Zinc mine given new, renewable life


In an Australian first, an abandoned zinc mine will be repurposed into the nation’s first compressed air facility for renewable energy storage.

The Angas Zinc Mine in Strathalbyn, 60 kilometres southeast of Adelaide, will be repurposed to house the 5 MW / 10 MWh fuel-free Advanced Compressed Air Energy Storage (A-CAES) facility.

With $6 million from the Australian Renewable Energy Agency (ARENA), the $30 million private-public partnership will see the Hydrostor Australia construct the facility that will use synchronous inertia, load shifting, frequency regulation and support for grid security and reliability.

The technology works by using electricity from the grid to produce compressed air, which is stored in a purpose-built underground cavern kept at constant pressure using hydrostatic head from a water column.

During charging, heat from the compressed air is collected and stored before the cooled air displaces water out of the cavern up to a water reservoir on the surface. To discharge, water flows back into the cavern forcing air to the surface under pressure where it is heated with the stored thermal energy and drives a turbine to generate electricity.