en.Wedoany.com Reported - The Wooreen Battery Energy Storage System in the Latrobe Valley, Victoria, Australia, has reached a construction milestone: all 1,038 Wärtsilä Quantum battery units have been delivered and installed. Zenviron, the balance-of-plant contractor, confirmed this milestone on LinkedIn, calling the delivery of the 1,038th and final unit an "outstanding achievement for the entire team." The project will now transition to remaining commissioning and grid connection work, with owner EnergyAustralia and equipment supplier Wärtsilä targeting commercial operations in 2027.
The Wooreen BESS has an installed capacity of 350MW and an energy storage capacity of 1,474MWh, with a discharge duration of 4 hours. The project is being built adjacent to EnergyAustralia's Jeeralang power station and is planned to enter service before the closure of the Yallourn coal-fired power station (expected to retire in mid-2028). Finnish marine and energy technology group Wärtsilä signed the project contract in the fourth quarter of 2024, publicly disclosed in February 2025, with a scope of services including engineering design, equipment supply, commissioning, and a 15-year operations and maintenance agreement. The system utilizes Wärtsilä's Quantum High Energy hardware and the GEMS digital energy platform, designed to operate in grid-forming mode, providing synthetic inertia and faster response times to ensure grid stability as Victoria's power system phases out coal-fired generation.
When Wärtsilä launched the Quantum High Energy product in late 2023, it noted that the product uses 306Ah lithium-ion cells, offering a 9% increase in energy density over the previous generation, while enhancing fire protection measures—including active dehumidification, prefabricated firewalls between units, and a dual sprinkler system. The higher energy density directly reduces the number of units required per plant, lowering the footprint and logistical complexity of large-scale projects like Wooreen; all 1,038 individual units have been received and installed in phases. In July 2025, EnergyAustralia sold a 50% stake in the 1,400MWh Wooreen BESS to Thai energy company Banpu Public Company for approximately A$700 million (US$490 million), with Banpu also providing A$110 million in equity injection.
Since breaking ground in February 2025, the Wooreen project has adopted a multi-contractor parallel construction model. EnergyAustralia commenced construction within days of reaching financial close, with Victoria's Minister for Energy, Lily D'Ambrosio, attending the groundbreaking ceremony. Zenviron, a joint venture between engineering group Monadelphous and renewable energy developer ZEM Energy, secured the balance-of-plant contract, covering design, construction, installation, and commissioning. The project received support from the first round of the Australian government's Capacity Investment Scheme (CIS), a key federal mechanism to underwrite investment in new energy storage within the National Electricity Market (NEM). EnergyAustralia also has the Hallett BESS (50MW/250MWh) project in South Australia, which reached financial close in February 2026, using NHOA Energy as the battery integrator, targeting mid-2027 operations. With battery installation complete, the Wooreen project enters the commissioning phase—units will be progressively energized, tested, and integrated into the site control system, followed by establishing the grid connection. For a project with 1,038 units, commissioning is typically carried out in sequential blocks rather than all at once, meaning some capacity may become available before the Australian Energy Market Operator (AEMO) confirms the full 350MW rated capacity.
