Two pumped hydro projects including one which will be the world’s biggest have emerged as a critical part of Queensland’s plan to transition its energy network to clean energy sources.

The Queensland Government has unveiled its $62 billion Queensland Energy and Jobs Plan, which aims to transition the state’s energy system to a cleaner future.

Part of the plan involves the investigation into the feasibility of two pumped-hydro projects: the Borumba pumped hydro project located near Imbil and the Pioneeer-Burdekin pumped hydro project in the Pioneer Valley near Mackay.

Of these, the 5GW Pioneer-Burdekin project has the potential to be the world’s largest pumped hydro energy scheme and to supply around half of Queensland’s energy.

Its generation capacity would be around 2.5 times that of Snowy Hydro 2.0.

A critical technology in enabling electricity systems to transition to clean energy, pumped hydro acts like a giant energy battery.

Each pumped hydro scheme has two reservoirs: one at a higher elevation and the other at a lower elevation.

When energy supplies are plentiful and prices are low (usually during the day), water is pumped uphill from the lower reservoir to the higher one using electricity which is sourced either from the grid or nearby renewables.

When more energy is needed (often at night), water is released from the upper reservoir back down to the lower one – a process which generates electricity as the water passes through a turbine on its way down.

As this process results in almost immediate electricity generation, it can be used to feed power into the grid when needed.

“It’s like a giant battery,” Queensland Deputy Premier Steven Miles said.

“We will use cheap solar electricity during the day to pump water up the mountain to store it.

“Then at night we can release the water to generate electricity.”

As things stand, pumped hydro provides 96 percent of energy storage capacity worldwide.

Whilst batteries (the other main storage technology) are falling in price, they are currently unable to compete with the low cost of pumped hydro for large-scale energy storage.

Australia currently has three existing pumped hydro storage systems: the Wivenhoe System in Queensland, the Shoalhaven Scheme in New South Wales, and the Tumut 3 System also in New South Wales.

There are two more systems currently under construction: Snow 2.0 in New South Wales and Kidston in Queensland. A dozen more are under serious consideration across both Queensland and NSW.

In its announcement, the Government said it has set aside $273.5 million to advance investigations for the two projects. This includes $203.5 million in new money.

Funding will support detailed engineering and environmental investigation, community engagement and some early access work.

The Government will also establish a new agency known as Queensland Hydro to drive delivery of the assets.

As things stand, the proposed Pioneer-Burdekin project remains in the initial study phase.

Analytical studies and community consultation are set to take place during 2024-26.

The smaller Borumba project has been undergoing detailed design and cost analysis along with community consultation.

Next year, the government hopes to progress assessment and conduct some early works.

Should all go to plan, both schemes are expected to be operational by 2035.

The two pumped hydro schemes are part of a 23-point plan which the government says will help to build a clean energy economy, deliver a greater range of options and more affordable power for households and businesses and secure jobs and communities.

As part of the plan, the government hopes to have renewables supply up to 70 percent of the state’s energy from 2032 and 80 percent from 2035. It also hopes to reduce energy related greenhouse gas emissions by 90 percent from that date.

Solar, wind, pumped hydro and battery assets will be linked statewide via a new super grid.

Publicly owned coal-fired power stations will cease to rely on burning coal by 2035 and will convert to clean energy hubs producing electricity from sources such as hydropower.

All up, the plan is expected to generate around 100,000 new jobs – many of which will be in regional areas.

The latest announcement comes as energy sector experts caution that Australia’s transition to a netzero electricity grid must be carefully planned.

During a recent panel discussion hosted by the Academy of Technology and Engineering, panelists said the transition to netzero energy will require a portfolio of technologies, a strong regulatory framework to encourage investment, more energy storage capacity, effective grid management and effective management of energy demand.

Queensland Premier Anastacia Palaszczuk says the plan will help to set Queensland up for the next century.

“This plan is all about cheaper, cleaner and secure energy for Queenslanders,” she said.

“It is about turbo-charging new investment in new minerals, batteries and manufacturing.

“Renewable energy is the cheapest form of new energy (according to the Australian Energy Market Operator).

“This plan makes Queensland the renewable energy capital of the world.”