Battery storageProject Lake Bonney Battery Energy Storage System
This report summarises the operations of the Lake Bonney Battery Energy Storage System in its first seven months of operation, from December 2019 to June 2020.
Records for energy demand in South Australia were set for both minimum and maximum operating levels during the reporting period. However, average energy prices during summer were not adversely impacted by high operational demand. Contingency FCAS requirements in the NEM were increased over the reporting period as AEMO updated its load relief assumptions.
Two major separation events occurred in the South Australian region of the NEM in the reporting period. The larger of these, the 31st January separation event, saw South Australia operate as an island for over two weeks. During this time, all FCAS prices greatly increased as AEMO could only source these services from participants within the SA region.
Charging and discharging behaviour
The Lake Bonney BESS (as a generator) had an equivalent capacity factor, in energy only, of 1.64% during the reporting period and this contributed to 27% of the total discharge energy, highlighting that the BESS’ operation is not limited to the energy market.
Energy arbitrage opportunities were variable between months, but the majority of potential energy revenue was concentrated on isolated high-priced events. While the participation of the BESS during high-price events was hindered in some instances due to constraints imposed in islanded conditions, the decisions made by a human operator with experience of the SA market dynamics allowed for the BESS to discharge throughout a high-price event.