battery storage was essential to support even greater amounts of solar PV penetration, and it could help defer network upgrades because of its ability to shave peaks.
The company was looking for various options for battery storage, including 20 minutes, 40 minutes and 60 minutes. The idea is to reduce spinning reserve from the gas plant from 8MW to 3MW, but the storage will also be required to provide frequency support, for “solar smoothing” and to “load shift” the solar.
“It is anticipated that the peak shaving duty will require a discharge of approximately 1 MW for 2 to 4 hours,” the document says,