The K2-Solar project forms a key part of the plan to build a pumped hydro storage project in the old Kidston gold mine.

Engineering contracts for both components are expected to be completed by the end of June, and discussions on finance are also taking place.

It has also selected hydraulic power specialist Andritz as the preferred electromechanical equipment supplier, including the reversible Francis pump-turbines.

It published this 3D image above, showing the internal structure between the two reservoirs showing the axis spiral decline, intake shaft (far right), cable shaft (middle) and emergency egress (left) and the tailrace tunnel at the bottom.

Genex indicated that it was likely to build the K2-Solar project in stages to match energy off take agreement and “energy transfer capabilities”.

The Kidston project may be the first, but will not be the only large scale solar plant to be paired with pumped hydro storage.

SIMEC ZEN Energy is also looking at solar and storage as part of plans to power the Whyalla steel works with renewable energy, and to install more than 1GW of solar in South Australia to power other big manufacturing businesses too.