Powerlink has been chosen by the state government to conduct a detailed cost and design analysis, including engineering and design, hydrological modelling and geological testing. These studies will begin in the second half of this year and will take around 24 months to complete, with final outcomes expected before the end of 2023. An assessment of environmental impacts will be undertaken as part of the analysis, and the Queensland Government said it would work with First Nations and conservation groups as well as the broader community to ensure appropriate protection of national parks and biodiversity. Residents and community groups will also have the opportunity to provide feedback and input into what could also become a larger recreational and tourism hub. The project, at Borumba dam in the Wide Bay – Burnett region, about 70 km southwest of Noosa, would be capable of generating up to 1 GW at maximum capacity, which would be able to supply more than 15 per cent of Queensland’s average electricity demand.
The project would store enough water to deliver this output for 24 hours continuously, which would make Borumba one of the largest such facilities in the world in terms of storage capacity. Creation of a pumped-storage plant at Borumba will require a new dam to be built above the existing one, with a storage capacity of 31.5 x 106m3, and expansion of the existing lower reservoir. A 2.6 km-long tunnel would also need to be built to connect the two reservoirs. Borumba dam is a 43 m-high rockfill embankment structure, which was commissioned in 1964. Borumba was selected as the first site for detailed cost and design analysis, following a state-wide assessment of potential pumped-storage locations. The site is favoured because of its proximity to the high-voltage transmission network, existing dam infrastructure, and location within the Southern Queensland Renewable Energy Zone. The Queensland Government had previously identified the site as a possible location for pumped storage, and Powerlink has held the site since the 1980s. However, a fire at the 1720 MW Callide coal-fired power station and subsequent blackout in May this year has given the project a new urgency. Minister for Energy, Renewables and Hydrogen, Mick de Brenni said that the crisis “proved” the importance of having pumped storage as part of a diversified energy mix. “We were able to ramp up the Wivenhoe hydro station to provide critical generation support and stabilise the network,” de Brenni said. Borumba would have doubled the generation and tripled the storage of Wivenhoe, he added. The Australian Energy Market Operator has identified that Queensland will need significant energy storage as part of a diverse future energy system and as the state progresses to 50 per cent renewables by 2030.