Big-T scheme moves forward in Queensland

Bechtel, USA, has been assigned Early Contractor Involvement (ECI) by BE Power and GE Renewable Energy for the 400 MW/440 MW Big-T pumped-storage project in the state of Queensland, Australia.

The company will assist the project partners with optimizing the design and planning for the project, at Lake Cressbrook in southeast Queensland, and take on the role of EPC contractor should the project proceed to construction. Bechtel announced on 4 August it would provide support to the project development under a service agreement that would include: advancing the design; facilitating early contractor cost savings and constructability; advising how to best structure core contracts; and, starting supply chain engagement with a view to maximizing local content and indigenous participation. The project partners are currently completing a bankable feasibility study with a final investment decision scheduled for the fourth quarter of next year. If achieved, Bechtel would engineer, procure, and construct the project. Commercial operation is targeted for the first quarter of 2027. The 400 MW ‘turkey’s nest’ style pumped-storage facility is being jointly developed by BE Power and GE Renewable Energy under an agreement signed in December 2020 at a funded cost of A$ 1.2 billion. It will use an existing reservoir impounded by the Cress­brook dam near Too­woomba as the lower reservoir. A new upper reservoir is to be constructed nearby. The developers recently expanded the project scope to include a battery energy storage system (BESS) with notional capacity of 200 MWh. The inclusion of the BESS will provide a ‘world first’ combination of short duration storage technology with medium-to-long duration storage technology, and will enable the project to deliver all future system requirements of grid response, network frequency (grid stability), inertia, renewable firming, and energy at duration. Engineering and feasibility of this component of the project is being assessed. On completion of these studies, the BESS is planned to be developed on a separate development pathway from Big-T. The Big-T project is designed to support Australia’s transition away from its aging baseload coal-fired generation capacity, enabling more asynchronous renewable power generation (prin­cipally solar and wind) within the Queensland Government’s southern Renewable Energy Zone (REZ). This will contribute to the state’s target of 50 per cent renewable energy generation by 2030. The southern REZ is one of three REZs announced by the State Government in 2020. Big-T would generate 400 MW with 10 hours of storage, implying around 4000 MWh of storage capacity, and is expected to deliver significant cost savings, as well as improve the reliability of supply to consumers. The project will also bring significant social and economic benefits to the Toowoomba and Somerset regions of Queensland, according to the developers. This in­cludes local investment and employment opportunities, for ex­am­ple around 250-500 jobs during construction and 15-30 jobs during operation. Big T is a shortlisted project for the Australian Federal Government’s Underwriting New Generation In­vestment (UNGI) programme. This was established to support firm generation capacity and increase competition as part of the Australian Gov­ernment’s commitment to lowering electricity prices and increasing grid reliability. Along with supporting and investing in large-scale batteries, the Government of Queens­land recently also contributed A$ 48 million (US$ 33.37 million) funding towards feasibility studies for two pumped-storage projects.