“Snapping back like a chihuahua:” Dark skies over air battery as outback tourism business goes to court

Plans to build a world-first renewable energy mini-grid in Broken Hill based on groundbreaking compressed air energy storage have hit a new hurdle, in the form of a legal challenge launched by a tourism business that depends on dark skies.

The 200 megawatt (MW), up to eight hour (1600 MWh) duration Silver City Energy Storage project by Canadian compressed air technology company Hydrostor won New South Wales development approval in late February.

But an ABC News report on Thursday says the owners of local tourism business Outback Astronomy have lodged an appeal in the Land and Environment Court challenging the government’s decision to approve the project.

According the the ABC, the appeal claims Silver City – which is being developed at the site of an existing silver mine – will adversely impact Outback Astronomy’s business operations, including through the impact of light and noise pollution and disturbances associated with construction.

The owners of Outback Astronomy, Linda and Travis Nadge, published a blog post on the company website in January claiming that they have been “suffering for three years” over concerns about the energy storage project’s potential impacts.

“Now, we are snapping back like a chihuahua in a crowded supermarket,” the blog post says.

Renew Economy has not seen the court documents, but in a detailed nine-page submission to the NSW government, dated February 09, 2025, Outback Astronomy says “we object to this project because it will ruin our tourism business and our environmental lifestyle, located at 1.13km from its surface plant.”

The submission also claims that the Hydrostor project will be “energy intensive and will represent an additional load on the electricity grid,” will “result in additional net greenhouse gas (GHG) emissions” and that Hydrostor has “engaged a registered lobbyist to frame language around the project.”

The January company blog post links to a secondary website – https://outbackastronomy.xyz/ – which the Nadges say they have set up in an “effort to correct some of the project spin.” A message on that website says “publication of information temporarily on hold pending an appeal with the NSW Land and Environment Court.”

Canada-based Hydrostor describes its Advanced Compressed Air Energy Storage (A-CAES) as similar to pumped hydro, delivering long duration storage by using a proprietary thermal management system and the use of purpose-built hard-rock air-storage caverns.

Essentially, the technology uses renewable energy to compress air and store it underground. When electricity is needed, the air is released through a turbine. For the Broken Hill project, the compressed air will be housed in a cavern inside Perilya’s Potosi silver mine.

Silver City was selected back in 2020 by network company Transgrid as the best option to replace two ageing 25MW diesel-fuel fired generators currently used to provide back-up electricity supply for Broken Hill, which is located at the end of a long (260km) single line and prone to outages.

Gas options, including installing new turbines, were considered, as was a new transmission line, but quickly dismissed due to cost and lack of market benefits.

The costs of the individual storage proposals were not revealed – commercial in confidence – but Transgrid said at the time that the market benefits were far superior, with the compress air proposal leading the way.

Since then – give or take a tangle with archaic energy market regulations – the Silver City Energy Storage Centre has won council support, has been awarded federal government funding through Arena, has been waved through the EPBC queue, has been awarded a Long-Term Energy Service Agreement (LTESA) by AEMO Services as part of the NSW Electricity Infrastructure Roadmap, and has won state state development approval.

For its part, Hydrostor says it is keen to be respectful to all stakeholders and to let the legal process run its course. In an emailed statement to Renew Economy, the company’s senior vice president of origination and development, Martin Becker, said:

“Community engagement has been a crucial part of the development process for the Silver City Energy Storage Centre, and Hydrostor has been pleased with the strong community support for the project throughout Broken Hill.

“Hydrostor supports and is committed to working through the process offered through the Land and Environment Court, and we’re confident there is a path for the project and all local stakeholders to co-exist.”