Plans to build a $1.6 billion battery in Collie look set to be given a green light by the Regional Joint Development Assessment Panel on Friday, after the project was recommended for approval. Synergy’s huge proposal will be key in the energy transition as the State Government pursues a bid to shut down nearby public coal power stations by 2030. The battery will store up to 2000 megawatt-hours of electricity, roughly equivalent to six hours of production at the neighbouring Collie Power Station. The documents show a further expansion to double the size of the battery are also under consideration. Work on stage one will start in 2024 and construction will take about two years, with 800 workers on-site at the peak. In September, Synergy awarded contracts to China’s CATL and Power Electronics for the Collie project and the second stage of the Kwinana Big Battery. The value of firming capacity was thrown into sharp relief in recent months with demand on the grid hitting its lowest level ever in September. InfrastructureWA has also ticked off the battery projects but not before critiquing the business case Synergy used for its investment decision. It was only after extensive probing that the umpire was given clarification on key details about the impact of coal closures on the grid, Synergy’s ability to deliver, and the level of options assessment undertaken before the utility approved the plans. The government utility was also warned to “establish robust investment logic mapping practices to inform future business cases to ensure that all problems that a proposal is attempting to address are clearly outlined in proposal documentation”. The IWA report shows Synergy hopes the storage projects will also help improve its troubled finances with an 11-year payback forecast.