Boosting Australia’s renewable energy capacity by 750MW

Used in various forms across the globe, hydropower is one of the most mature energy technologies. In Australia, pumped hydro energy storage (PHES) is a crucial technology driving the energy transition. It offers a proven and reliable solution for storing excess energy and delivering power on demand.

With up to 22,000 potential sites identified by the Australian Renewable Energy Agency, capable of storing 67,000 GWh of energy, Australia’s potential to become a global leader in PHES is evident.

One of those sites is the Capricornia Pumped Hydro project, located on Widi Country, approximately 80km west of Mackay in Queensland. Capricornia will generate 750MW, with a storage capacity of 12GWh, or around 16 hours, and is expected to be operational by 2032.

A trusted partner

A unique blend of skills and experience positioned us as the leading technical team, capable of delivering high-quality designs and effective solutions for the Capricornia project.

Following a pre-feasibility study completed in January 2024, we were appointed to deliver a detailed feasibility study which involved a concept assessment to confirm the best option and ensure the right design inputs. We’re now completing the reference design for the early contractor involvement (ECI) phase - a crucial step as the basis for contractor tenders for the design and construction (D&C) contract - with the aim of accelerating the project towards financial close and construction.

The team’s deep technical knowledge and commercial acumen gained from working on some of Australia’s largest PHES developments, including Kidston and Musswellbrook, has enabled us to navigate complex decisions and provide valuable recommendations throughout each stage of the project.

The most rewarding part of working on Capricornia has been the mutual respect and trust that we have built with the client. This has allowed for open and productive discussions, meaning we’re able to add value by being part of the decision-making and acting together as a single unit.

Paul Currie

Energy leader, Asia Pacific, Australia and New Zealand

This ability to work collaboratively with the client and add significant value through maintaining close relationships has been a particularly rewarding aspect for Paul Currie, project director and energy leader for Asia Pacific, New Zealand and Australia.

Cost-effective solutions through informed decision-making

The energy transition requires a substantial increase of capital expenditure on renewable energy projects. This comes with a relatively high upfront investment with lower operating and fuel expenditures over time. At the end of the day, cost is front-of-mind for developers looking to invest in renewables.

Because of our strong industry relationships and understanding of contractor preferences and project requirements, we’ve been able to make informed recommendations on design decisions that aim to reduce overall project costs for our client.

For example, during the pre-feasibility study, we had to decide between having three tunnels or one tunnel for the design of the waterways. The decision was challenging due to the contractor not being involved at that stage of the project. We used knowledge of contractor preferences and construction methodologies gained on previous projects in Australia to recommend one tunnel, anticipating it would be more favourable for the program. One tunnel would lead to efficiencies in the construction process, potentially avoiding higher costs associated with more complex construction methods. This recommendation was later validated by the contractor, confirming our innate understanding of PHES projects.

Pumped storage is key to ensuring grid stability in Australia

The Capricornia PHES facility will provide large-scale dispatchable power to Queensland. With the Queensland coal-fired power stations commencing decommissioning from 2028, long-duration energy storage combined with grid strength and stability services will be key to maintaining grid stability and keeping electricity prices low. Projects like Capricornia will mean consistent and cost-effective supply of electricity for homes, businesses and essential services across Australia.