A step closer to electrical self sufficiency
Saturday, 12th June, 2021
By Neil Pigot
Broken Hill came a step closer to being electrically self-sufficient this week with overwhelmingly favourable results delivered by a third-party economic impact report for a proposed 200 MW Advanced Compressed Air Energy Storage system developed by European green energy company Hydrostor and Australian sustainable energy developer Energy Estate.
In 2020, Hydrostor’s 200 MW, 8 hour or 1600 MWh storage system was selected by NSW’s transmission network service provider, Transgrid, as the preferred option for a reliable and secure electricity storage supply for Broken Hill in response to Essential Energy’s decision to decommission diesel back up generation for the city.
The ecologically sensitive system uses off-peak or surplus electricity from the grid or other renewable source to run compressors that produce heated compressed air. Heat is extracted from the air stream and stored inside a purpose-built cavern where hydrostatic compensation is used to maintain the system at a constant pressure, preserving the heat energy for use later in the cycle.
Hydrostatic pressure then forces the air to the surface where it is recombined with the stored heat and expanded through a turbine to generate electricity on demand, offering the same service as a natural gas plant while having zero emissions.
The impact report demonstrated significant economic benefits to the local community with total investment expected to be up to $560 million, with the vast majority of construction expenditures occurring within the community of Broken Hill.
The Project will employ an average of 260 full time equivalent construction jobs over three years, with a peak in the second year of construction reaching 350. On completion it is expected to support substantial local employment opportunities with 70 ongoing jobs through the course of the facility’s operational life of 50 years.
In addition to the economic benefits, the project will provide a critical long-term grid reliability solution to the city in a manner that does not rely on fossil fuels, eliminating potential supply chain disruptions. Importantly the project is also up-scalable, enabling the community and future mining operations to grow over time.
In announcing the positive economic feasibility study Simon Currie, Principal of Energy Estate echoed the recent words of Cobalt Blue CEO Joe Kaderavek and demonstration plant manager Adam Randall in outlining Energy Estate and Hydrostar’s commitment to ethical development.
“We will be, as are Cobalt Blue, committed to hiring and upskilling a local workforce wherever possible to build and operate the facility. We want this to be a community driven project with the best interests of the community at its centre. It’s a world leading technology that will provide class leading jobs in what is clearly a part of our global energy future.”
Hydrostor’s innovative technology is perfectly suited to a location like Broken Hill because it can utilise existing mine infrastructure to create the storage cavern. And the availability of a large renewable energy source only adds to the overall “symmetry” of the project.
“We can build a green field cavern in any location but of course the cost will be higher. Having an existing site makes the project even more appealing,” Mr Currie said.
Informal conversations between Energy Estate and Cobalt Blue have led to agreement as to ways in which the project can be mutually beneficial, with any additional step toward environmentally sustainable energy production only adding to the international attractiveness of truly “green” cobalt from Cobalt Blue’s Broken Hill mine.
“I was speaking with Joe and he can see a fleet of electric buses tacking workers out to their site. It’s an exciting idea.”
Energy Estate are in negotiations for a mine site and expect to announce the location in the coming weeks. All things going well, Currie expects the facility to be online by 2025.